1
|
McCaw BA, Leonard AM, Stevenson TJ, Lancaster LT. A role of epigenetic mechanisms in regulating female reproductive responses to temperature in a pest beetle. INSECT MOLECULAR BIOLOGY 2024; 33:516-533. [PMID: 38864655 DOI: 10.1111/imb.12933] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Accepted: 05/23/2024] [Indexed: 06/13/2024]
Abstract
Many species are threatened by climate change and must rapidly respond to survive in changing environments. Epigenetic modifications, such as DNA methylation, can facilitate plastic responses by regulating gene expression in response to environmental cues. Understanding epigenetic responses is therefore essential for predicting species' ability to rapidly adapt in the context of global environmental change. Here, we investigated the functional significance of different methylation-associated cellular processes on temperature-dependent life history in seed beetles, Callosobruchus maculatus Fabricius 1775 (Coleoptera: Bruchidae). We assessed changes under thermal stress in (1) DNA methyltransferase (Dnmt1 and Dnmt2) expression levels, (2) genome-wide methylation and (3) reproductive performance, with (2) and (3) following treatment with 3-aminobenzamide (3AB) and zebularine (Zeb) over two generations. These drugs are well-documented to alter DNA methylation across the tree of life. We found that Dnmt1 and Dnmt2 were expressed throughout the body in males and females, but were highly expressed in females compared with males and exhibited temperature dependence. However, whole-genome methylation did not significantly vary with temperature, and only marginally or inconclusively with drug treatment. Both 3AB and Zeb led to profound temperature-dependent shifts in female reproductive life history trade-off allocation, often increasing fitness compared with control beetles. Mismatch between magnitude of treatment effects on DNA methylation versus life history effects suggest potential of 3AB and Zeb to alter reproductive trade-offs via changes in DNA repair and recycling processes, rather than or in addition to (subtle) changes in DNA methylation. Together, our results suggest that epigenetic mechanisms relating to Dnmt expression, DNA repair and recycling pathways, and possibly DNA methylation, are strongly implicated in modulating insect life history trade-offs in response to temperature change.
Collapse
Affiliation(s)
- Beth A McCaw
- School of Biological Sciences, University of Aberdeen, Aberdeen, Scotland
| | - Aoife M Leonard
- Centre for Evolutionary Hologenomics, GLOBE Institute, University of Copenhagen, Copenhagen, Denmark
| | - Tyler J Stevenson
- School of Biological Sciences, University of Aberdeen, Aberdeen, Scotland
| | - Lesley T Lancaster
- School of Biological Sciences, University of Aberdeen, Aberdeen, Scotland
| |
Collapse
|
2
|
Zheng C, Shi H, Wei J, Cui M, Lin Z, Gao Y, Yuan L, Wen Z. Evidence that spatial scale and environment factors explain grassland community assembly in woodland-grassland ecotones. Ecol Evol 2024; 14:e11644. [PMID: 38962022 PMCID: PMC11221066 DOI: 10.1002/ece3.11644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Revised: 06/07/2024] [Accepted: 06/12/2024] [Indexed: 07/05/2024] Open
Abstract
How communities of living organisms assemble has long been a central question in ecology. The impact of habitat filtering and limiting similarity on plant community structures is well known, as both processes are influenced by individual responses to environmental fluctuations. Yet, the precise identifications and quantifications of the potential abiotic and biotic factors that shape community structures at a fine scale remains a challenge. Here, we applied null model approaches to assess the importance of habitat filtering and limiting similarity at two spatial scales. We used 63 natural vegetation plots, each measuring 5 × 5 m, with three nested subplots measuring 1 × 1 m, from the 2021 field survey, to examine the alpha diversity as well as beta diversity of plots and subplots. Linear mixed-effects models were employed to determine the impact of environmental variables on assembly rules. Our results demonstrate that habitat filtering is the dominant assembly rules at both the plot and subplot levels, although limiting similarity assumes stronger at the subplot level. Plot-level limiting similarity exhibited a positive association with fine-scale partitioning, suggesting that trait divergence originated from a combination of limiting similarity and spatial partitioning. Our findings also reveal that the community assembly varies more strongly with the mean annual temperature gradient than the mean annual precipitation. This investigation provides a pertinent illustration of non-random assembly rules from spatial scale and environmental factors in plant communities in the loess hilly region. It underscores the critical influence of spatial and environmental constraints in understanding the assembly of plant communities.
Collapse
Affiliation(s)
- Cheng Zheng
- College of Grassland AgricultureNorthwest A&F UniversityYanglingShaanxiPeople's Republic of China
| | - Haijing Shi
- Institute of Soil and Water ConservationChinese Academy of Sciences and Ministry of Water ResourcesYanglingShaanxiPeople's Republic of China
- Institute of Soil and Water ConservationNorthwest A&F UniversityYanglingShaanxiPeople's Republic of China
| | - Jiaqi Wei
- College of Grassland AgricultureNorthwest A&F UniversityYanglingShaanxiPeople's Republic of China
| | - Mengying Cui
- College of Grassland AgricultureNorthwest A&F UniversityYanglingShaanxiPeople's Republic of China
| | - Ziqi Lin
- College of Grassland AgricultureNorthwest A&F UniversityYanglingShaanxiPeople's Republic of China
| | - Yuan Gao
- Institute of Soil and Water ConservationChinese Academy of Sciences and Ministry of Water ResourcesYanglingShaanxiPeople's Republic of China
| | - Liuhuan Yuan
- College of Grassland AgricultureNorthwest A&F UniversityYanglingShaanxiPeople's Republic of China
| | - Zhongming Wen
- College of Grassland AgricultureNorthwest A&F UniversityYanglingShaanxiPeople's Republic of China
- Institute of Soil and Water ConservationChinese Academy of Sciences and Ministry of Water ResourcesYanglingShaanxiPeople's Republic of China
| |
Collapse
|
3
|
Earley AM, Nolting KM, Donovan LA, Burke JM. Trait variation and performance across varying levels of drought stress in cultivated sunflower ( Helianthus annuus L.). AOB PLANTS 2024; 16:plae031. [PMID: 39011498 PMCID: PMC11247526 DOI: 10.1093/aobpla/plae031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Accepted: 05/24/2024] [Indexed: 07/17/2024]
Abstract
Drought is a major agricultural challenge that is expected to worsen with climate change. A better understanding of drought responses has the potential to inform efforts to breed more tolerant plants. We assessed leaf trait variation and covariation in cultivated sunflower (Helianthus annuus L.) in response to water limitation. Plants were grown under four levels of water availability and assessed for environmentally induced plasticity in leaf stomatal and vein traits as well as biomass (performance indicator), mass fractions, leaf area, leaf mass per area, and chlorophyll content. Overall, biomass declined in response to stress; these changes were accompanied by responses in leaf-level traits including decreased leaf area and stomatal size, and increased stomatal and vein density. The magnitude of trait responses increased with stress severity and relative plasticity of smaller-scale leaf anatomical traits was less than that of larger-scale traits related to construction and growth. Across treatments, where phenotypic plasticity was observed, stomatal density was negatively correlated with stomatal size and positively correlated with minor vein density, but the correlations did not hold up within treatments. Four leaf traits previously shown to reflect major axes of variation in a large sunflower diversity panel under well-watered conditions (i.e. stomatal density, stomatal pore length, vein density, and leaf mass per area) predicted a surprisingly large amount of the variation in biomass across treatments, but trait associations with biomass differed within treatments. Additionally, the importance of these traits in predicting variation in biomass is mediated, at least in part, through leaf size. Our results demonstrate the importance of leaf anatomical traits in mediating drought responses in sunflower, and highlight the role that phenotypic plasticity and multi-trait phenotypes can play in predicting productivity under complex abiotic stresses like drought.
Collapse
Affiliation(s)
- Ashley M Earley
- Department of Plant Biology, University of Georgia, Athens, GA 30602, USA
| | - Kristen M Nolting
- Department of Plant Biology, University of Georgia, Athens, GA 30602, USA
| | - Lisa A Donovan
- Department of Plant Biology, University of Georgia, Athens, GA 30602, USA
| | - John M Burke
- Department of Plant Biology, University of Georgia, Athens, GA 30602, USA
- The Plant Center, University of Georgia, Athens, GA 30602, USA
| |
Collapse
|
4
|
Paź‐Dyderska S, Jagodziński AM. Potential of reproductive traits in functional ecology: A quantitative comparison of variability in floral, fruit, and leaf traits. Ecol Evol 2024; 14:e11690. [PMID: 39026952 PMCID: PMC11255459 DOI: 10.1002/ece3.11690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2024] [Revised: 06/10/2024] [Accepted: 06/20/2024] [Indexed: 07/20/2024] Open
Abstract
Despite their claimed low intraspecific variability, plant reproductive traits are less frequently used in functional ecology. Here we focused on underrepresented plant organs, i.e. flowers and fruits, by comparing their traits with well-established leaf traits. We evaluated 16 functional traits (six floral, six fruit, and four leaf traits) in a randomly selected group of woody species under comparable environmental conditions. We aimed to assess interspecific and intraspecimen variability and explore the potential of the proposed flower and fruit traits for ecological research. Traits related to the dry mass of flowers and fruits exhibited the highest interspecific variability, while carbon content traits in flowers and leaves had the lowest. At a specimen level, specific leaf area revealed the highest variation. Carbon content traits for all organs demonstrated the least intraspecimen variability, with flower carbon content being the least variable. Our study revealed connections between the newly proposed traits and widely recognized functional traits, uncovering intriguing links between the established traits and the floral and fruit traits upon which we focused. This complements the already well-recognized variability in plant form and function with additional insights into reproductive processes.
Collapse
Affiliation(s)
| | - Andrzej M. Jagodziński
- Institute of Dendrology, Polish Academy of SciencesKórnikPoland
- Poznań University of Life SciencesFaculty of Forestry and Wood Technology, Department of Game Management and Forest ProtectionPoznańPoland
| |
Collapse
|
5
|
Zhang N, Ma LX, Dong YW. Flight or fight: different strategies of intertidal periwinkle Littoraria sinensis coping with high temperature across populations. Integr Zool 2024. [PMID: 38897980 DOI: 10.1111/1749-4877.12857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/21/2024]
Abstract
Intertidal organisms usually live near their upper thermal limits, and are vulnerable to future global warming. As a vital response to thermal stress, thermoregulatory strategy in physiological and behavioral performance is essential for organisms coping with thermal stress and surviving the changing world. To investigate the relationship between the thermoregulatory strategy and habitat temperature, in the present study, we comparatively investigated the thermal responsive strategy among different geographic populations of the supralittoral snail Littoraria sinensis by determining snails' cardiac function and behavioral performance. Our results indicated that populations inhabiting high ambient temperatures had higher sublethal temperatures (i.e. Arrhenius breakpoint temperatures, ABTs, the temperature at which the heart rate shapely decreases with further heating) and lethal temperatures (i.e. Flatline temperatures, FLTs, the temperature at which heart rate ceases), and behaved less actively (e.g. shorter moving distances and shorter moving time) in the face of high and rising temperatures-a physiological fight strategy. On the other hand, populations at relatively low ambient temperatures had relatively lower physiological upper thermal limits with lower ABTs and FLTs and moved more actively in the face of high and rising temperatures-a behavioral flight strategy. These results demonstrate that the thermoregulatory strategies of the snails are closely related to their habitat temperatures and are different among populations surviving divergent thermal environments.
Collapse
Affiliation(s)
- Ning Zhang
- Key Laboratory of Mariculture, Ministry of Education, Fisheries College, Ocean University of China, Qingdao, China
| | - Lin-Xuan Ma
- Key Laboratory of Mariculture, Ministry of Education, Fisheries College, Ocean University of China, Qingdao, China
| | - Yun-Wei Dong
- Key Laboratory of Mariculture, Ministry of Education, Fisheries College, Ocean University of China, Qingdao, China
| |
Collapse
|
6
|
Minias P, Pap PL, Vincze O, Vágási CI. Correlated evolution of oxidative physiology and MHC-based immunosurveillance in birds. Proc Biol Sci 2024; 291:20240686. [PMID: 38889785 DOI: 10.1098/rspb.2024.0686] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Accepted: 05/06/2024] [Indexed: 06/20/2024] Open
Abstract
Maintenance and activation of the immune system incur costs, not only in terms of substrates and energy but also via collateral oxidative damage to host cells or tissues during immune response. So far, associations between immune function and oxidative damage have been primarily investigated at intra-specific scales. Here, we hypothesized that pathogen-driven selection should favour the evolution of effective immunosurveillance mechanisms (e.g. major histocompatibility complex, MHC) and antioxidant defences to mitigate oxidative damage resulting from immune function. Using phylogenetically informed comparative approaches, we provided evidence for the correlated evolution of host oxidative physiology and MHC-based immunosurveillance in birds. Species selected for more robust MHC-based immunosurveillance (higher gene copy numbers and allele diversity) showed stronger antioxidant defences, although selection for MHC diversity still showed a positive evolutionary association with oxidative damage to lipids. Our results indicate that historical pathogen-driven selection for highly duplicated and diverse MHC could have promoted the evolution of efficient antioxidant mechanisms, but these evolutionary solutions may be insufficient to keep oxidative stress at bounds. Although the precise nature of mechanistic links between the MHC and oxidative stress remains unclear, our study suggests that a general evolutionary investment in immune function may require co-adaptations at the level of host oxidative metabolism.
