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Feigs JT, Huang S, Holzhauer SIJ, Brunet J, Diekmann M, Hedwall P, Kramp K, Naaf T. Bumblebees mediate landscape effects on a forest herb's population genetic structure in European agricultural landscapes. Ecol Evol 2024; 14:e70078. [PMID: 39055773 PMCID: PMC11269766 DOI: 10.1002/ece3.70078] [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: 06/20/2024] [Revised: 07/08/2024] [Accepted: 07/11/2024] [Indexed: 07/27/2024] Open
Abstract
Spatially isolated plant populations in agricultural landscapes exhibit genetic responses not only to habitat fragmentation per se but also to the composition of the landscape matrix between habitat patches. These responses can only be understood by examining how the landscape matrix influences among-habitat movements of pollinators and seed vectors, which act as genetic linkers among populations. We studied the forest herb Polygonatum multiflorum and its associated pollinator and genetic linker, the bumblebee Bombus pascuorum, in three European agricultural landscapes. We aimed to identify which landscape features affect the movement activity of B. pascuorum between forest patches and to assess the relative importance of these features in explaining the forest herb's population genetic structure. We applied microsatellite markers to estimate the movement activity of the bumblebee as well as the population genetic structure of the forest herb. We modelled the movement activity as a function of various landscape metrics. Those metrics found to explain the movement activity best were then used to explain the population genetic structure of the forest herb. The bumblebee movement activity was affected by the cover of maize fields and semi-natural grasslands on a larger spatial scale and by landscape heterogeneity on a smaller spatial scale. For some measures of the forest herb's population genetic structure, that is, allelic richness, observed heterozygosity and the F-value, the combinations of landscape metrics, which explained the linker movement activity best, yielded lower AICc values than 95% of the models including all possible combinations of landscape metrics. Synthesis: The genetic linker, B. pascuorum, mediates landscape effects on the population genetic structure of the forest herb P. multiflorum. Our study indicates, that the movement of the genetic linker among forest patches, and thus the pollen driven gene flow of the herb, depends on the relative value of floral resources in the specific landscape setting. Noteworthy, the population genetic structure of the long-lived, clonal forest herb species correlated with recent land-use types such as maize, which have been existing for not more than a few decades within these landscapes. This underscores the short time in which land-use changes can influence the evolutionary potential of long-lived wild plants.
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Affiliation(s)
- Jannis Till Feigs
- Leibniz Centre for Agricultural Landscape Research (ZALF) e.VMünchebergGermany
| | - Siyu Huang
- Leibniz Centre for Agricultural Landscape Research (ZALF) e.VMünchebergGermany
| | - Stephanie I. J. Holzhauer
- Thünen Institute of Biodiversity, Johann Heinrich von Thünen Institute, Forestry and Fisheries, Federal Research Institute for Rural AreasBraunschweigGermany
| | - Jörg Brunet
- Southern Swedish Forest Research CentreSwedish University of Agricultural SciencesAlnarpSweden
| | - Martin Diekmann
- Vegetation Ecology and Conservation Biology, Institute of Ecology, FB 2University of BremenBremenGermany
| | - Per‐Ola Hedwall
- Southern Swedish Forest Research CentreSwedish University of Agricultural SciencesAlnarpSweden
| | - Katja Kramp
- Leibniz Centre for Agricultural Landscape Research (ZALF) e.VMünchebergGermany
| | - Tobias Naaf
- Leibniz Centre for Agricultural Landscape Research (ZALF) e.VMünchebergGermany
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2
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Aguiar LMS, Diniz UM, Bueno‐Rocha ID, Filomeno LRA, Aguiar‐Machado LS, Gomes PA, Togni PHB. Untangling biodiversity interactions: A meta network on pollination in Earth's most diverse tropical savanna. Ecol Evol 2024; 14:e11094. [PMID: 38476698 PMCID: PMC10928258 DOI: 10.1002/ece3.11094] [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: 09/19/2023] [Revised: 01/29/2024] [Accepted: 02/19/2024] [Indexed: 03/14/2024] Open
Abstract