Collapse
Affiliation(s)
- Piotr Minias
- Department of Biodiversity Studies and Bioeducation, University of Lodz, Faculty of Biology and Environmental Protection, Banacha 1/3, 90-237 Lodz, Poland
| | - Péter L Pap
- Evolutionary Ecology Group, Hungarian Department of Biology and Ecology, Babeş-Bolyai University, Cluj-Napoca, Romania
| | - Orsolya Vincze
- Evolutionary Ecology Group, Hungarian Department of Biology and Ecology, Babeş-Bolyai University, Cluj-Napoca, Romania
- Wetland Ecology Research Group, HUN-REN Centre for Ecological Research, Institute of Aquatic Ecology, Debrecen, Hungary
- ImmunoConcEpT, University of Bordeaux, CNRS UMR 5164, Bordeaux, France
| | - Csongor I Vágási
- Evolutionary Ecology Group, Hungarian Department of Biology and Ecology, Babeş-Bolyai University, Cluj-Napoca, Romania
| |
Collapse
|
7
|
Durant PC, Bhasin A, Juenger TE, Heckman RW. Genetically correlated leaf tensile and morphological traits are driven by growing season length in a widespread perennial grass. AMERICAN JOURNAL OF BOTANY 2024; 111:e16349. [PMID: 38783552 DOI: 10.1002/ajb2.16349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Revised: 03/19/2024] [Accepted: 03/20/2024] [Indexed: 05/25/2024]
Abstract
PREMISE Leaf tensile resistance, a leaf's ability to withstand pulling forces, is an important determinant of plant ecological strategies. One potential driver of leaf tensile resistance is growing season length. When growing seasons are long, strong leaves, which often require more time and resources to construct than weak leaves, may be more advantageous than when growing seasons are short. Growing season length and other ecological conditions may also impact the morphological traits that underlie leaf tensile resistance. METHODS To understand variation in leaf tensile resistance, we measured size-dependent leaf strength and size-independent leaf toughness in diverse genotypes of the widespread perennial grass Panicum virgatum (switchgrass) in a common garden. We then used quantitative genetic approaches to estimate the heritability of leaf tensile resistance and whether there were genetic correlations between leaf tensile resistance and other morphological traits. RESULTS Leaf tensile resistance was positively associated with aboveground biomass (a proxy for fitness). Moreover, both measures of leaf tensile resistance exhibited high heritability and were positively genetically correlated with leaf lamina thickness and leaf mass per area (LMA). Leaf tensile resistance also increased with the growing season length in the habitat of origin, and this effect was mediated by both LMA and leaf thickness. CONCLUSIONS Differences in growing season length may promote selection for different leaf lifespans and may explain existing variation in leaf tensile resistance in P. virgatum. In addition, the high heritability of leaf tensile resistance suggests that P. virgatum will be able to respond to climate change as growing seasons lengthen.
Collapse
Affiliation(s)
- P Camilla Durant
- Department of Integrated Biology, University of Texas at Austin, Austin, 78712, TX, USA
| | - Amit Bhasin
- Department of Civil, Architectural and Environmental Engineering, University of Texas at Austin, Austin, 78712, TX, USA
| | - Thomas E Juenger
- Department of Integrated Biology, University of Texas at Austin, Austin, 78712, TX, USA
| | - Robert W Heckman
- Department of Integrated Biology, University of Texas at Austin, Austin, 78712, TX, USA
| |
Collapse
|
8
|
Stoehr AM, Glaenzer K, VanWanzeele D, Rumschlag S. Resource-based trade-offs and the adaptive significance of seasonal plasticity in butterfly wing melanism. Ecol Evol 2024; 14:e11309. [PMID: 38698928 PMCID: PMC11063730 DOI: 10.1002/ece3.11309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 02/25/2024] [Accepted: 04/07/2024] [Indexed: 05/05/2024] Open
Abstract
Phenotypic plasticity is the ability of an organism to alter its phenotype in response to environmental cues. This can be adaptive if the cues are reliable predictors of impending conditions and the alterations enhance the organism's ability to capitalize on those conditions. However, since traits do not exist in isolation but as part of larger interdependent systems of traits (phenotypic integration), trade-offs between correlated plastic traits can make phenotypic plasticity non- or maladaptive. We examine this problem in the seasonally plastic wing melanism of a pierid (Order Lepidoptera, Family Pieridae) butterfly, Pieris rapae L. Several wing pattern traits are more melanized in colder than in warmer seasons, resulting in effective thermoregulation through solar absorption. However, other wing pattern traits, the spots, are less melanized during colder seasons than in warmer seasons. Although spot plasticity may be adaptive, reduced melanism of these spots could also be explained by resource-based trade-offs. Theory predicts that traits involved in resource-based trade-offs will be positively correlated when variation among individuals in resource acquisition is greater than variation among individuals in resource allocation strategies, and negatively correlated when variation in allocation is greater than variation in acquisition. Using data from both field studies and laboratory studies that manipulate dietary tyrosine, a melanin precursor, we show that when allocation to thermoregulatory melanism (ventral hindwing, and basal dorsal fore- and hindwing "shading") varies substantially this trait is negatively correlated with spot melanism. However, when there is less variation in allocation to thermoregulatory melanism we find these traits to be positively correlated; these findings are consistent with the resource-based trade-off hypothesis, which may provide a non- or maladaptive hypothesis to explain spot plasticity. We also show that increased dietary tyrosine results in increased spot melanism under some conditions, supporting the more general idea that melanism may involve resource-based costs.
Collapse
Affiliation(s)
- Andrew M. Stoehr
- Department of Biological SciencesButler UniversityIndianapolisIndianaUSA
| | - Katelyn Glaenzer
- Department of Biological SciencesButler UniversityIndianapolisIndianaUSA
| | - Devin VanWanzeele
- Department of Biological SciencesButler UniversityIndianapolisIndianaUSA
| | | |
Collapse
|
9
|
Temme AA, Kerr KL, Nolting KM, Dittmar EL, Masalia RR, Bucksch AK, Burke JM, Donovan LA. The genomic basis of nitrogen utilization efficiency and trait plasticity to improve nutrient stress tolerance in cultivated sunflower. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:2527-2544. [PMID: 38270266 DOI: 10.1093/jxb/erae025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Accepted: 01/23/2024] [Indexed: 01/26/2024]
Abstract
Maintaining crop productivity is challenging as population growth, climate change, and increasing fertilizer costs necessitate expanding crop production to poorer lands whilst reducing inputs. Enhancing crops' nutrient use efficiency is thus an important goal, but requires a better understanding of related traits and their genetic basis. We investigated variation in low nutrient stress tolerance in a diverse panel of cultivated sunflower genotypes grown under high and low nutrient conditions, assessing relative growth rate (RGR) as performance. We assessed variation in traits related to nitrogen utilization efficiency (NUtE), mass allocation, and leaf elemental content. Across genotypes, nutrient limitation generally reduced RGR. Moreover, there was a negative correlation between vigor (RGR in control) and decline in RGR in response to stress. Given this trade-off, we focused on nutrient stress tolerance independent of vigor. This tolerance metric correlated with the change in NUtE, plasticity for a suite of morphological traits, and leaf element content. Genome-wide associations revealed regions associated with variation and plasticity in multiple traits, including two regions with seemingly additive effects on NUtE change. Our results demonstrate potential avenues for improving sunflower nutrient stress tolerance independent of vigor, and highlight specific traits and genomic regions that could play a role in enhancing tolerance.
Collapse
Affiliation(s)
- Andries A Temme
- Department of Plant Biology, University of Georgia, Athens, GA 30602, USA
- Department of Plant Breeding, Wageningen University & Research, 6700 HB Wageningen, The Netherlands
| | - Kelly L Kerr
- Department of Plant Biology, University of Georgia, Athens, GA 30602, USA
- School of Biological Sciences, University of Utah, Salt Lake City, UT 84112, USA
| | - Kristen M Nolting
- Department of Plant Biology, University of Georgia, Athens, GA 30602, USA
| | - Emily L Dittmar
- Department of Plant Biology, University of Georgia, Athens, GA 30602, USA
| | - Rishi R Masalia
- Department of Plant Biology, University of Georgia, Athens, GA 30602, USA
| | | | - John M Burke
- Department of Plant Biology, University of Georgia, Athens, GA 30602, USA
| | - Lisa A Donovan
- Department of Plant Biology, University of Georgia, Athens, GA 30602, USA
| |
Collapse
|
10
|
Taff CC, Baldan D, Mentesana L, Ouyang JQ, Vitousek MN, Hau M. Endocrine flexibility can facilitate or constrain the ability to cope with global change. Philos Trans R Soc Lond B Biol Sci 2024; 379:20220502. [PMID: 38310929 PMCID: PMC10838644 DOI: 10.1098/rstb.2022.0502] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2023] [Accepted: 11/21/2023] [Indexed: 02/06/2024] Open
Abstract
Global climate change has increased average environmental temperatures world-wide, simultaneously intensifying temperature variability and extremes. Growing numbers of studies have documented phenological, behavioural and morphological responses to climate change in wild populations. As systemic signals, hormones can contribute to orchestrating many of these phenotypic changes. Yet little is known about whether mechanisms like hormonal flexibility (reversible changes in hormone concentrations) facilitate or limit the ability of individuals, populations and species to cope with a changing climate. In this perspective, we discuss different mechanisms by which hormonal flexibility, primarily in glucocorticoids, could promote versus hinder evolutionary adaptation to changing temperature regimes. We focus on temperature because it is a key gradient influenced by climate change, it is easy to quantify, and its links to hormones are well established. We argue that reaction norm studies that connect individual responses to population-level and species-wide patterns will be critical for making progress in this field. We also develop a case study on urban heat islands, where several key questions regarding hormonal flexibility and adaptation to climate change can be addressed. Understanding the mechanisms that allow animals to cope when conditions become more challenging will help in predicting which populations are vulnerable to ongoing climate change. This article is part of the theme issue 'Endocrine responses to environmental variation: conceptual approaches and recent developments'.
Collapse
Affiliation(s)
- Conor C. Taff
- Laboratory Ornithology and Department of Ecology & Evolutionary Biology, Cornell University, Ithaca, NY 14853, USA
- Department of Biology, Colby College, Waterville, ME 04901, USA
| | - Davide Baldan
- Department of Biology, University of Nevada, Reno, NV 89557, USA
| | - Lucia Mentesana
- Evolutionary Physiology, Max Planck Institute for Biological Intelligence, 82319 Seewiesen, Germany
- Faculty of Sciences, Republic University, Montevideo, 11200, Uruguay
| | - Jenny Q. Ouyang
- Department of Biology, University of Nevada, Reno, NV 89557, USA
| | - Maren N. Vitousek
- Laboratory Ornithology and Department of Ecology & Evolutionary Biology, Cornell University, Ithaca, NY 14853, USA
| | - Michaela Hau
- Evolutionary Physiology, Max Planck Institute for Biological Intelligence, 82319 Seewiesen, Germany
- Department of Biology, University of Konstanz, Konstanz, 78467, Germany
| |
Collapse
|
11
|
Bass E. Getting to the root of divergent outcomes in the modulation of plant-soil feedbacks by benzoxazinoids. THE NEW PHYTOLOGIST 2024; 241:2316-2319. [PMID: 38263679 DOI: 10.1111/nph.19545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Accepted: 01/08/2024] [Indexed: 01/25/2024]
Abstract
This article is a Commentary on Gfeller et al. (2024), 241: 2575–2588.
Collapse
Affiliation(s)
- Ethan Bass
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY, 14853, USA
| |
Collapse
|
12
|
Roush AM, Zhang L, Hood GR, Ott JR, Egan SP. A test of trade-offs in dispersal and reproduction within and between a sister species pair of specialist insect herbivores. Oecologia 2024; 204:529-542. [PMID: 38324065 DOI: 10.1007/s00442-024-05512-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2023] [Accepted: 01/08/2024] [Indexed: 02/08/2024]
Abstract
Understanding the drivers of trade-offs among traits is vital for comprehending the evolution and maintenance of trait variation. Theoretical frameworks propose that evolutionary mechanisms governing trade-offs frequently exhibit a scale-dependent nature. However, empirical tests of whether trade-offs exhibited across various biological scales (i.e. individuals, populations, species, genera, etc.) remains scarce. In this study, we explore trade-off between dispersal and reproductive effort among sympatric sister species of wasps in the genus Belonocnema (Hymenoptera: Cynipini: Cynipidae) that form galls on live oaks: B. fossoria, which specializes on Quercus geminata, and B. treatae, which specializes on Q. virginiana. Specifically, our results suggest that B. fossoria has evolved reduced flight capability and smaller wings, but a larger abdomen and greater total reproductive effort than B. treatae, which has larger wings and is a stronger flier, but has a smaller abdomen and reduced total reproductive effort. These traits and the relationships among them remain unchanged when B. fossoria and B. treatae are transplanted and reared onto the alternative host plant, suggesting that trait divergence is genetically based as opposed to being a plastic response to the different rearing environments. However, when looking within species, we found no evidence of intraspecific trade-offs between wing length and reproductive traits within either B. fossoria or B. treatae. Overall, our results indicate that observed trade-offs in life history traits between the two gall former species are likely a result of independent adaptations in response to different environments as opposed to the amplified expression of within species intrinsic tradeoffs.
Collapse
Affiliation(s)
- Amy M Roush
- Department of BioSciences, Rice University, Houston, TX, 77005, USA
| | - Linyi Zhang
- Department of BioSciences, Rice University, Houston, TX, 77005, USA.
- Department of Biology, University of Toronto, Toronto, ON, M5S1A4, Canada.
- Department of Biological Sciences, George Washington University, Washington, DC, 20052, USA.
| | - Glen Ray Hood
- Department of Biological Sciences, Wayne State University, Detroit, MI, 48202, USA
| | - James R Ott
- Department of Biology, Population and Conservation Biology Program, Texas State University, San Marcos, TX, 78666, USA
| | - Scott P Egan
- Department of BioSciences, Rice University, Houston, TX, 77005, USA
| |
Collapse
|
13
|
Lee G, Sanderson BJ, Ellis TJ, Dilkes BP, McKay JK, Ågren J, Oakley CG. A large-effect fitness trade-off across environments is explained by a single mutation affecting cold acclimation. Proc Natl Acad Sci U S A 2024; 121:e2317461121. [PMID: 38289961 PMCID: PMC10861903 DOI: 10.1073/pnas.2317461121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Accepted: 12/26/2023] [Indexed: 02/01/2024] Open
Abstract
Identifying the genetic basis of local adaptation and fitness trade-offs across environments is a central goal of evolutionary biology. Cold acclimation is an adaptive plastic response for surviving seasonal freezing, and costs of acclimation may be a general mechanism for fitness trade-offs across environments in temperate zone species. Starting with locally adapted ecotypes of Arabidopsis thaliana from Italy and Sweden, we examined the fitness consequences of a naturally occurring functional polymorphism in CBF2. This gene encodes a transcription factor that is a major regulator of cold-acclimated freezing tolerance and resides within a locus responsible for a genetic trade-off for long-term mean fitness. We estimated the consequences of alternate genotypes of CBF2 on 5-y mean fitness and fitness components at the native field sites by comparing near-isogenic lines with alternate genotypes of CBF2 to their genetic background ecotypes. The effects of CBF2 were validated at the nucleotide level using gene-edited lines in the native genetic backgrounds grown in simulated parental environments. The foreign CBF2 genotype in the local genetic background reduced long-term mean fitness in Sweden by more than 10%, primarily via effects on survival. In Italy, fitness was reduced by more than 20%, primarily via effects on fecundity. At both sites, the effects were temporally variable and much stronger in some years. The gene-edited lines confirmed that CBF2 encodes the causal variant underlying this genetic trade-off. Additionally, we demonstrated a substantial fitness cost of cold acclimation, which has broad implications for potential maladaptive responses to climate change.
Collapse
Affiliation(s)
- Gwonjin Lee
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN47907
- Center for Plant Biology, Purdue University, West Lafayette, IN47907
| | - Brian J. Sanderson
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN47907
- Center for Plant Biology, Purdue University, West Lafayette, IN47907
| | - Thomas J. Ellis
- Plant Ecology and Evolution, Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, UppsalaSE-752 36, Sweden
| | - Brian P. Dilkes
- Center for Plant Biology, Purdue University, West Lafayette, IN47907
- Department of Biochemistry, Purdue University, West Lafayette, IN47907
| | - John K. McKay
- Department of Soil and Crop Sciences, Colorado State University, Fort Collins, CO80523
| | - Jon Ågren
- Plant Ecology and Evolution, Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, UppsalaSE-752 36, Sweden
| | - Christopher G. Oakley
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN47907
- Center for Plant Biology, Purdue University, West Lafayette, IN47907
| |
Collapse
|
14
|
Pearse IS, LoPresti E, Baldwin BG, Krimmel B. The evolution of glandularity as a defense against herbivores in the tarweed clade. AMERICAN JOURNAL OF BOTANY 2024; 111:e16281. [PMID: 38334065 DOI: 10.1002/ajb2.16281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Revised: 11/13/2023] [Accepted: 11/13/2023] [Indexed: 02/10/2024]
Abstract
PREMISE Glandular trichomes are implicated in direct and indirect defense of plants. However, the degree to which glandular and non-glandular trichomes have evolved as a consequence of herbivory remains unclear, because their heritability, their association with herbivore resistance, their trade-offs with one another, and their association with other functions are rarely quantified. METHODS We conducted a phylogenetic comparison of trichomes and herbivore resistance against the generalist caterpillar, Heliothis virescens, among tarweed species (Asteraceae: Madiinae) and a genetic correlation study comparing those same traits among maternal half-sibs of three tarweed species. RESULTS Within a tarweed species, we found no evidence that herbivore growth rate decreased on tarweed individuals or maternal sib groups with more glandularity or denser trichomes. However, tarweed species with more glandularity and fewer non-glandular trichomes resulted in slower-growing herbivores. Likewise, a trade-off between glandular and non-glandular trichomes was apparent among tarweed species, but not among individuals or sib groups within a species. CONCLUSIONS Our results suggest that this key herbivore does not select for trichomes as a direct defense in tarweed species. However, trichomes differed substantially among species and likely affect herbivore pressure on those species. Our results demonstrate that trade-offs among plant traits, as well as inference on the function of those traits, can depend on scale.
Collapse
Affiliation(s)
- Ian S Pearse
- U.S. Geological Survey, Fort Collins Science Center, Fort Collins, CO, USA
| | - Eric LoPresti
- Department of Biological Sciences, University of South Carolina, Columbia, SC, USA
| | - Bruce G Baldwin
- University of California-Berkeley, Jepson Herbarium and Department of Integrative Biology, Berkeley, CA, USA
| | | |
Collapse
|
15
|
Ravigné V, Rodrigues LR, Charlery de la Masselière M, Facon B, Kuczyński L, Radwan J, Skoracka A, Magalhães S. Understanding the joint evolution of dispersal and host specialisation using phytophagous arthropods as a model group. Biol Rev Camb Philos Soc 2024; 99:219-237. [PMID: 37724465 DOI: 10.1111/brv.13018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 09/11/2023] [Accepted: 09/11/2023] [Indexed: 09/20/2023]
Abstract
Theory generally predicts that host specialisation and dispersal should evolve jointly. Indeed, many models predict that specialists should be poor dispersers to avoid landing on unsuitable hosts while generalists will have high dispersal abilities. Phytophagous arthropods are an excellent group to test this prediction, given extensive variation in their host range and dispersal abilities. Here, we explore the degree to which the empirical literature on this group is in accordance with theoretical predictions. We first briefly outline the theoretical reasons to expect such a correlation. We then report empirical studies that measured both dispersal and the degree of specialisation in phytophagous arthropods. We find a correlation between dispersal and levels of specialisation in some studies, but with wide variation in this result. We then review theoretical attributes of species and environment that may blur this correlation, namely environmental grain, temporal heterogeneity, habitat selection, genetic architecture, and coevolution between plants and herbivores. We argue that theoretical models fail to account for important aspects, such as phenotypic plasticity and the impact of selective forces stemming from other biotic interactions, on both dispersal and specialisation. Next, we review empirical caveats in the study of this interplay. We find that studies use different measures of both dispersal and specialisation, hampering comparisons. Moreover, several studies do not provide independent measures of these two traits. Finally, variation in these traits may occur at scales that are not being considered. We conclude that this correlation is likely not to be expected from large-scale comparative analyses as it is highly context dependent and should not be considered in isolation from the factors that modulate it, such as environmental scale and heterogeneity, intrinsic traits or biotic interactions. A stronger crosstalk between theoretical and empirical studies is needed to understand better the prevalence and basis of the correlation between dispersal and specialisation.
Collapse
Affiliation(s)
- Virginie Ravigné
- CIRAD, UMR PHIM, - PHIM, University of Montpellier, CIRAD, INRAE, Institut Agro, IRD, TA A-120/K, Campus international de Baillarguet, avenue du Campus d'Agropolis, Montpellier Cedex 5, 34398, France
| | - Leonor R Rodrigues
- cE3c: Centre for Ecology, Evolution and Environmental Changes & CHANGE - Global Change and Sustainability Institute, Departamento Biologia Animal, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, edifício C2, Lisboa, 1749-016, Portugal
| | - Maud Charlery de la Masselière
- cE3c: Centre for Ecology, Evolution and Environmental Changes & CHANGE - Global Change and Sustainability Institute, Departamento Biologia Animal, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, edifício C2, Lisboa, 1749-016, Portugal
| | - Benoît Facon
- CBGP, INRAE, IRD, CIRAD, Institut Agro, University of Montpellier, 755 avenue du Campus Agropolis, CS 34988, Montferrier sur Lez cedex, 30016, France
| | - Lechosław Kuczyński
- Population Ecology Lab, Faculty of Biology, Institute of Environmental Biology, Adam Mickiewicz University, Poznań, Uniwersytetu Poznańskiego 6, Poznań, 61-614, Poland
| | - Jacek Radwan
- Evolutionary Biology Group, Faculty of Biology, Institute of Environmental Biology, Adam Mickiewicz University, Poznań, Uniwersytetu Poznańskiego 6, Poznań, 61-614, Poland
| | - Anna Skoracka
- Population Ecology Lab, Faculty of Biology, Institute of Environmental Biology, Adam Mickiewicz University, Poznań, Uniwersytetu Poznańskiego 6, Poznań, 61-614, Poland
| | - Sara Magalhães
- cE3c: Centre for Ecology, Evolution and Environmental Changes & CHANGE - Global Change and Sustainability Institute, Departamento Biologia Animal, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, edifício C2, Lisboa, 1749-016, Portugal
| |
Collapse
|
16
|
Headrick KC, Juenger TE, Heckman RW. Plant physical defenses contribute to a latitudinal gradient in resistance to insect herbivory within a widespread perennial grass. AMERICAN JOURNAL OF BOTANY 2024; 111:e16260. [PMID: 38031482 DOI: 10.1002/ajb2.16260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 10/23/2023] [Accepted: 10/24/2023] [Indexed: 12/01/2023]
Abstract
PREMISE Herbivore pressure can vary across the range of a species, resulting in different defensive strategies. If herbivory is greater at lower latitudes, plants may be better defended there, potentially driving a latitudinal gradient in defense. However, relationships that manifest across the entire range of a species may be confounded by differences within genetic subpopulations, which may obscure the drivers of these latitudinal gradients. METHODS We grew plants of the widespread perennial grass Panicum virgatum in a common garden that included genotypes from three genetic subpopulations spanning an 18.5° latitudinal gradient. We then assessed defensive strategies of these plants by measuring two physical resistance traits-leaf mass per area (LMA) and leaf ash, a proxy for silica-and multiple measures of herbivory by caterpillars of the generalist herbivore fall armyworm (Spodoptera frugiperda). RESULTS Across all genetic subpopulations, low-latitude plants experienced less herbivory than high-latitude plants. Within genetic subpopulations, however, this relationship was inconsistent-the most widely distributed and phenotypically variable subpopulation (Atlantic) exhibited more consistent latitudinal trends than either of the other two subpopulations. The two physical resistance traits, LMA and leaf ash, were both highly heritable and positively associated with resistance to different measures of herbivory across all subpopulations, indicating their importance in defense against herbivores. Again, however, these relationships were inconsistent within subpopulations. CONCLUSIONS Defensive gradients that occur across the entire species range may not arise within localized subpopulations. Thus, identifying the drivers of latitudinal gradients in herbivory defense may depend on adequately sampling the diversity within a species.
Collapse
Affiliation(s)
- Kevin C Headrick
- Department of Integrative Biology, University of Texas at Austin, Austin, TX, 78712, USA
| | - Thomas E Juenger
- Department of Integrative Biology, University of Texas at Austin, Austin, TX, 78712, USA
| | - Robert W Heckman
- Department of Integrative Biology, University of Texas at Austin, Austin, TX, 78712, USA
| |
Collapse
|
17
|
Vágási CI, Vincze O, Adámková M, Kauzálová T, Lendvai ÁZ, Pătraş LI, Pénzes J, Pap PL, Albrecht T, Tomášek O. Songbirds avoid the oxidative stress costs of high blood glucose levels: a comparative study. J Exp Biol 2024; 227:jeb246848. [PMID: 38054362 DOI: 10.1242/jeb.246848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Accepted: 11/29/2023] [Indexed: 12/07/2023]
Abstract
Chronically high blood glucose levels (hyperglycaemia) can compromise healthy ageing and lifespan at the individual level. Elevated oxidative stress can play a central role in hyperglycaemia-induced pathologies. Nevertheless, the lifespan of birds shows no species-level association with blood glucose. This suggests that the potential pathologies of high blood glucose levels can be avoided by adaptations in oxidative physiology at the macroevolutionary scale. However, this hypothesis remains unexplored. Here, we examined this hypothesis using comparative analyses controlled for phylogeny, allometry and fecundity based on data from 51 songbird species (681 individuals with blood glucose data and 1021 individuals with oxidative state data). We measured blood glucose at baseline and after stress stimulus and computed glucose stress reactivity as the magnitude of change between the two time points. We also measured three parameters of non-enzymatic antioxidants (uric acid, total antioxidants and glutathione) and a marker of oxidative lipid damage (malondialdehyde). We found no clear evidence for blood glucose concentration being correlated with either antioxidant or lipid damage levels at the macroevolutionary scale, as opposed to the hypothesis postulating that high blood glucose levels entail oxidative costs. The only exception was the moderate evidence for species with a stronger stress-induced increase in blood glucose concentration evolving moderately lower investment into antioxidant defence (uric acid and glutathione). Neither baseline nor stress-induced glucose levels were associated with oxidative physiology. Our findings support the hypothesis that birds evolved adaptations preventing the (glyc)oxidative costs of high blood glucose observed at the within-species level. Such adaptations may explain the decoupled evolution of glycaemia and lifespan in birds and possibly the paradoxical combination of long lifespan and high blood glucose levels relative to mammals.