Pollination is vital for ecosystem functioning, especially in biodiversity-rich regions like the Brazilian Cerrado. Our research establishes a comprehensive meta network of pollinator-plant interactions within this biome. We quantified the importance of different pollinator groups, identifying keystone species. We examined potential biases in sampling effort and the spatial behavior of interactions within the heterogeneous Cerrado plant physiognomies. Our investigation uncovered 1499 interactions among 293 plant species and 386 visitor species, with legitimate pollination accounting for 42.4% of the interactions. The network exhibited modularity, driven by bees and insects, with vertebrates bridging diurnal and nocturnal modules. While a generalized pattern emerged, high specialization existed within modules due to habitat diversity. Bees, particularly Apis mellifera (exotic) and Trigona spinipes (native), played central roles as network hubs. Hummingbirds and bats, engaged in specialized interactions showing strong connectivity within and between modules. Interestingly, invertebrate-vertebrate modules were more prevalent than expected in the meta network. However, a bias was evident, primarily within specific biogeographical districts with fragmented landscapes and intrusion from other biomes. Variations in plant species and endemism rates influenced pollinator occurrence and the Cerrado network topology. Our study offers valuable insights into pollinator-plant interactions within the Cerrado, encompassing both invertebrates and vertebrates. The modeled network represents a significant step in understanding the structural complexity of pollination networks, integrating partial networks from diverse pollination systems within heterogeneous habitats. Nevertheless, a biogeographical bias could limit a comprehensive understanding of network functionality across the Cerrado.
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Affiliation(s)
- Ludmilla M. S. Aguiar
- Departamento de Zoologia, Instituto de Ciências BiológicasUniversidade de BrasíliaBrasíliaDFBrazil
| | - Ugo M. Diniz
- Chair of Plant‐Insect Interactions, School of Life SciencesTechnical University of MunichFreisingGermany
| | - Igor D. Bueno‐Rocha
- Programa de Pós‐Graduação em Ecologia, Instituto de Ciências BiológicasUniversidade de BrasíliaBrasíliaDFBrazil
| | - Laura R. A. Filomeno
- Programa de Pós‐Graduação em Zoologia, Instituto de Ciências BiológicasUniversidade de BrasíliaBrasíliaDFBrazil
| | - Luísa S. Aguiar‐Machado
- Programa de Pós‐Graduação em Zoologia, Instituto de Ciências BiológicasUniversidade de BrasíliaBrasíliaDFBrazil
| | - Priscilla A. Gomes
- Programa de Pós‐Graduação em Zoologia, Instituto de Ciências BiológicasUniversidade de BrasíliaBrasíliaDFBrazil
| | - Pedro H. B. Togni
- Departamento de Ecologia, Instituto de Ciências BiológicasUniversidade de BrasíliaBrasíliaDFBrazil
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3
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Lewis EM, Fant JB, Moore MJ, Skogen KA. Hawkmoth and bee pollinators impact pollen dispersal at the landscape but not local scales in two species of Oenothera. AMERICAN JOURNAL OF BOTANY 2023:e16156. [PMID: 36934437 DOI: 10.1002/ajb2.16156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 02/01/2023] [Accepted: 02/01/2023] [Indexed: 06/18/2023]
Abstract
PREMISE Animal pollinators play an important role in pollen dispersal. Here, we assessed differences in pollen and seed dispersal and the role of pollinator functional groups with different foraging behaviors in generating patterns of genetic diversity over similar geographic ranges for two closely related taxa. We focused on two members of Oenothera section Calylophus (Onagraceae) that co-occur on gypsum outcrops throughout the northern Chihuahuan Desert but differ in floral phenotype and primary pollinator: Oenothera gayleana (bee) and O. hartwegii subsp. filifolia (hawkmoth). METHODS We measured breeding system and floral traits and studied gene flow and population differentiation at the local (<13 km; four populations) and landscape (60-440 km; five populations) scales using 10-11 nuclear (pollen dispersal) and three plastid (seed dispersal) microsatellite markers. RESULTS Both taxa were self-incompatible and floral traits were consistent with expectations for different pollinators. Seed and pollen dispersal patterns were distinctly different for both species. We found no evidence of genetic structure at the local scale but did at the landscape scale; O. gayleana showed greater differentiation and significant isolation by distance than in O. hartwegii subsp. filifolia. The plastid data were consistent with gravity dispersal of seeds and suggest that pollen dispersal is the principal driver of genetic structure in both species. CONCLUSIONS We demonstrated that pollinator functional groups can impact genetic differentiation in different and predictable ways. Hawkmoths, with larger foraging distances, can maintain gene flow across greater spatial scales than bees.
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Affiliation(s)
- Emily M Lewis
- Northwestern University, Program in Plant Biology and Conservation, Evanston, IL, 60201, USA
| | - Jeremie B Fant
- Northwestern University, Program in Plant Biology and Conservation, Evanston, IL, 60201, USA
- Negaunee Institute for Plant Conservation Science and Action, Chicago Botanic Garden, Glencoe, IL, 60022, USA
| | - Michael J Moore
- Biology Department, Oberlin College, Oberlin, OH, 44074, USA
| | - Krissa A Skogen
- Northwestern University, Program in Plant Biology and Conservation, Evanston, IL, 60201, USA
- Negaunee Institute for Plant Conservation Science and Action, Chicago Botanic Garden, Glencoe, IL, 60022, USA
- Department of Biological Sciences, Clemson University, Clemson, SC, 29634, USA
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4
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Donelan SC, Ogburn MB, Breitburg D. Legacy of past exposure to hypoxia and warming regulates an ecosystem service provided by oysters. GLOBAL CHANGE BIOLOGY 2023; 29:1328-1339. [PMID: 36541067 DOI: 10.1111/gcb.16571] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 12/07/2022] [Accepted: 12/08/2022] [Indexed: 05/26/2023]
Abstract
Climate change is having substantial impacts on organism fitness and ability to deliver critical ecosystem services, but these effects are often examined only in response to current environments. Past exposure to stress can also affect individuals via carryover effects, and whether these effects scale from individuals to influence ecosystem function and services is unknown. We explored within-generation carryover effects of two coastal climate change stressors-hypoxia and warming-on oyster (Crassostrea virginica) growth and nitrogen bioassimilation, an important ecosystem service. Oysters were exposed to a factorial combination of two temperature and two diel-cycling dissolved oxygen treatments at 3-months-old and again 1 year later. Carryover effects of hypoxia and warming influenced oyster growth and nitrogen storage in complex and context-dependent ways. When operating, carryover effects of single stressors generally reduced oyster nitrogen bioassimilation and relative investment in tissue versus shell growth, particularly in warm environments, while early life exposure to multiple stressors generally allowed oysters to perform as well as control oysters. When extrapolated to the reef scale, carryover effects decreased nitrogen stored by modeled oyster reefs in most conditions, with reductions as large as 41%, a substantial decline in a critical ecosystem service. In some scenarios, however, carryover effects increased nitrogen storage by modeled oyster reefs, again highlighting the complexity of these effects. Hence, even brief exposure to climate change stressors early in life may have persistent effects on an ecosystem service 1 year later. Our results show for the first time that within-generation carryover effects on individual phenotypes can impact processes at the ecosystem scale and may therefore be an overlooked factor determining ecosystem service delivery in response to anthropogenic change.