Collapse
Affiliation(s)
- Csongor I Vágási
- Evolutionary Ecology Group, Centre for Systems Biology, Biodiversity and Bioresources, Hungarian Department of Biology and Ecology, Babeş-Bolyai University, 400006 Cluj-Napoca, Romania
| | - Orsolya Vincze
- Evolutionary Ecology Group, Centre for Systems Biology, Biodiversity and Bioresources, Hungarian Department of Biology and Ecology, Babeş-Bolyai University, 400006 Cluj-Napoca, Romania
- Wetland Ecology Research Group, HUN-REN Centre for Ecological Research, Institute of Aquatic Ecology, 4026 Debrecen, Hungary
| | - Marie Adámková
- Institute of Vertebrate Biology of the Czech Academy of Sciences, 60300 Brno, Czech Republic
- Department of Botany and Zoology, Faculty of Science, Masaryk University, 61137 Brno, Czech Republic
| | - Tereza Kauzálová
- Institute of Vertebrate Biology of the Czech Academy of Sciences, 60300 Brno, Czech Republic
| | - Ádám Z Lendvai
- Department of Evolutionary Zoology, University of Debrecen, 4032 Debrecen, Hungary
| | - Laura I Pătraş
- Department of Molecular Biology and Biotechnology, Centre of Systems Biology, Biodiversity and Bioresources, Babeş-Bolyai University, 400006 Cluj-Napoca, Romania
| | - Janka Pénzes
- Evolutionary Ecology Group, Centre for Systems Biology, Biodiversity and Bioresources, Hungarian Department of Biology and Ecology, Babeş-Bolyai University, 400006 Cluj-Napoca, Romania
| | - Péter L Pap
- Evolutionary Ecology Group, Centre for Systems Biology, Biodiversity and Bioresources, Hungarian Department of Biology and Ecology, Babeş-Bolyai University, 400006 Cluj-Napoca, Romania
| | - Tomáš Albrecht
- Institute of Vertebrate Biology of the Czech Academy of Sciences, 60300 Brno, Czech Republic
- Department of Zoology, Faculty of Science, Charles University, 12800 Prague 2, Czech Republic
| | - Oldřich Tomášek
- Institute of Vertebrate Biology of the Czech Academy of Sciences, 60300 Brno, Czech Republic
- Department of Botany and Zoology, Faculty of Science, Masaryk University, 61137 Brno, Czech Republic
| |
Collapse
|
18
|
Kalirad A, Sommer RJ. Spatial and temporal heterogeneity alter the cost of plasticity in Pristionchus pacificus. PLoS Comput Biol 2024; 20:e1011823. [PMID: 38289972 PMCID: PMC10857712 DOI: 10.1371/journal.pcbi.1011823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 02/09/2024] [Accepted: 01/11/2024] [Indexed: 02/01/2024] Open
Abstract
Phenotypic plasticity, the ability of a single genotype to produce distinct phenotypes under different environmental conditions, has become a leading concept in ecology and evolutionary biology, with the most extreme examples being the formation of alternative phenotypes (polyphenisms). However, several aspects associated with phenotypic plasticity remain controversial, such as the existence of associated costs. While already predicted by some of the pioneers of plasticity research, i.e. Schmalhausen and Bradshaw, experimental and theoretical approaches have provided limited support for the costs of plasticity. In experimental studies, one common restriction is the measurement of all relevant parameters over long time periods. Similarly, theoretical studies rarely use modelling approaches that incorporate specific experimentally-derived fitness parameters. Therefore, the existence of the costs of plasticity remains disputed. Here, we provide an integrative approach to understand the cost of adaptive plasticity and its ecological ramifications, by combining laboratory data from the nematode plasticity model system Pristionchus pacificus with a stage-structured population model. Taking advantage of measurements of two isogenic strains grown on two distinct diets, we illustrate how spatial and temporal heterogeneity with regard to the distribution of resources on a metapopulation can alter the outcome of the competition and alleviate the realized cost of plasticity.
Collapse
Affiliation(s)
- Ata Kalirad
- Department for Integrative Evolutionary Biology, Max Planck Institute for Biology Tübingen, Tübingen, Germany
| | - Ralf J. Sommer
- Department for Integrative Evolutionary Biology, Max Planck Institute for Biology Tübingen, Tübingen, Germany
| |
Collapse
|
19
|
Journé V, Hacket-Pain A, Bogdziewicz M. Evolution of masting in plants is linked to investment in low tissue mortality. Nat Commun 2023; 14:7998. [PMID: 38042862 PMCID: PMC10693562 DOI: 10.1038/s41467-023-43616-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Accepted: 11/14/2023] [Indexed: 12/04/2023] Open
Abstract
Masting, a variable and synchronized variation in reproductive effort is a prevalent strategy among perennial plants, but the factors leading to interspecific differences in masting remain unclear. Here, we investigate interannual patterns of reproductive investment in 517 species of terrestrial perennial plants, including herbs, graminoids, shrubs, and trees. We place these patterns in the context of the plants' phylogeny, habitat, form and function. Our findings reveal that masting is widespread across the plant phylogeny. Nonetheless, reversion from masting to regular seed production is also common. While interannual variation in seed production is highest in temperate and boreal zones, our analysis controlling for environment and phylogeny indicates that masting is more frequent in species that invest in tissue longevity. Our modeling exposes masting-trait relationships that would otherwise remain hidden and provides large-scale evidence that the costs of delayed reproduction play a significant role in the evolution of variable reproduction in plants.
Collapse
Affiliation(s)
- Valentin Journé
- Forest Biology Center, Institute of Environmental Biology, Faculty of Biology, Adam Mickiewicz University, Uniwersytetu Poznańskiego 6, 61-614, Poznan, Poland.
| | - Andrew Hacket-Pain
- Department of Geography and Planning, School of Environmental Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Michał Bogdziewicz
- Forest Biology Center, Institute of Environmental Biology, Faculty of Biology, Adam Mickiewicz University, Uniwersytetu Poznańskiego 6, 61-614, Poznan, Poland.
| |
Collapse
|
20
|
Brian JI, Catford JA. A mechanistic framework of enemy release. Ecol Lett 2023; 26:2147-2166. [PMID: 37921034 DOI: 10.1111/ele.14329] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Accepted: 10/03/2023] [Indexed: 11/04/2023]
Abstract
The enemy release hypothesis (ERH) is the best-known hypothesis explaining high performance (e.g. rapid population growth) of exotic species. However, the current framing of the ERH does not explicitly link evidence of enemy release with exotic performance. This leads to uncertainty regarding the role of enemy release in biological invasions. Here, we demonstrate that the effect of enemy release on exotic performance is the product of three factors: enemy impact, enemy diversity, and host adaptation. These factors are modulated by seven contexts: time since introduction, resource availability, phylogenetic relatedness of exotic and native species, host-enemy asynchronicity, number of introduction events, type of enemy, and strength of growth-defence trade-offs. ERH-focused studies frequently test different factors under different contexts. This can lead to inconsistent findings, which typifies current evidence for the ERH. For example, over 80% of meta-analyses fail to consider ecological contexts which can alter study findings; we demonstrate this by re-analysing a recent ERH synthesis. Structuring the ERH around factors and contexts promotes generalisable predictions about when and where exotic species may benefit from enemy release, empowering effective management. Our mechanistic factor-context framework clearly lays out the evidence required to support the ERH, unifies many enemy-related invasion hypotheses, and enhances predictive capacity.
Collapse
Affiliation(s)
- Joshua I Brian
- Department of Geography, King's College London, London, UK
| | - Jane A Catford
- Department of Geography, King's College London, London, UK
- Fenner School of Environment & Society, The Australian National University, Canberra, Australia
- School of Agriculture, Food and Ecosystem Sciences, The University of Melbourne, Parkville, Australia
| |
Collapse
|
21
|
Graham CDK, Forrestel EJ, Schilmiller AL, Zemenick AT, Weber MG. Evolutionary signatures of a trade-off in direct and indirect defenses across the wild grape genus, Vitis. Evolution 2023; 77:2301-2313. [PMID: 37527551 DOI: 10.1093/evolut/qpad140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 07/17/2023] [Accepted: 07/31/2023] [Indexed: 08/03/2023]
Abstract
Evolutionary correlations between chemical defense and protection by mutualist bodyguards have been long predicted, but tests of these patterns remain rare. We use a phylogenetic framework to test for evolutionary correlations indicative of trade-offs or synergisms between direct defense in the form of plant secondary metabolism and indirect defense in the form of leaf domatia, across 33 species in the wild grape genus, Vitis. We also performed a bioassay with a generalist herbivore to associate our chemical phenotypes with herbivore palatability. Finally, we tested whether defensive traits correlated with the average abiotic characteristics of each species' contemporary range and whether these correlations were consistent with plant defense theory. We found a negative evolutionary correlation between domatia size and the diversity of secondary metabolites in Vitis leaf tissue across the genus, and also that leaves with a higher diversity and richness of secondary metabolites were less palatable to a generalist herbivore, consistent with a trade-off in chemical and mutualistic defense investment. Predictions from plant defense theory were not supported by associations between investment in defense phenotypes and abiotic variables. Our work demonstrates an evolutionary pattern indicative of a trade-off between indirect and direct defense strategies across the Vitis genus.
Collapse
Affiliation(s)
- Carolyn D K Graham
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI, United States
| | - Elisabeth J Forrestel
- Department of Viticulture and Enology, University of California-Davis, Davis, CA, United States
| | - Anthony L Schilmiller
- Mass Spectrometry and Metabolomics Core, Michigan State University, East Lansing, MI, United States
| | - Ash T Zemenick
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI, United States
- Department of Viticulture and Enology, University of California-Davis, Davis, CA, United States
| | - Marjorie G Weber
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI, United States
| |
Collapse
|
22
|
Martínez-Vilalta J, García-Valdés R, Jump A, Vilà-Cabrera A, Mencuccini M. Accounting for trait variability and coordination in predictions of drought-induced range shifts in woody plants. THE NEW PHYTOLOGIST 2023; 240:23-40. [PMID: 37501525 DOI: 10.1111/nph.19138] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Accepted: 06/20/2023] [Indexed: 07/29/2023]
Abstract
Functional traits offer a promising avenue to improve predictions of species range shifts under climate change, which will entail warmer and often drier conditions. Although the conceptual foundation linking traits with plant performance and range shifts appears solid, the predictive ability of individual traits remains generally low. In this review, we address this apparent paradox, emphasizing examples of woody plants and traits associated with drought responses at the species' rear edge. Low predictive ability reflects the fact not only that range dynamics tend to be complex and multifactorial, as well as uncertainty in the identification of relevant traits and limited data availability, but also that trait effects are scale- and context-dependent. The latter results from the complex interactions among traits (e.g. compensatory effects) and between them and the environment (e.g. exposure), which ultimately determine persistence and colonization capacity. To confront this complexity, a more balanced coverage of the main functional dimensions involved (stress tolerance, resource use, regeneration and dispersal) is needed, and modelling approaches must be developed that explicitly account for: trait coordination in a hierarchical context; trait variability in space and time and its relationship with exposure; and the effect of biotic interactions in an ecological community context.
Collapse
Affiliation(s)
- Jordi Martínez-Vilalta
- CREAF, E08193, Bellaterra (Cerdanyola del Vallès), Catalonia, Spain
- Universitat Autònoma de Barcelona, E08193, Bellaterra (Cerdanyola del Vallès), Catalonia, Spain
| | - Raúl García-Valdés
- CREAF, E08193, Bellaterra (Cerdanyola del Vallès), Catalonia, Spain
- Forest Science and Technology Centre of Catalonia (CTFC), E25280, Solsona, Spain
- Department of Biology, Geology, Physics and Inorganic Chemistry, School of Experimental Sciences and Technology, Rey Juan Carlos University, E28933, Móstoles, Madrid, Spain
| | - Alistair Jump
- Biological and Environmental Sciences, University of Stirling, FK9 4LA, Stirling, UK
| | - Albert Vilà-Cabrera
- CREAF, E08193, Bellaterra (Cerdanyola del Vallès), Catalonia, Spain
- Biological and Environmental Sciences, University of Stirling, FK9 4LA, Stirling, UK
| | - Maurizio Mencuccini
- CREAF, E08193, Bellaterra (Cerdanyola del Vallès), Catalonia, Spain
- ICREA, Pg. Lluís Companys 23, E08010, Barcelona, Spain
| |
Collapse
|
23
|
Gelambi M, Whitehead SR. Multiscale variability in nutrients and secondary metabolites in a bat-dispersed neotropical fruit. Ecol Evol 2023; 13:e10453. [PMID: 37664504 PMCID: PMC10474796 DOI: 10.1002/ece3.10453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 07/31/2023] [Accepted: 08/15/2023] [Indexed: 09/05/2023] Open
Abstract
Ripe fleshy fruits contain not only nutrients but also a diverse array of secondary metabolites. Nutrients serve as a reward for mutualists, whereas defensive metabolites protect the fruit against pests and predators. The composition of these chemical traits is highly variable, both across different plants and even within repeating structures on the same individual plant. This intraspecific and intraindividual variation has important fitness consequences for both plants and animals, yet patterns of variation and covariation in nutrients and secondary metabolites are not well understood, especially at smaller scales. Here, we investigate the multiscale variation and covariation between nutrients and defensive metabolites in Piper sancti-felicis ripe fruits. Means and measures of variation of sugars, proteins, phenolics, and alkenylphenols vary greatly among plants, and at least 50% of the trait variation occurs at the intraindividual level. Also, we found that proteins, but not sugars, were correlated with phenolics and alkenylphenols at multiple scales, suggesting trait variation in protein content may be more constrained than sugars. Our findings emphasize the importance of examining patterns across scales and provide the groundwork to better understand how complex patterns of variation and covariation in nutrients and defensive metabolites shape ecological interactions surrounding fruits.
Collapse
Affiliation(s)
- Mariana Gelambi
- Department of Biological SciencesVirginia Polytechnic Institute and State UniversityBlacksburgVirginiaUSA
- La Selva Biological StationOrganization for Tropical StudiesPuerto Viejo de SarapiquíHeredia ProvinceCosta Rica
| | - Susan R. Whitehead
- Department of Biological SciencesVirginia Polytechnic Institute and State UniversityBlacksburgVirginiaUSA
- La Selva Biological StationOrganization for Tropical StudiesPuerto Viejo de SarapiquíHeredia ProvinceCosta Rica
| |
Collapse
|
24
|
Kirk MA, Reider KE, Lackey ACR, Thomas SA, Whiteman HH. The role of environmental variation in mediating fitness trade-offs for an amphibian polyphenism. J Anim Ecol 2023; 92:1815-1827. [PMID: 37353993 DOI: 10.1111/1365-2656.13974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Accepted: 06/05/2023] [Indexed: 06/25/2023]
Abstract
Fitness trade-offs are a foundation of ecological and evolutionary theory because trade-offs can explain life history variation, phenotypic plasticity, and the existence of polyphenisms. Using a 32-year mark-recapture dataset on lifetime fitness for 1093 adult Arizona tiger salamanders (Ambystoma mavortium nebulosum) from a high elevation, polyphenic population, we evaluated the extent to which two life history morphs (aquatic paedomorphs vs. terrestrial metamorphs) exhibited fitness trade-offs in breeding and body condition with respect to environmental variation (e.g. climate) and internal state-based variables (e.g. age). Both morphs displayed a similar response to higher probabilities of breeding during years of high spring precipitation (i.e. not indicative of a morph-specific fitness trade-off). There were likely no climate-induced fitness trade-offs on breeding state for the two life history morphs because precipitation and water availability are vital to amphibian reproduction. Body condition displayed a contrasting response for the two morphs that was indicative of a climate-induced fitness trade-off. While metamorphs exhibited a positive relationship with summer snowpack conditions, paedomorphs were unaffected. Fitness trade-offs from summer snowpack are likely due to extended hydroperiods in temporary ponds, where metamorphs gain a fitness advantage during the summer growing season by exploiting resources that are unavailable to paeodomorphs. However, paedomorphs appear to have the overwintering fitness advantage because they consistently had higher body condition than metamorphs at the start of the summer growing season. Our results reveal that climate and habitat type (metamorphs as predominately terrestrial, paedomorphs as fully aquatic) interact to confer different advantages for each morph. These results advance our current understanding of fitness trade-offs in this well-studied polyphenic amphibian by integrating climate-based mechanisms. Our conclusions prompt future studies to explore how climatic variation can maintain polyphenisms and promote life history diversity, as well as the implications of climate change for polyphenisms.
Collapse
Affiliation(s)
- Mark A Kirk
- Watershed Studies Institute and Department of Biological Sciences, Murray State University, Murray, Kentucky, USA
- Environmental Science and Sustainability Department, Allegheny College, Meadville, Pennsylvania, USA
| | - Kelsey E Reider
- Department of Biology, James Madison University, Harrisonburg, Virginia, USA
| | - Alycia C R Lackey
- Department of Biology, University of Louisville, Louisville, Kentucky, USA
| | - Scott A Thomas
- Watershed Studies Institute and Department of Biological Sciences, Murray State University, Murray, Kentucky, USA
| | - Howard H Whiteman
- Watershed Studies Institute and Department of Biological Sciences, Murray State University, Murray, Kentucky, USA
- Rocky Mountain Biological Laboratory, Gothic, Colorado, USA
| |
Collapse
|
25
|
Oakley CG, Schemske DW, McKay JK, Ågren J. Ecological genetics of local adaptation in Arabidopsis: An 8-year field experiment. Mol Ecol 2023; 32:4570-4583. [PMID: 37317048 DOI: 10.1111/mec.17045] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 05/16/2023] [Accepted: 05/30/2023] [Indexed: 06/16/2023]
Abstract
There is considerable evidence for local adaptation in nature, yet important questions remain regarding its genetic basis. How many loci are involved? What are their effect sizes? What is the relative importance of conditional neutrality versus genetic trade-offs? Here we address these questions in the self-pollinating, annual plant Arabidopsis thaliana. We used 400 recombinant inbred lines (RILs) derived from two locally adapted populations in Italy and Sweden, grew the RILs and parents at the parental locations, and mapped quantitative trait loci (QTL) for mean fitness (fruits/seedling planted). We previously published results from the first 3 years of the study, and here add five additional years, providing a unique opportunity to assess how temporal variation in selection might affect QTL detection and classification. We found 10 adaptive and one maladaptive QTL in Italy, and six adaptive and four maladaptive QTL in Sweden. The discovery of maladaptive QTL at both sites suggests that even locally adapted populations are not always at their genotypic optimum. Mean effect sizes for adaptive QTL, 0.97 and 0.55 fruits in Italy and Sweden, respectively, were large relative to the mean fitness of the RILs (approximately 8 fruits/seedling planted at both sites). Both genetic trade-offs (four cases) and conditional neutrality (seven cases) contribute to local adaptation in this system. The 8-year dataset provided greater power to detect QTL and to estimate their locations compared to our previous 3-year study, identifying one new genetic trade-off and resolving one genetic trade-off into two conditionally adaptive QTL.
Collapse
Affiliation(s)
- Christopher G Oakley
- Department of Botany and Plant Pathology, and the Center for Plant Biology, Purdue University, West Lafayette, Indiana, USA
| | - Douglas W Schemske
- Department of Plant Biology and W. K. Kellogg Biological Station, Michigan State University, East Lansing, Michigan, USA
| | - John K McKay
- College of Agricultural Sciences, Colorado State University, Fort Collins, Colorado, USA
| | - Jon Ågren
- Plant Ecology and Evolution, Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
| |
Collapse
|
26
|
Sampedro L, Alía R. A claim for a 'next generation' of multisite range-wide forest genetic trials built on the legacy of ecological genetics to anticipate responses to climate. GLOBAL CHANGE BIOLOGY 2023. [PMID: 37317039 DOI: 10.1111/gcb.16816] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 05/16/2023] [Accepted: 05/22/2023] [Indexed: 06/16/2023]
Affiliation(s)
- Luis Sampedro
- Misión Biológica de Galicia (MBG-CSIC), Pontevedra, Spain
| | - Ricardo Alía
- Instituto de Ciencias Forestales (iCIFOR-INIA-CSIC), Madrid, Spain
| |
Collapse
|
27
|
Mohanbabu N, Veldhuis MP, Jung D, Ritchie ME. Integrating defense and leaf economic spectrum traits in a tropical savanna plant. FRONTIERS IN PLANT SCIENCE 2023; 14:1185616. [PMID: 37342149 PMCID: PMC10277734 DOI: 10.3389/fpls.2023.1185616] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Accepted: 05/22/2023] [Indexed: 06/22/2023]
Abstract
Introduction Allocation to plant defense traits likely depends on resource supply, herbivory, and other plant functional traits such as the leaf economic spectrum (LES) traits. Yet, attempts to integrate defense and resource acquisitive traits remain elusive. Methods We assessed intraspecific covariation between different defense and LES traits in a widely distributed tropical savanna herb, Solanum incanum, a unique model species for studying allocations to physical, chemical, and structural defenses to mammalian herbivory. Results We found that in a multivariate trait space, the structural defenses - lignin and cellulose - were positively related to the resource conservative traits - low SLA and low leaf N. Phenolic content, a chemical defense, was positively associated with resource acquisitive traits - high SLA and high leaf N - while also being associated with an independent third component axis. Both principal components 1 and 3 were not associated with resource supply and herbivory intensity. In contrast, spine density - a physical defense - was orthogonal to the LES axis and positively associated with soil P and herbivory intensity. Discussion These results suggest a hypothesized "pyramid" of trade-offs in allocation to defense along the LES and herbivory intensity axes. Therefore, future attempts to integrate defense traits with the broader plant functional trait framework, such as the LES, needs a multifaceted approach that accounts for unique influences of resource acquisitive traits and herbivory risk.
Collapse
Affiliation(s)
- Neha Mohanbabu
- Department of Biology, Syracuse University, Syracuse, NY, United States
| | - Michiel P. Veldhuis
- Institute of Environmental Sciences, Universiteit Leiden, Leiden, The Netherlands
| | - Dana Jung
- Department of Biology, Syracuse University, Syracuse, NY, United States
| | - Mark E. Ritchie
- Department of Biology, Syracuse University, Syracuse, NY, United States
| |
Collapse
|
28
|
Mason CJ, Peiffer M, Hoover K, Felton G. Tomato Chemical Defenses Intensify Corn Earworm (Helicoverpa zea) Mortality from Opportunistic Bacterial Pathogens. J Chem Ecol 2023; 49:313-324. [PMID: 36964896 DOI: 10.1007/s10886-023-01420-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 02/21/2023] [Accepted: 03/13/2023] [Indexed: 03/26/2023]
Abstract
Insect herbivores face multiple challenges to their ability to grow and reproduce. Plants can produce a series of defenses that disrupt and damage the herbivore digestive system, which are heightened upon injury by insect feeding. Additionally, insects face threats from virulent microorganisms that can incur their own set of potential costs to hosts. Microorganisms that invade through the digestive system may function in concert with defenses generated by plants, creating combined assailments on host insects. In our study, we evaluated how tomato defenses interact with an enteric bacterial isolate, Serratia marcescens, in the corn earworm (Helicoverpa zea). We performed bioassays using different tomato cultivars that were induced by methyl jasmonate and larvae orally inoculated with a S. marcescens isolate. Untreated corn earworm larval mortality was low on constitutive tomato, while larvae inoculated with S. marcescens exhibited > 50% mortality within 5 days. Induction treatments elevated both control mortality (~ 45%) and in combination with S. marcescens (> 95%). Larvae also died faster when encountering induced defenses and Serratia. Using a tomato mutant, foliar polyphenol oxidase activity likely had stronger impacts on S. marcescens-mediated larval mortality. Induction treatments also elevated the number of bacterial colony-forming units in the hemolymph of larvae inoculated with Serratia. Larval mortality by S. marcescens was low (< 10%) on artificial diets. Our results demonstrate that plant chemical defenses enhance larval mortality from an opportunistic gut microbe. We propose that the combined damage from both the plant and microbial agent overwhelm the herbivore to increase mortality rates and expedite host death.
Collapse
Affiliation(s)
- Charles J Mason
- 501 ASI Building Department of Entomology, The Pennsylvania State University, University Park, PA, 16823, USA.
- Tropical Pest Genetics and Molecular Biology Research Unit, Daniel K Inouye U.S. Pacific Basin Agricultural Research Center, Agricultural Research Service, USDA, 64 Nowelo Street, Hilo, HI, 96720, USA.
| | - Michelle Peiffer
- 501 ASI Building Department of Entomology, The Pennsylvania State University, University Park, PA, 16823, USA
| | - Kelli Hoover
- 501 ASI Building Department of Entomology, The Pennsylvania State University, University Park, PA, 16823, USA
| | - Gary Felton
- 501 ASI Building Department of Entomology, The Pennsylvania State University, University Park, PA, 16823, USA
| |
Collapse
|
29
|
Williamson JL, Linck EB, Bautista E, Smiley A, McGuire JA, Dudley R, Witt CC. Hummingbird blood traits track oxygen availability across space and time. Ecol Lett 2023. [PMID: 37178017 DOI: 10.1111/ele.14235] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 03/20/2023] [Accepted: 04/13/2023] [Indexed: 05/15/2023]
Abstract
Predictable trait variation across environments suggests shared adaptive responses via repeated genetic evolution, phenotypic plasticity or both. Matching of trait-environment associations at phylogenetic and individual scales implies consistency between these processes. Alternatively, mismatch implies that evolutionary divergence has changed the rules of trait-environment covariation. Here we tested whether species adaptation alters elevational variation in blood traits. We measured blood for 1217 Andean hummingbirds of 77 species across a 4600-m elevational gradient. Unexpectedly, elevational variation in haemoglobin concentration ([Hb]) was scale independent, suggesting that physics of gas exchange, rather than species differences, determines responses to changing oxygen pressure. However, mechanisms of [Hb] adjustment did show signals of species adaptation: Species at either low or high elevations adjusted cell size, whereas species at mid-elevations adjusted cell number. This elevational variation in red blood cell number versus size suggests that genetic adaptation to high altitude has changed how these traits respond to shifts in oxygen availability.
Collapse
Affiliation(s)
- Jessie L Williamson
- Museum of Southwestern Biology, University of New Mexico, Albuquerque, New Mexico, USA
- Department of Biology, University of New Mexico, Albuquerque, New Mexico, USA
- Cornell Lab of Ornithology, Cornell University, Ithaca, New York, USA
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, New York, USA
- Cornell University Museum of Vertebrates, Cornell University, Ithaca, New York, USA
| | - Ethan B Linck
- Museum of Southwestern Biology, University of New Mexico, Albuquerque, New Mexico, USA
- Department of Biology, University of New Mexico, Albuquerque, New Mexico, USA
| | - Emil Bautista
- Centro de Ornitología y Biodiversidad (CORBIDI), Lima, Peru
| | - Ashley Smiley
- Museum of Southwestern Biology, University of New Mexico, Albuquerque, New Mexico, USA
- Department of Biology, University of New Mexico, Albuquerque, New Mexico, USA
| | - Jimmy A McGuire
- Museum of Vertebrate Zoology, University of California, Berkeley, California, USA
- Department of Integrative Biology, University of California, Berkeley, California, USA
| | - Robert Dudley
- Museum of Vertebrate Zoology, University of California, Berkeley, California, USA
- Department of Integrative Biology, University of California, Berkeley, California, USA
| | - Christopher C Witt
- Museum of Southwestern Biology, University of New Mexico, Albuquerque, New Mexico, USA
- Department of Biology, University of New Mexico, Albuquerque, New Mexico, USA
| |
Collapse
|
30
|
Razzaque S, Heckman RW, Juenger TE. Seed size variation impacts local adaptation and life-history strategies in a perennial grass. Proc Biol Sci 2023; 290:20222460. [PMID: 37132240 PMCID: PMC10154936 DOI: 10.1098/rspb.2022.2460] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Accepted: 04/03/2023] [Indexed: 05/04/2023] Open
Abstract
Seed mass is an ecologically important trait that often differs considerably among ecotypes. Yet, because few studies examine the impacts of seed mass on adult life-history traits, its role in local adaptation is unclear. In this study, using accessions of Panicum hallii that spanned the two major ecotypes, we examined whether covariation between seed mass, seedling and reproductive traits impacts ecotypic divergence and local adaptation. The perennial grass P. hallii has two distinct ecotypes-a large-seeded upland ecotype adapted to xeric environments and a small-seeded lowland ecotype adapted to mesic environments. In the greenhouse, seed mass varied greatly across P. hallii genotypes in a manner consistent with ecotypic divergence. Seed mass covaried significantly with several seedling and reproductive traits. At field sites representing the habitats of the two ecotypes, seed mass had different impacts on seedling and adult recruitment: selection favoured large seeds in upland habitat and small seeds in lowland habitat, which was consistent with local adaptation. By demonstrating the central role of seed mass in ecotypic differences in P. hallii and its importance to seedling and adult recruitment under field conditions, these studies show that early life-history traits can promote local adaptation and potentially explain ecotype formation.