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Affiliation(s)
- Sarah C Donelan
- Smithsonian Environmental Research Center, Edgewater, Maryland, USA
| | - Matthew B Ogburn
- Smithsonian Environmental Research Center, Edgewater, Maryland, USA
| | - Denise Breitburg
- Smithsonian Environmental Research Center, Edgewater, Maryland, USA
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5
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Escobar S, Vigouroux Y, Karubian J, Zekraoui L, Balslev H, Montúfar R. Limited seed dispersal shapes fine‐scale spatial genetic structure in a Neotropical dioecious large‐seeded palm. Biotropica 2022. [DOI: 10.1111/btp.13172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Sebastián Escobar
- Ecoinformatics and Biodiversity, Department of Biology Aarhus University Aarhus Denmark
- Grupo de Investigación en Biodiversidad, Medio Ambiente, y Salud Universidad de Las Américas Quito Ecuador
| | - Yves Vigouroux
- Diversité, Adaptation, Développement des Plantes Institut de Recherche pour le Développement, University of Montpellier Montpellier France
| | - Jordan Karubian
- Department of Ecology and Evolutionary Biology Tulane University New Orleans USA
| | - Leila Zekraoui
- Diversité, Adaptation, Développement des Plantes Institut de Recherche pour le Développement, University of Montpellier Montpellier France
| | - Henrik Balslev
- Ecoinformatics and Biodiversity, Department of Biology Aarhus University Aarhus Denmark
| | - Rommel Montúfar
- Facultad de Ciencias Exactas y Naturales Pontificia Universidad Católica del Ecuador Quito Ecuador
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6
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Spatial isolation impacts pollinator visitation and reproductive success of a threatened self-incompatible Mediterranean tree. ACTA OECOLOGICA 2022. [DOI: 10.1016/j.actao.2022.103866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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7
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Jones FA, Hadley AS, Bonner K, Zahawi RA, Robinson WD, Kormann U, Betts MG. Elevated inbreeding in Heliconia tortuosa is determined by tropical forest stand age, isolation, and loss of hummingbird functional diversity. Mol Ecol 2022; 31:4465-4477. [PMID: 35808851 DOI: 10.1111/mec.16607] [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: 02/19/2021] [Revised: 06/10/2022] [Accepted: 06/29/2022] [Indexed: 11/27/2022]
Abstract
Forest conversion and habitat loss are major threats to biological diversity. Forest regeneration can mitigate the negative effects of old growth forest loss on species diversity, but less is known about the extent to which forest loss reduces genetic diversity in remnant populations and whether secondary forests play a role in the maintenance of genetic diversity. We quantified genetic diversity in a tropical hummingbird-pollinated understory herb, Heliconia tortuosa, across a landscape mosaic of primary and secondary forest regrowth. Using microsatellite genotypes from >850 adult and juvenile plants within 33 forest patches and extensive bird surveys, we examined the effect of contemporary and historical landscape features including forest age (primary vs. secondary forest), stand isolation, and pollinator assemblages on genetic diversity and levels of inbreeding in H. tortuosa. We found that inbreeding was up to 3x higher in secondary forest, and this effect was amplified with reductions in primary forest in the surrounding landscape through reduced observed heterozygosity in isolated fragments. Inbreeding in forest patches was negatively correlated with the local frequency of specialist long-distance foraging traplining hummingbirds. Traplining hummingbirds therefore appear to facilitate mating among unrelated plants - an inference we tested using empirically parameterized simulations. Higher levels of inbreeding in H. tortuosa are therefore associated with reduced functional diversity of hummingbirds in secondary forests and forest patches isolated from primary forests. Our findings suggest a cryptic consequence of primary forest loss and secondary forest regeneration through the disruption of mutualistic interactions resulting in the erosion of genetic diversity in a common understory plant.