Collapse
Affiliation(s)
- Samsad Razzaque
- Department of Integrative Biology, The University of Texas at Austin, Austin, TX 78712, USA
| | - Robert W. Heckman
- Department of Integrative Biology, The University of Texas at Austin, Austin, TX 78712, USA
| | - Thomas E. Juenger
- Department of Integrative Biology, The University of Texas at Austin, Austin, TX 78712, USA
| |
Collapse
|
31
|
Kalske A, Kessler A. Herbivory selects for tolerance and constitutive defence across stages of community succession. Proc Biol Sci 2023; 290:20222458. [PMID: 36787795 PMCID: PMC9928524 DOI: 10.1098/rspb.2022.2458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Accepted: 01/13/2023] [Indexed: 02/16/2023] Open
Abstract
Plants defend themselves from herbivory by either reducing damage (resistance) or minimizing its negative fitness effects with compensatory growth (tolerance). Herbivore pressure can fluctuate from year to year in an early secondary successional community, which can create temporal variation in selection for defence traits. We manipulated insect herbivory and successional age of the community as agents of natural selection in replicated common gardens with the perennial herb Solidago altissima. In these genotypic selection experiments, herbivory consistently selected for better defended plants in both successional communities. Herbivore suppression increased plant survival and the probability of flowering only in mid-succession. Despite these substantial differences in the effects of herbivory between early and mid-succession, the selection on defence traits did not change. Succession affected selection only on aboveground biomass, with positive selection in early but not mid-succession, suggesting an important role of competition in the selective environment. These results demonstrate that changes in the community that affect key life-history traits in an individual species can occur over very short timescales in a dynamic secondary successional environment. The resulting community context-driven variation in natural selection may be an important, yet overlooked, contributor to adaptive mosaics across populations.
Collapse
Affiliation(s)
- Aino Kalske
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY 14853, USA
| | - André Kessler
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY 14853, USA
| |
Collapse
|
32
|
Pasques O, Munné-Bosch S. Physiological mechanisms underlying extreme longevity in mountain pine trees. PLANT PHYSIOLOGY 2023; 191:974-985. [PMID: 36440969 PMCID: PMC9922391 DOI: 10.1093/plphys/kiac540] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Accepted: 10/31/2022] [Indexed: 06/16/2023]
Abstract
Ancient trees are life history longevity winners that mostly persist in remote and environmentally harsh mountainous areas. Here, we performed a multifeature analysis in a protected mature mountain pine (Pinus uncinata) forest to identify the morphological and physiological traits that make these trees unique. We compared the physiology of meristematic and somatic tissues (apical buds and needles, respectively) from juvenile, mature young, mature old, and mature ancient trees under cold stress and nonstress conditions. We successfully identified key morphological features of extreme longevity at the organism level, as well as various growth, vigor, stress, and dormancy markers underlying extreme longevity in old and ancient trees. Results indicated that evolution has exerted selective pressure on specific physiological traits that make trees become longevity winners (<0.1% of the tree population were ancient trees, with an average trunk diameter >100 cm and an estimated age of 700 years). Traits entailing longevity not only included apical dominance loss, epicormic growth, and modular senescence, but also an extreme plasticity in both meristematic and somatic tissues (buds and needles, respectively), as shown by various physiological markers. In conclusion, ancient trees are oddities that not only possess a unique ecological value but also show divergent physiological behaviors selected during their evolution to allow them to cope with adversities and attain long life.
Collapse
Affiliation(s)
- Ot Pasques
- Department of Evolutionary Biology, Ecology and Environmental Sciences, University of Barcelona, Barcelona 08028, Spain
| | - Sergi Munné-Bosch
- Department of Evolutionary Biology, Ecology and Environmental Sciences, University of Barcelona, Barcelona 08028, Spain
- Research Institute in Biodiversity (IRBio), University of Barcelona, Barcelona 08028, Spain
| |
Collapse
|
33
|
Edwards CB, Ellner SP, Agrawal AA. Plant defense synergies and antagonisms affect performance of specialist herbivores of common milkweed. Ecology 2023; 104:e3915. [PMID: 36336890 DOI: 10.1002/ecy.3915] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Accepted: 09/27/2022] [Indexed: 11/09/2022]
Abstract
As a general rule, plants defend against herbivores with multiple traits. The defense synergy hypothesis posits that some traits are more effective when co-expressed with others compared to their independent efficacy. However, this hypothesis has rarely been tested outside of phytochemical mixtures, and seldom under field conditions. We tested for synergies between multiple defense traits of common milkweed (Asclepias syriaca) by assaying the performance of two specialist chewing herbivores on plants in natural populations. We employed regression and a novel application of random forests to identify synergies and antagonisms between defense traits. We found the first direct empirical evidence for two previously hypothesized defense synergies in milkweed (latex by secondary metabolites, latex by trichomes) and identified numerous other potential synergies and antagonisms. Our strongest evidence for a defense synergy was between leaf mass per area and low nitrogen content; given that these "leaf economic" traits typically covary in milkweed, a defense synergy could reinforce their co-expression. We report that each of the plant defense traits showed context-dependent effects on herbivores, and increased trait expression could well be beneficial to herbivores for some ranges of observed expression. The novel methods and findings presented here complement more mechanistic approaches to the study of plant defense diversity and provide some of the best evidence to date that multiple classes of plant defense synergize in their impact on insects. Plant defense synergies against highly specialized herbivores, as shown here, are consistent with ongoing reciprocal evolution between these antagonists.
Collapse
Affiliation(s)
- Collin B Edwards
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, New York, USA.,Department of Biology, Tufts University, Medford, Massachusetts, USA
| | - Stephen P Ellner
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, New York, USA
| | - Anurag A Agrawal
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, New York, USA
| |
Collapse
|
34
|
He T, Angessa TT, Li C. Pleiotropy Structures Plant Height and Seed Weight Scaling in Barley despite Long History of Domestication and Breeding Selection. PLANT PHENOMICS (WASHINGTON, D.C.) 2023; 5:0015. [PMID: 37040291 PMCID: PMC10076058 DOI: 10.34133/plantphenomics.0015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 11/27/2022] [Indexed: 06/19/2023]
Abstract
Size scaling describes the relative growth rates of different body parts of an organism following a positive correlation. Domestication and crop breeding often target the scaling traits in the opposite directions. The genetic mechanism of the size scaling influencing the pattern of size scaling remains unexplored. Here, we revisited a diverse barley (Hordeum vulgare L.) panel with genome-wide single-nucleotide polymorphisms (SNPs) profile and the measurement of their plant height and seed weight to explore the possible genetic mechanisms that may lead to a correlation of the two traits and the influence of domestication and breeding selection on the size scaling. Plant height and seed weight are heritable and remain positively correlated in domesticated barley regardless of growth type and habit. Genomic structural equation modeling systematically evaluated the pleiotropic effect of individual SNP on the plant height and seed weight within a trait correlation network. We discovered seventeen novel SNPs (quantitative trait locus) conferring pleiotropic effect on plant height and seed weight, involving genes with function in diverse traits related to plant growth and development. Linkage disequilibrium decay analysis revealed that a considerable proportion of genetic markers associated with either plant height or seed weight are closely linked in the chromosome. We conclude that pleiotropy and genetic linkage likely form the genetic bases of plant height and seed weight scaling in barley. Our findings contribute to understanding the heritability and genetic basis of size scaling and open a new venue for seeking the underlying mechanism of allometric scaling in plants.
Collapse
Affiliation(s)
- Tianhua He
- Western Crop Genetics Alliance, Agricultural Sciences, College of Science, Health, Engineering and Education, Murdoch University, Murdoch, WA, Australia
| | - Tefera Tolera Angessa
- Western Crop Genetics Alliance, Agricultural Sciences, College of Science, Health, Engineering and Education, Murdoch University, Murdoch, WA, Australia
| | - Chengdao Li
- Western Crop Genetics Alliance, Agricultural Sciences, College of Science, Health, Engineering and Education, Murdoch University, Murdoch, WA, Australia
- Agriculture and Food, Department of Primary Industries and Regional Development, South Perth, WA, Australia
| |
Collapse
|
35
|
Koptur S, Primoli AS, Pimienta MC. Defoliation in Perennial Plants: Predictable and Surprising Results in Senna spp. PLANTS (BASEL, SWITZERLAND) 2023; 12:587. [PMID: 36771669 PMCID: PMC9919507 DOI: 10.3390/plants12030587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 01/26/2023] [Accepted: 01/26/2023] [Indexed: 06/18/2023]
Abstract
When some plants are defoliated, they may suffer by reaching a smaller final size than if they had not been damaged. Other plants may compensate for damage, ending up the same size as if they had not been damaged. Still, others may overcompensate, ending up larger after defoliation than if they had been spared from damage. We investigated the response of Senna species (Fabaceae) to defoliation, comparing two native and several ornamental congeners, all of which grow locally in southern Florida. Many Senna spp. bear foliar nectaries as nutritional resources for beneficial insects that may, in exchange, protect them from herbivores. We grew five species from seed and subjected them to three levels of defoliation for a period of several months to measure effects of leaf area removal on plant height, number of leaves, and number of extrafloral nectaries. Only three of five species displayed shorter plant heights with greater levels of damage. Two species produced fewer new leaves with moderate to severe defoliation. In only one species, the number of extrafloral nectaries decreased with defoliation, suggesting that while extrafloral nectar production may be an inducible defense in some species, producing more nectaries in response to damage does not occur in these Senna species.
Collapse
|
36
|
Verslues PE, Bailey-Serres J, Brodersen C, Buckley TN, Conti L, Christmann A, Dinneny JR, Grill E, Hayes S, Heckman RW, Hsu PK, Juenger TE, Mas P, Munnik T, Nelissen H, Sack L, Schroeder JI, Testerink C, Tyerman SD, Umezawa T, Wigge PA. Burning questions for a warming and changing world: 15 unknowns in plant abiotic stress. THE PLANT CELL 2023; 35:67-108. [PMID: 36018271 PMCID: PMC9806664 DOI: 10.1093/plcell/koac263] [Citation(s) in RCA: 43] [Impact Index Per Article: 43.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Accepted: 08/21/2022] [Indexed: 05/08/2023]
Abstract
We present unresolved questions in plant abiotic stress biology as posed by 15 research groups with expertise spanning eco-physiology to cell and molecular biology. Common themes of these questions include the need to better understand how plants detect water availability, temperature, salinity, and rising carbon dioxide (CO2) levels; how environmental signals interface with endogenous signaling and development (e.g. circadian clock and flowering time); and how this integrated signaling controls downstream responses (e.g. stomatal regulation, proline metabolism, and growth versus defense balance). The plasma membrane comes up frequently as a site of key signaling and transport events (e.g. mechanosensing and lipid-derived signaling, aquaporins). Adaptation to water extremes and rising CO2 affects hydraulic architecture and transpiration, as well as root and shoot growth and morphology, in ways not fully understood. Environmental adaptation involves tradeoffs that limit ecological distribution and crop resilience in the face of changing and increasingly unpredictable environments. Exploration of plant diversity within and among species can help us know which of these tradeoffs represent fundamental limits and which ones can be circumvented by bringing new trait combinations together. Better defining what constitutes beneficial stress resistance in different contexts and making connections between genes and phenotypes, and between laboratory and field observations, are overarching challenges.
Collapse
Affiliation(s)
| | - Julia Bailey-Serres
- Department of Botany and Plant Sciences, Center for Plant Cell Biology, University of California, Riverside, California 92521, USA
| | - Craig Brodersen
- School of the Environment, Yale University, New Haven, Connecticut 06511, USA
| | - Thomas N Buckley
- Department of Plant Sciences, University of California, Davis, California 95616, USA
| | - Lucio Conti
- Department of Biosciences, University of Milan, Milan 20133, Italy
| | - Alexander Christmann
- School of Life Sciences, Technical University Munich, Freising-Weihenstephan 85354, Germany
| | - José R Dinneny
- Department of Biology, Stanford University, Stanford, California 94305, USA
| | - Erwin Grill
- School of Life Sciences, Technical University Munich, Freising-Weihenstephan 85354, Germany
| | - Scott Hayes
- Laboratory of Plant Physiology, Plant Sciences Group, Wageningen University and Research, Wageningen 6708 PB, The Netherlands
| | - Robert W Heckman
- Department of Integrative Biology, University of Texas at Austin, Austin, Texas 78712, USA
| | - Po-Kai Hsu
- Department of Cell and Developmental Biology, School of Biological Sciences, University of California San Diego, La Jolla, California 92093, USA
| | - Thomas E Juenger
- Department of Integrative Biology, University of Texas at Austin, Austin, Texas 78712, USA
| | - Paloma Mas
- Centre for Research in Agricultural Genomics (CRAG), CSIC-IRTA-UAB-UB, Barcelona 08193, Spain
- Consejo Superior de Investigaciones Científicas (CSIC), Barcelona 08028, Spain
| | - Teun Munnik
- Department of Plant Cell Biology, Green Life Sciences Cluster, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam NL-1098XH, The Netherlands
| | - Hilde Nelissen
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent 9052, Belgium
- VIB Center for Plant Systems Biology, Ghent 9052, Belgium
| | - Lawren Sack
- Department of Ecology and Evolutionary Biology, Institute of the Environment and Sustainability, University of California, Los Angeles, California 90095, USA
| | - Julian I Schroeder
- Department of Cell and Developmental Biology, School of Biological Sciences, University of California San Diego, La Jolla, California 92093, USA
| | - Christa Testerink
- Laboratory of Plant Physiology, Plant Sciences Group, Wageningen University and Research, Wageningen 6708 PB, The Netherlands
| | - Stephen D Tyerman
- ARC Center Excellence, Plant Energy Biology, School of Agriculture Food and Wine, University of Adelaide, Adelaide, South Australia 5064, Australia
| | - Taishi Umezawa
- Faculty of Agriculture, Tokyo University of Agriculture and Technology, Tokyo 6708 PB, Japan
| | - Philip A Wigge
- Leibniz-Institut für Gemüse- und Zierpflanzenbau, Großbeeren 14979, Germany
- Institute of Biochemistry and Biology, University of Potsdam, Potsdam 14476, Germany
| |
Collapse
|
37
|
Prabh N, Linnenbrink M, Jovicic M, Guenther A. Fast adjustment of pace-of-life and risk-taking to changes in food quality by altered gene expression in house mice. Ecol Lett 2023; 26:99-110. [PMID: 36366786 DOI: 10.1111/ele.14137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 10/06/2022] [Accepted: 10/09/2022] [Indexed: 11/13/2022]
Abstract
The pace-of-life syndrome hypothesis provides a framework for the adaptive integration of behaviour, physiology and life history between and within species. It suggests that behaviours involving a risk of death or injury should co-vary with a higher allocation to fast reproduction. Empirical support for this hypothesis is mixed, presumably because important influencing factors such as environmental variation, are usually neglected. By experimentally manipulating food quality of wild mice living under semi-natural conditions for three generations, we show that individuals adjust their life history strategies and risk-taking behaviours as well as trait covariation (Nindividuals = 1442). These phenotypic differences are correlated to differences in transcriptomic gene expression of primary metabolic processes in the liver while no changes in gene frequencies occurred. Our discussion emphasises the need to integrate the role of environmental conditions and phenotypic plasticity in shaping relationships among behaviour, physiology and life history in response to changing environmental conditions.