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Affiliation(s)
- F Andrew Jones
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR, USA.,Smithsonian Tropical Research Institute, Panama City, Panama
| | - Adam S Hadley
- Forest Biodiversity Research Network, Forest Ecosystems and Society, Oregon State University, Corvallis, OR, USA
| | - Kaitlin Bonner
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR, USA.,Department of Biology, St. John Fisher College, Rochester, NY, USA
| | - Rakan A Zahawi
- School of Life Sciences and Lyon Arboretum, University of Hawai'i at Mānoa, Honolulu, HI, USA.,Charles Darwin Foundation, Puerto Ayora, Galapagos, Ecuador
| | - W Douglas Robinson
- Department of Fisheries and Wildlife, Oregon State University, Corvallis, OR, USA
| | - Urs Kormann
- Forest Biodiversity Research Network, Forest Ecosystems and Society, Oregon State University, Corvallis, OR, USA.,Division of Forest Sciences, School of Agricultural, Forest & Food Sciences, Bern University of Applied Sciences, Zollikofen, Switzerland.,Swiss Ornithological Institute, Sempach, Switzerland
| | - Matthew G Betts
- Forest Biodiversity Research Network, Forest Ecosystems and Society, Oregon State University, Corvallis, OR, USA
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8
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Dellinger AS, Paun O, Baar J, Temsch EM, Fernández-Fernández D, Schönenberger J. Population structure in Neotropical plants: integrating pollination biology, topography and climatic niches. Mol Ecol 2022; 31:2264-2280. [PMID: 35175652 PMCID: PMC9310734 DOI: 10.1111/mec.16403] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 02/10/2022] [Accepted: 02/11/2022] [Indexed: 11/29/2022]
Abstract
Animal pollinators mediate gene flow among plant populations, but in contrast to well‐studied topographic and (Pleistocene) environmental isolating barriers, their impact on population genetic differentiation remains largely unexplored. Comparing how these multifarious factors drive microevolutionary histories is, however, crucial for better resolving macroevolutionary patterns of plant diversification. Here we combined genomic analyses with landscape genetics and niche modelling across six related Neotropical plant species (424 individuals across 33 localities) differing in pollination strategy to test the hypothesis that highly mobile (vertebrate) pollinators more effectively link isolated localities than less mobile (bee) pollinators. We found consistently higher genetic differentiation (FST) among localities of bee‐ than vertebrate‐pollinated species with increasing geographical distance, topographic barriers and historical climatic instability. High admixture among montane populations further suggested relative climatic stability of Neotropical montane forests during the Pleistocene. Overall, our results indicate that pollinators may differentially impact the potential for allopatric speciation, thereby critically influencing diversification histories at macroevolutionary scales.
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Affiliation(s)
- Agnes S Dellinger
- Department of Botany and Biodiversity Research, University of Vienna, Austria.,Ecology and Evolutionary Biology, University of Colorado, Boulder, USA
| | - Ovidiu Paun
- Department of Botany and Biodiversity Research, University of Vienna, Austria
| | - Juliane Baar
- Department of Botany and Biodiversity Research, University of Vienna, Austria
| | - Eva M Temsch
- Department of Botany and Biodiversity Research, University of Vienna, Austria
| | | | - Jürg Schönenberger
- Department of Botany and Biodiversity Research, University of Vienna, Austria
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Leimberger KG, Dalsgaard B, Tobias JA, Wolf C, Betts MG. The evolution, ecology, and conservation of hummingbirds and their interactions with flowering plants. Biol Rev Camb Philos Soc 2022; 97:923-959. [PMID: 35029017 DOI: 10.1111/brv.12828] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 12/06/2021] [Accepted: 12/08/2021] [Indexed: 01/14/2023]
Abstract
The ecological co-dependency between plants and hummingbirds is a classic example of a mutualistic interaction: hummingbirds rely on floral nectar to fuel their rapid metabolisms, and more than 7000 plant species rely on hummingbirds for pollination. However, threats to hummingbirds are mounting, with 10% of 366 species considered globally threatened and 60% in decline. Despite the important ecological implications of these population declines, no recent review has examined plant-hummingbird interactions in the wider context of their evolution, ecology, and conservation. To provide this overview, we (i) assess the extent to which plants and hummingbirds have coevolved over millions of years, (ii) examine the mechanisms underlying plant-hummingbird interaction frequencies and hummingbird specialization, (iii) explore the factors driving the decline of hummingbird populations, and (iv) map out directions for future research and conservation. We find that, despite close associations between plants and hummingbirds, acquiring evidence for coevolution (versus one-sided adaptation) is difficult because data on fitness outcomes for both partners are required. Thus, linking plant-hummingbird interactions to plant reproduction is not only a major avenue for future coevolutionary work, but also for studies of interaction networks, which rarely incorporate pollinator effectiveness. Nevertheless, over the past decade, a growing body of literature on plant-hummingbird networks suggests that hummingbirds form relationships with plants primarily based on overlapping phenologies and trait-matching between bill length and flower length. On the other hand, species-level specialization appears to depend primarily on local community context, such as hummingbird abundance and nectar availability. Finally, although hummingbirds are commonly viewed as resilient opportunists that thrive in brushy habitats, we find that range size and forest dependency are key predictors of hummingbird extinction risk. A critical direction for future research is to examine how potential stressors - such as habitat loss and fragmentation, climate change, and introduction of non-native plants - may interact to affect hummingbirds and the plants they pollinate.