Collapse
Affiliation(s)
- Neel Prabh
- Max Planck Institute for Evolutionary Biology, Plön, Germany
| | | | - Milan Jovicic
- Max Planck Institute for Evolutionary Biology, Plön, Germany
| | - Anja Guenther
- Max Planck Institute for Evolutionary Biology, Plön, Germany
| |
Collapse
|
38
|
Zimmer C, Taff CC, Ardia DR, Rosvall KA, Kallenberg C, Bentz AB, Taylor AR, Johnson LS, Vitousek MN. Gene expression in the female tree swallow brain is associated with inter- and intra-population variation in glucocorticoid levels. Horm Behav 2023; 147:105280. [PMID: 36403365 DOI: 10.1016/j.yhbeh.2022.105280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2022] [Revised: 10/12/2022] [Accepted: 11/07/2022] [Indexed: 11/18/2022]
Abstract
Studies of the evolutionary causes and consequences of variation in circulating glucocorticoids (GCs) have begun to reveal how they are shaped by selection. Yet the extent to which variation in circulating hormones reflects variation in other important regulators of the hypothalamic-pituitary-adrenal (HPA) axis, and whether these relationships vary among populations inhabiting different environments, remain poorly studied. Here, we compare gene expression in the brain of female tree swallows (Tachycineta bicolor) from populations that breed in environments that differ in their unpredictability. We find evidence of inter-population variation in the expression of glucocorticoid and mineralocorticoid receptors in the hypothalamus, with the highest gene expression in a population from an extreme environment, and lower expression in a population from a more consistent environment as well as in birds breeding at an environmentally variable high-altitude site that are part of a population that inhabits a mixture of high and low altitude habitats. Within some populations, variation in circulating GCs predicted differences in gene expression, particularly in the hypothalamus. However, some patterns were present in all populations, whereas others were not. These results are consistent with the idea that some combination of local adaptation and phenotypic plasticity may modify components of the HPA axis affecting stress resilience. Our results also underscore that a comprehensive understanding of the function and evolution of the stress response cannot be gained from measuring circulating hormones alone, and that future studies that apply a more explicitly evolutionary approach to important regulatory traits are likely to provide significant insights.
Collapse
Affiliation(s)
- Cedric Zimmer
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY 14853, USA; Laboratoire d'Ethologie Expérimentale et Comparée, LEEC, Université Sorbonne Paris Nord, UR 4443, 93430 Villetaneuse, France.
| | - Conor C Taff
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY 14853, USA; Cornell Lab of Ornithology, Ithaca, NY 14850, USA
| | - Daniel R Ardia
- Department of Biology, Franklin and Marshall College, Lancaster, PA 17604, USA
| | - Kimberly A Rosvall
- Department of Biology, Indiana University Bloomington, Bloomington, IN 47405, USA
| | - Christine Kallenberg
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY 14853, USA
| | - Alexandra B Bentz
- Department of Biology, Indiana University Bloomington, Bloomington, IN 47405, USA; Department of Biology, University of Oklahoma, Norman, OK 73019, USA
| | - Audrey R Taylor
- Biological Sciences, University of Alaska Anchorage, Anchorage, AK 99508, USA
| | - L Scott Johnson
- Department of Biological Sciences, Towson University, Towson, MD 21252, USA
| | - Maren N Vitousek
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY 14853, USA; Cornell Lab of Ornithology, Ithaca, NY 14850, USA
| |
Collapse
|
39
|
Castro AA, Garland T, Ahmed S, Holt NC. Trade-offs in muscle physiology in selectively bred high runner mice. J Exp Biol 2022; 225:285903. [PMID: 36408738 PMCID: PMC9789404 DOI: 10.1242/jeb.244083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Accepted: 10/25/2022] [Indexed: 11/22/2022]
Abstract
A trade-off between locomotor speed and endurance occurs in various taxa, and is thought to be underpinned by a muscle-level trade-off. Among four replicate high runner (HR) lines of mice, selectively bred for voluntary wheel-running behavior, a negative correlation between average running speed and time spent running has evolved. We hypothesize that this trade-off is due to changes in muscle physiology. We studied the HR lines at generation 90, at which time one line (L3) is fixed for the mini-muscle phenotype, another is polymorphic (L6) and the others (L7, L8) lack mini-muscle individuals. We used in situ preparations to quantify the contractile properties of the triceps surae muscle complex. Maximal shortening velocity varied significantly, being lowest in mini-muscle mice (L3 mini=25.2 mm s-1, L6 mini=25.5 mm s-1), highest in normal-muscle mice L6 and L8 (40.4 and 50.3 mm s-1, respectively) and intermediate in normal-muscle L7 mice (37.2 mm s-1). Endurance, measured both as the slope of the decline in force and the proportion of initial force that could be sustained, also varied significantly. The slope was shallowest in mini-muscle mice (L3 mini=-0.00348, L6 mini=-0.00238), steepest in lines L6 and L8 (-0.01676 and -0.01853), and intermediate in L7 (-0.01145). Normalized sustained force was highest in mini-muscle mice (L3 mini=0.98, L6 mini=0.92) and lowest in L8 (0.36). There were significant, negative correlations between velocity and endurance metrics, indicating a muscle-level trade-off. However, this muscle-level trade-off does not seem to underpin the organismal-level speed and endurance trade-off previously reported as the ordering of the lines is reversed: the lines that run the fastest for the least time have the lowest muscle complex velocity and highest endurance.
Collapse
Affiliation(s)
- Alberto A. Castro
- Department of Evolution, Ecology, and Organismal Biology, University of California, Riverside, Riverside, CA 92521, USA
| | - Theodore Garland
- Department of Evolution, Ecology, and Organismal Biology, University of California, Riverside, Riverside, CA 92521, USA
| | - Saad Ahmed
- Department of Evolution, Ecology, and Organismal Biology, University of California, Riverside, Riverside, CA 92521, USA
| | - Natalie C. Holt
- Department of Evolution, Ecology, and Organismal Biology, University of California, Riverside, Riverside, CA 92521, USA,Author for correspondence ()
| |
Collapse
|
40
|
Costa e Silva J, Potts BM, Wiehl G, Prober SM. Linking leaf economic and hydraulic traits with early-age growth performance and survival of Eucalyptus pauciflora. FRONTIERS IN PLANT SCIENCE 2022; 13:973087. [PMID: 36426150 PMCID: PMC9679299 DOI: 10.3389/fpls.2022.973087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/19/2022] [Accepted: 10/03/2022] [Indexed: 06/16/2023]
Abstract
Selection on plant functional traits may occur through their direct effects on fitness (or a fitness component), or may be mediated by attributes of plant performance which have a direct impact on fitness. Understanding this link is particularly challenging for long-lived organisms, such as forest trees, where lifetime fitness assessments are rarely achievable, and performance features and fitness components are usually quantified from early-life history stages. Accordingly, we studied a cohort of trees from multiple populations of Eucalyptus pauciflora grown in a common-garden field trial established at the hot and dry end of the species distribution on the island of Tasmania, Australia. We related the within-population variation in leaf economic (leaf thickness, leaf area and leaf density) and hydraulic (stomatal density, stomatal length and vein density) traits, measured from two-year-old plants, to two-year growth performance (height and stem diameter) and to a fitness component (seven-year survival). When performance-trait relationships were modelled for all traits simultaneously, statistical support for direct effects on growth performance was only observed for leaf thickness and leaf density. Performance-based estimators of directional selection indicated that individuals with reduced leaf thickness and increased leaf density were favoured. Survival-performance relationships were consistent with size-dependent mortality, with fitness-based selection gradients estimated for performance measures providing evidence for directional selection favouring individuals with faster growth. There was no statistical support for an effect associated with the fitness-based quadratic selection gradient estimated for growth performance. Conditional on a performance measure, fitness-based directional selection gradients estimated for the leaf traits did not provide statistical support for direct effects of the focal traits on tree survival. This suggested that, under the environmental conditions of the trial site and time period covered in the current study, early-stage selection on the studied leaf traits may be mediated by their effects on growth performance, which in turn has a positive direct influence on later-age survival. We discuss the potential mechanistic basis of the direct effects of the focal leaf traits on tree growth, and the relevance of a putative causal pathway of trait effects on fitness through mediation by growth performance in the studied hot and dry environment.
Collapse
Affiliation(s)
- João Costa e Silva
- Centro de Estudos Florestais, Instituto Superior de Agronomia, Universidade de Lisboa, Lisboa, Portugal
| | - Brad M. Potts
- School of Natural Sciences, University of Tasmania, Hobart, TAS, Australia
- Australian Research Council (ARC) Training Centre for Forest Value, University of Tasmania, Hobart, TAS, Australia
| | - Georg Wiehl
- CSIRO Land and Water, Private Bag 5, Wembley, WA, Australia
| | | |
Collapse
|
41
|
Kirsch A, Kaproth MA. Defining plant ecological specialists and generalists: Building a framework for identification and classification. Ecol Evol 2022; 12:e9527. [DOI: 10.1002/ece3.9527] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2022] [Revised: 07/22/2022] [Accepted: 10/24/2022] [Indexed: 11/25/2022] Open
Affiliation(s)
- Alex Kirsch
- Department of Biological Sciences Minnesota State University, Mankato Mankato Minnesota USA
| | - Matthew A. Kaproth
- Department of Biological Sciences Minnesota State University, Mankato Mankato Minnesota USA
| |
Collapse
|
42
|
The Mutagenic Consequences of DNA Methylation within and across Generations. EPIGENOMES 2022; 6:epigenomes6040033. [PMID: 36278679 PMCID: PMC9624357 DOI: 10.3390/epigenomes6040033] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2022] [Revised: 09/20/2022] [Accepted: 09/28/2022] [Indexed: 12/28/2022] Open
Abstract
DNA methylation is an epigenetic modification with wide-ranging consequences across the life of an organism. This modification can be stable, persisting through development despite changing environmental conditions. However, in other contexts, DNA methylation can also be flexible, underlying organismal phenotypic plasticity. One underappreciated aspect of DNA methylation is that it is a potent mutagen; methylated cytosines mutate at a much faster rate than other genetic motifs. This mutagenic property of DNA methylation has been largely ignored in eco-evolutionary literature, despite its prevalence. Here, we explore how DNA methylation induced by environmental and other factors could promote mutation and lead to evolutionary change at a more rapid rate and in a more directed manner than through stochastic genetic mutations alone. We argue for future research on the evolutionary implications of DNA methylation driven mutations both within the lifetime of organisms, as well as across timescales.
Collapse
|
43
|
Morbey YE, Pauly D. Juvenile-to-adult transition invariances in fishes: Perspectives on proximate and ultimate causation. JOURNAL OF FISH BIOLOGY 2022; 101:874-884. [PMID: 35762307 DOI: 10.1111/jfb.15146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Accepted: 06/24/2022] [Indexed: 06/15/2023]
Abstract
To bridge physiological and evolutionary perspectives on size at maturity in fishes, the authors focus on the approximately invariant ratio between the estimated oxygen supply at size at maturity (Qm ) relative to that at asymptotic size (Q∞ ) among species within a taxonomic group, and show how two important theories related to this phenomenon complement each other. Gill-oxygen limitation theory proposes a mechanistic basis for a universal oxygen supply-based threshold for maturation, which applies among and within species. On the contrary, the authors show that a generalisation of life-history theory for the invariance of size at maturity (Lm ) relative to asymptotic size (L∞ ) can provide an evolutionary rationale for an oxygen-limited maturation threshold (Qm /Q∞ ). Extending previous inter- and intraspecific analyses, the authors show that maturation invariances also occur in lake whitefish Coregonus clupeaformis (Mitchill 1818), but at both scales, theory seems to underestimate the value of the maturation threshold. They highlight some key uncertainties in the model that should be addressed to help resolve the mismatch.
Collapse
Affiliation(s)
- Yolanda E Morbey
- Department of Biology, Western University, London, Ontario, Canada
| | - Daniel Pauly
- Institute for the Oceans and Fisheries, University of British Columbia, Vancouver, British Columbia, Canada
| |
Collapse
|
44
|
Type of Stress Induces Differential Responses in Acer rubrum (Red Maple), but Induced Responses Have No Effect on Herbivorous Pests. INTERNATIONAL JOURNAL OF PLANT BIOLOGY 2022. [DOI: 10.3390/ijpb13040033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Plants thrive in dynamic environments requiring adaptive strategies in response to environmental stressors. Furthermore, insect herbivores may be attracted or deterred by the expression of these traits. This study examines growth, physiological, and phytochemical adaptations of maple trees in response to stressors and how these stressors effect herbivore feeding behavior within an agricultural production system. Agricultural systems are unique because plants experience environmental stressors unique to production such as herbicide sprays and girdling. Using four environmental stressors commonly observed in agricultural production (control, mechanical defoliation, chemical defoliation, and girdling), applied to two cultivars of red maple (Acer rubrum, ‘Brandywine’ and ‘Franksred’), this study analyzed differentiation of expressed traits in a production system. Responses varied depending on cultivar and stress treatment but had no effect on insect herbivore behavior. Understanding the ecological interactions within these systems will provide information for better plant production and pest management recommendations.