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Affiliation(s)
- Kara G Leimberger
- Forest Biodiversity Research Network, Department of Forest Ecosystems and Society, Oregon State University, 3100 SW Jefferson Way, Corvallis, OR, 97331, U.S.A
| | - Bo Dalsgaard
- Center for Macroecology, Evolution and Climate, GLOBE Institute, University of Copenhagen, Universitetsparken 15, Copenhagen Ø, 2100, Denmark
| | - Joseph A Tobias
- Department of Life Sciences, Imperial College London, Silwood Park, Buckhurst Road, Ascot, Berkshire, SL5 7PY, U.K
| | - Christopher Wolf
- Forest Biodiversity Research Network, Department of Forest Ecosystems and Society, Oregon State University, 3100 SW Jefferson Way, Corvallis, OR, 97331, U.S.A
| | - Matthew G Betts
- Forest Biodiversity Research Network, Department of Forest Ecosystems and Society, Oregon State University, 3100 SW Jefferson Way, Corvallis, OR, 97331, U.S.A
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10
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Vukeya LR, Mokotjomela TM, Malebo NJ, Oke S. Interspecific competition in germination of bird-dispersed seeds in a habitat with sparse tree vegetation in South Africa. BOTANICAL STUDIES 2021; 62:10. [PMID: 34110534 PMCID: PMC8192655 DOI: 10.1186/s40529-021-00317-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Accepted: 05/17/2021] [Indexed: 06/12/2023]
Abstract
BACKGROUND By transporting and scarifying the seeds during ingestion, avian frugivores reduce the competition with siblings, and may improve the germination which is critical for dispersal effectiveness and population recruitment. However, generally, there is limited knowledge on how deposited seeds interact/compete in the new microsite. We tested the hypothesis that the bird-dispersed seeds benefit from improved germination after their passage through the bird's gut; and we investigated the potential impact of seed density on competition at the microsites by determining whether seed density and species diversity influence germination in the Free State Province, South Africa. RESULTS Overall, the results partly supported the hypothesis. Germination trials with defecated seeds of five plant species compared with the manually depulped seeds showed that only Searsia lancea had significantly higher seed germination success and improved germination speed after passage through the bird gut while Ziziphus mucronata only benefited rapid germination. There was a significant correlation between seed size and the germination of bird-ingested seeds except in Olea subsp. africana possibly due to possession of extremely hard protective seed cover. Seed competition experiments pointed to Z. mucronata and O. subsp. africana having significant germination performance that was positively correlated to seed density and seed size while Ehretia rigida did not germinate at all. Seed species diversity in the germination trays did not have a significant impact since the seeds of two former plant species consistently displayed significantly higher germination across the competition levels. CONCLUSIONS We conclude that different plant species respond differently to seed ingestion by birds, and that further long-term tests for germination physiological responses of the seeds' samples used in this study are required since poor germination observed in other tree/shrub species cannot be attributed to competition solely.
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Affiliation(s)
- L R Vukeya
- South Africa National Biodiversity Institute, Free State National Botanical Garden, Free State, Rayton, Dan Pienaar, Danhof, P.O Box 29036, Bloemfontein, 9310, South Africa
- Faculty of Health and Environmental Science, Central University of Technology, Private Bag X20539, Bloemfontein, 9300, South Africa
| | - T M Mokotjomela
- Centre for Invasion Biology, South Africa National Biodiversity Institute, Free State National Botanical Garden, Free State, Rayton, Dan Pienaar, Danhof, P.O Box 29036, Bloemfontein, 9310, South Africa.
- School of Life Sciences, University of KwaZulu-Natal, P/Bag X01, Scottsville, Pietermaritzburg, 3209, South Africa.
| | - N J Malebo
- Faculty of Health and Environmental Science, Central University of Technology, Private Bag X20539, Bloemfontein, 9300, South Africa
| | - S Oke
- Faculty of Health and Environmental Science, Central University of Technology, Private Bag X20539, Bloemfontein, 9300, South Africa
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11
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Wessinger CA. From pollen dispersal to plant diversification: genetic consequences of pollination mode. THE NEW PHYTOLOGIST 2021; 229:3125-3132. [PMID: 33159813 DOI: 10.1111/nph.17073] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Accepted: 11/02/2020] [Indexed: 06/11/2023]
Abstract
Pollinators influence patterns of plant speciation, and one intuitive hypothesis is that pollinators affect rates of plant diversification through their effects on pollen dispersal. By specifying mating events and pollen flow across the landscape, distinct types of pollinators may cause different opportunities for allopatric speciation. This pollen dispersal-dependent speciation hypothesis predicts that pollination mode has effects on the spatial context of mating events that scale up to impact population structure and rates of species formation. Here I consider recent comparative studies, including genetic analyses of plant mating events, population structure and comparative phylogenetic analyses, to examine evidence for this model. These studies suggest that highly mobile pollinators conduct greater gene flow within and among populations, compared to less mobile pollinators. These differences influence patterns of population structure across the landscape. However, the effects of pollination mode on speciation rates is less predictable. In some contexts, the predicted effects of pollen dispersal are outweighed by other factors that govern speciation rates. A multiscale approach to examine effects of pollination mode on plant mating system, population structure and rates of diversification is key to determining the role of pollen dispersal on plant speciation for model clades.
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Affiliation(s)
- Carolyn A Wessinger
- Department of Biological Sciences, University of South Carolina, Columbia, SC, 27708, USA
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12
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Ballare KM, Jha S. Genetic structure across urban and agricultural landscapes reveals evidence of resource specialization and philopatry in the Eastern carpenter bee, Xylocopa virginica L. Evol Appl 2021; 14:136-149. [PMID: 33519961 PMCID: PMC7819568 DOI: 10.1111/eva.13078] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Revised: 05/27/2020] [Accepted: 07/06/2020] [Indexed: 01/03/2023] Open
Abstract
Human activity continues to impact global ecosystems, often by altering the habitat suitability, persistence, and movement of native species. It is thus critical to examine the population genetic structure of key ecosystemservice providers across human-altered landscapes to provide insight into the forces that limit wildlife persistence and movement across multiple spatial scales. While some studies have documented declines of bee pollinators as a result of human-mediated habitat alteration, others suggest that some bee species may benefit from altered land use due to increased food or nesting resource availability; however, detailed population and dispersal studies have been lacking. We investigated the population genetic structure of the Eastern carpenter bee, Xylocopa virginica, across 14 sites spanning more than 450 km, including dense urban areas and intensive agricultural habitat. X. virginica is a large bee which constructs nests in natural and human-associated wooden substrates, and is hypothesized to disperse broadly across urbanizing areas. Using 10 microsatellite loci, we detected significant genetic isolation by geographic distance and significant isolation by land use, where urban and cultivated landscapes were most conducive to gene flow. This is one of the first population genetic analyses to provide evidence of enhanced insect dispersal in human-altered areas as compared to semi-natural landscapes. We found moderate levels of regional-scale population structure across the study system (G'ST = 0.146) and substantial co-ancestry between the sampling regions, where co-ancestry patterns align with major human transportation corridors, suggesting that human-mediated movement may be influencing regional dispersal processes. Additionally, we found a signature of strong site-level philopatry where our analyses revealed significant levels of high genetic relatedness at very fine scales (<1 km), surprising given X. virginica's large body size. These results provide unique genetic evidence that insects can simultaneously exhibit substantial regional dispersal as well as high local nesting fidelity in landscapes dominated by human activity.