Collapse
|
45
|
Giraldo‐Kalil LJ, Campo J, Paz H, Núñez‐Farfán J. Patterns of leaf trait variation underlie ecological differences among sympatric tree species of Damburneya in a tropical rainforest. AMERICAN JOURNAL OF BOTANY 2022; 109:1394-1409. [PMID: 36031775 PMCID: PMC9826457 DOI: 10.1002/ajb2.16056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 08/11/2022] [Accepted: 08/12/2022] [Indexed: 06/15/2023]
Abstract
PREMISE Although ecological differentiation driven by altitude and soil is hypothesized to promote coexistence of sympatric tree species of Damburneya (Lauraceae), the mechanistic role of leaf functional variation on ecological differentiation among co-occurring species remains unexplored. We aimed to determine whether the patterns of leaf trait variation reflect ecological differences among sympatric Damburneya species. We tested whether trait correlations underlying functional strategies and average species traits vary in response to local soil heterogeneity along an altitudinal gradient, potentially affecting species distributions. METHODS At two contrasting altitudes (100, 1100 m a.s.l.) in a Mexican tropical rainforest, we characterized soil chemical and physical properties and sampled four Damburneya species to quantify five leaf functional traits. We used linear models to analyze paired and multivariate trait correlations, spatial and interspecific effects on trait variation, and trait response to local soil heterogeneity. Relative contributions of intra- and interspecific variation to local trait variability were quantified with an ANOVA. RESULTS Soil nutrient availability was higher at low altitude, but all species had a high leaf N:P ratio across altitudes suggesting a limited P supply for plants. Species distribution differed altitudinally, with some species constrained to low or high altitude, potentially reflecting soil nutrient availability. Leaf traits responded to altitude and local soil properties, suggesting interspecific differences in functional strategies according to the leaf economics spectrum (conservative vs. acquisitive). CONCLUSIONS The interspecific divergence in functional strategies in response to local environmental conditions suggests that trait variation could underlie ecological differentiation among Damburneya sympatric species.
Collapse
Affiliation(s)
- Laura J. Giraldo‐Kalil
- Departamento de Ecología Evolutiva, Instituto de Ecología, Universidad Nacional Autónoma de México (UNAM)Ciudad de MéxicoMéxico
- Posgrado en Ciencias Biológicas, Unidad de Posgrado, Circuito de Posgrados, Universidad Nacional Autónoma de México (UNAM)Coyoacán, C. P. 04510, Ciudad de MéxicoMéxico
| | - Julio Campo
- Departamento de Ecología Funcional, Instituto de Ecología, Universidad Nacional Autónoma de México (UNAM)Ciudad de MéxicoMéxico
| | - Horacio Paz
- Instituto de Investigaciones en Ecosistemas y SustentabilidadUniversidad Nacional Autónoma de México (UNAM)MoreliaMéxico
| | - Juan Núñez‐Farfán
- Departamento de Ecología Evolutiva, Instituto de Ecología, Universidad Nacional Autónoma de México (UNAM)Ciudad de MéxicoMéxico
| |
Collapse
|
46
|
Blumstein M, Sala A, Weston DJ, Holbrook NM, Hopkins R. Plant carbohydrate storage: intra- and inter-specific trade-offs reveal a major life history trait. THE NEW PHYTOLOGIST 2022; 235:2211-2222. [PMID: 35524463 DOI: 10.1111/nph.18213] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 04/24/2022] [Indexed: 06/14/2023]
Abstract
Trade-offs among carbon sinks constrain how trees physiologically, ecologically, and evolutionarily respond to their environments. These trade-offs typically fall along a productive growth to conservative, bet-hedging continuum. How nonstructural carbohydrates (NSCs) stored in living tree cells (known as carbon stores) fit in this trade-off framework is not well understood. We examined relationships between growth and storage using both within species genetic variation from a common garden, and across species phenotypic variation from a global database. We demonstrate that storage is actively accumulated, as part of a conservative, bet-hedging life history strategy. Storage accumulates at the expense of growth both within and across species. Within the species Populus trichocarpa, genetic trade-offs show that for each additional unit of wood area growth (in cm2 yr-1 ) that genotypes invest in, they lose 1.2 to 1.7 units (mg g-1 NSC) of storage. Across species, for each additional unit of area growth (in cm2 yr-1 ), trees, on average, reduce their storage by 9.5% in stems and 10.4% in roots. Our findings impact our understanding of basic plant biology, fit storage into a widely used growth-survival trade-off spectrum describing life history strategy, and challenges the assumptions of passive storage made in ecosystem models today.
Collapse
Affiliation(s)
- Meghan Blumstein
- Department of Organismic and Evolutionary Biology, Harvard University, 26 Oxford St, Cambridge, MA, 02138, USA
- Civil and Environmental Engineering, Massachusetts Institute of Technology, 15 Vassar St, Cambridge, MA, 02139, USA
| | - Anna Sala
- Division of Biological Sciences, University of Montana, Missoula, MT, 59812, USA
| | - David J Weston
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Noel Michelle Holbrook
- Department of Organismic and Evolutionary Biology, Harvard University, 26 Oxford St, Cambridge, MA, 02138, USA
| | - Robin Hopkins
- Department of Organismic and Evolutionary Biology, Harvard University, 26 Oxford St, Cambridge, MA, 02138, USA
- The Arnold Arboretum, 1300 Centre St, Boston, MA, 02130, USA
| |
Collapse
|
47
|
Gomes Alves E, Taylor T, Robin M, Pinheiro Oliveira D, Schietti J, Duvoisin Júnior S, Zannoni N, Williams J, Hartmann C, Gonçalves JFC, Schöngart J, Wittmann F, Piedade MTF. Seasonal shifts in isoprenoid emission composition from three hyperdominant tree species in central Amazonia. PLANT BIOLOGY (STUTTGART, GERMANY) 2022; 24:721-733. [PMID: 35357064 DOI: 10.1111/plb.13419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Accepted: 03/08/2022] [Indexed: 06/14/2023]
Abstract
Volatile isoprenoids regulate plant performance and atmospheric processes, and Amazon forests comprise the dominant source to the global atmosphere. Still, there is a poor understanding of how isoprenoid emission capacities vary in response to ecophysiological and environmental controls in Amazonian ecosystems. We measured isoprenoid emission capacities of three Amazonian hyperdominant tree species - Protium hebetatum, Eschweilera grandiflora, Eschweilera coriacea - across seasons and along a topographic and edaphic environmental gradient in the central Amazon. From wet to dry season, both photosynthesis and isoprene emission capacities strongly declined, while emissions increased among the heavier isoprenoids: monoterpenes and sesquiterpenes. Plasticity across habitats was most evident in P. hebetatum, which emitted sesquiterpenes only in the dry season, at rates that significantly increased along the hydro-topographic gradient from white sands (shallow root water access) to uplands (deep water table). We suggest that emission composition shifts are part of a plastic response to increasing abiotic stress (e.g. heat and drought) and reduced photosynthetic supply of substrates for isoprenoid synthesis. Our comprehensive measurements suggest that more emphasis should be placed on other isoprenoids, besides isoprene, in the context of abiotic stress responses. Shifting emission compositions have implications for atmospheric responses because of the strong variation in reactivity among isoprenoid compounds.
Collapse
Affiliation(s)
- E Gomes Alves
- Department of Biogeochemical Processes, Max Planck Institute for Biogeochemistry, Jena, Germany
- Climate and Environment Department, National Institute of Amazonian Research, Manaus, Brazil
| | - T Taylor
- Biology Department, University of Miami, Coral Gables, FL, USA
- Department of Civil & Environmental Engineering, University of Michigan, Ann Arbor, MI, USA
| | - M Robin
- Department of Biogeochemical Processes, Max Planck Institute for Biogeochemistry, Jena, Germany
- Ecology Department, National Institute of Amazonian Research, Manaus, Brazil
| | - D Pinheiro Oliveira
- Climate and Environment Department, National Institute of Amazonian Research, Manaus, Brazil
| | - J Schietti
- Ecology Department, National Institute of Amazonian Research, Manaus, Brazil
- Biology Department, Federal University of Amazonas, Manaus, Brazil
| | | | - N Zannoni
- Atmospheric Chemistry Department, Max Planck Institute for Chemistry, Mainz, Germany
| | - J Williams
- Atmospheric Chemistry Department, Max Planck Institute for Chemistry, Mainz, Germany
| | - C Hartmann
- Atmospheric Chemistry Department, Max Planck Institute for Chemistry, Mainz, Germany
| | - J F C Gonçalves
- Coordination of Environmental Dynamics, National Institute of Amazonian Research, Manaus, Brazil
| | - J Schöngart
- Coordination of Environmental Dynamics, National Institute of Amazonian Research, Manaus, Brazil
| | - F Wittmann
- Department of Wetland Ecology, Karlsruhe Institute of Technology, Rastatt, Germany
| | - M T F Piedade
- Coordination of Environmental Dynamics, National Institute of Amazonian Research, Manaus, Brazil
| |
Collapse
|
48
|
Taff CC, Wingfield JC, Vitousek MN. The relative speed of the glucocorticoid stress response varies independently of scope and is predicted by environmental variability and longevity across birds. Horm Behav 2022; 144:105226. [PMID: 35863083 DOI: 10.1016/j.yhbeh.2022.105226] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 06/16/2022] [Accepted: 06/20/2022] [Indexed: 01/27/2023]
Abstract
The acute glucocorticoid response is a key mediator of the coordinated vertebrate response to unpredictable challenges. Rapid glucocorticoid increases initiate changes that allow animals to cope with stressors. The scope of the glucocorticoid response - defined here as the absolute increase in glucocorticoids - is associated with individual differences in performance and varies across species with environment and life history. In addition to varying in scope, responses can differ enormously in speed; however, relatively little is known about whether speed and absolute glucocorticoid levels covary, how selection shapes speed, or what aspects of speed are important. We used corticosterone samples collected at 5 time points from 1750 individuals of 60 species of birds to ask i) how the speed and scope of the glucocorticoid response covary and ii) whether variation in absolute or relative speed is predicted by environmental context or life history. Among species, faster absolute glucocorticoid responses were strongly associated with a larger scope. Despite this covariation, the relative speed of the glucocorticoid response (standardized within species) varied independently of absolute scope, suggesting that selection could operate on both features independently. Species with faster relative glucocorticoid responses lived in locations with more variable temperature and had shorter lifespans. Our results suggest that rapid changes associated with the speed of the glucocorticoid response, such as those occurring through non-genomic receptors, might be an important determinant of coping ability and we emphasize the need for studies designed to measure speed independently of absolute glucocorticoid levels.
Collapse
Affiliation(s)
- Conor C Taff
- Department of Ecology & Evolutionary Biology and Lab of Ornithology, Cornell University, United States of America.
| | - John C Wingfield
- Department of Neurobiology, Physiology, and Behavior, University of California-Davis, United States of America
| | - Maren N Vitousek
- Department of Ecology & Evolutionary Biology and Lab of Ornithology, Cornell University, United States of America
| |
Collapse
|
49
|
Soderberg DN, Bentz BJ, Runyon JB, Hood SM, Mock KE. Chemical defense strategies, induction timing, growth, and trade‐offs in
Pinus aristata
and
Pinus flexilis. Ecosphere 2022. [DOI: 10.1002/ecs2.4183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- David N. Soderberg
- Wildland Resources Department Utah State University Logan Utah USA
- Ecology Center Utah State University Logan Utah USA
| | - Barbara J. Bentz
- USDA Forest Service, Rocky Mountain Research Station Logan Utah USA
| | - Justin B. Runyon
- USDA Forest Service, Rocky Mountain Research Station Bozeman Montana USA
| | - Sharon M. Hood
- USDA Forest Service, Rocky Mountain Research Station Missoula Montana USA
| | - Karen E. Mock
- Wildland Resources Department Utah State University Logan Utah USA
- Ecology Center Utah State University Logan Utah USA
| |
Collapse
|
50
|
Croy JR, Pratt JD, Mooney KA. Latitudinal resource gradient shapes multivariate defense strategies in a long‐lived shrub. Ecology 2022; 103:e3830. [PMID: 35869688 PMCID: PMC10078560 DOI: 10.1002/ecy.3830] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Revised: 06/08/2022] [Accepted: 06/22/2022] [Indexed: 11/06/2022]
Abstract
Plant defense against herbivores is multidimensional, and investment into different defense traits is intertwined due to genetic, physiological, and ecological costs. This relationship is expected to generate a trade-off between direct defense and tolerance that is underlain by resource availability, with increasing resources being associated with increased investment in tolerance and decreased investment in direct resistance. We tested these predictions across populations of the shrub Artemisia californica by growing plants sourced from a latitudinal aridity gradient within common gardens located at the southern (xeric) and northern (mesic) portions of its distribution. We measured plant growth rate, resistance via a damage survey, and tolerance to herbivory by experimentally simulating vertebrate herbivory. Plants from more northern (vs. southern) environments were less resistant (received higher percent damage by vertebrate herbivores) and tended to be more tolerant (marginally significant) with respect to change in biomass measured 12 months after simulated vertebrate herbivory. Also, putative growth and defense traits paralleled patterns of resistance and tolerance, such that leaves from northern populations contained lower concentrations of terpenes and increased N, specific leaf area, and % water. Last, plant growth rate did not demonstrate clear clinal patterns, as northern populations (vs. southern populations) grew more slowly in the southern (xeric) garden, but there was no clinal relationship detected in the northern (mesic) garden. Overall, our findings support the prediction of lower resistance and higher tolerance in plant populations adapted to more resource-rich, mesic environments, but this trade-off was not associated with concomitant trade-offs in growth rate. These findings ultimately suggest that plant adaptation to resource availability and herbivory can shape intraspecific variation in multivariate plant defenses.
Collapse
Affiliation(s)
- Jordan R. Croy
- Department of Ecology and Evolutionary Biology University of California Irvine CA USA
- Department of Entomology University of Georgia Athens GA USA
| | - Jessica D. Pratt
- Department of Ecology and Evolutionary Biology University of California Irvine CA USA
| | - Kailen A. Mooney
- Department of Ecology and Evolutionary Biology University of California Irvine CA USA
| |
Collapse
|