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Affiliation(s)
- Kimberly M. Ballare
- Department of Integrative BiologyBiological LaboratoriesThe University of Texas at AustinAustinTXUSA
- Department of Ecology and Evolutionary BiologyUniversity of California Santa CruzSanta CruzCAUSA
| | - Shalene Jha
- Department of Integrative BiologyBiological LaboratoriesThe University of Texas at AustinAustinTXUSA
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13
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Borges RC, Padovani K, Imperatriz-Fonseca VL, Giannini TC. A dataset of multi-functional ecological traits of Brazilian bees. Sci Data 2020; 7:120. [PMID: 32286316 PMCID: PMC7156730 DOI: 10.1038/s41597-020-0461-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 03/25/2020] [Indexed: 11/09/2022] Open
Abstract
Worldwide, bees are the most important group of animal pollinators. The ecosystem service they provide is vital in natural areas and croplands, and the taxonomic and functional diversity associated with bees is vital in understanding ecosystem functioning ensuring biodiversity conservation, food security and human livelihoods. A dataset of bees from mountainous areas of Carajás National Forest (eastern Amazon) and Nova Lima (Atlantic Forest) is presented here. It is a compilation of sampling efforts from 1983 to 2018 through the accession of data stored in museum collections. In total, 222 and 144 bee species were recorded in Carajás and Nova Lima, respectively. This represents the most robust dataset of Brazilian bees including species traits (body size, flight range, distribution, crop pollination, sociality and nesting) of 328 species. This dataset contributes to advances in the knowledge of the functional trait ecology of wild bees and can benefit further studies that analyze the response of wild bees to land use and climate changes, and its effects on the provision of crop pollination services.
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Affiliation(s)
- Rafael Cabral Borges
- Instituto Tecnológico Vale, Rua Boaventura da Silva 955, Belém, Pará, Brazil.
- Universidade Federal do Pará, Rua Augusto Correa 1, Belém, Pará, Brazil.
| | - Kleber Padovani
- Universidade Federal do Pará, Rua Augusto Correa 1, Belém, Pará, Brazil
| | | | - Tereza Cristina Giannini
- Instituto Tecnológico Vale, Rua Boaventura da Silva 955, Belém, Pará, Brazil
- Universidade Federal do Pará, Rua Augusto Correa 1, Belém, Pará, Brazil
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14
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Cristóbal-Pérez EJ, Fuchs EJ, Olivares-Pinto U, Quesada M. Janzen-Connell effects shape gene flow patterns and realized fitness in the tropical dioecious tree Spondias purpurea (ANACARDIACEAE). Sci Rep 2020; 10:4584. [PMID: 32165645 PMCID: PMC7067871 DOI: 10.1038/s41598-020-61394-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2019] [Accepted: 02/03/2020] [Indexed: 12/03/2022] Open
Abstract
Pollination and seed dispersal patterns determine gene flow within plant populations. In tropical forests, a high proportion of trees are dioecious, insect pollinated and dispersed by vertebrates. Dispersal vectors and density dependent factors may modulate realized gene flow and influence the magnitude of Fine Scale Genetic Structure (FSGS), affecting individual fitness. Spondias purpurea is a vertebrate-dispersed, insect-pollinated dioecious tropical tree. We assessed the influence of sex ratio, effective and realized gene flow on genetic diversity, FSGS and individual fitness within a 30 ha plot in the tropical dry forest reserve of Chamela-Cuixmala, Mexico. All individuals within the plot were tagged, geo-referenced and sampled for genetic analysis. We measured dbh and monitored sex expression during two reproductive seasons for all individuals. We collected seeds directly from maternal trees for effective pollen dispersal analysis, and analyzed established seedlings to assess realized pollen and seed dispersal. Nine microsatellite loci were used to describe genetic diversity parameters, FSGS and gene flow patterns among different size classes. A total of 354 individuals were located and classified into three size classes based on their dbh (<10, 10–20, and >20 cm). Population sex ratios were male biased and diametric size distributions differed among sexes, these differences may be the result of precocious male reproduction at early stages. Autocorrelation analyses indicate low FSGS (Fj <0.07) across all size classes. Long realized pollen and seed dispersal and differences among effective and realized gene flow were detected. In our study site low FSGS is associated with high gene flow levels. Effective and realized gene flow indicate a population recruitment curve indicating Janzen-Connell effects and suggesting fitness advantages for long-distance pollen and seed dispersal events.
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Affiliation(s)
- E Jacob Cristóbal-Pérez
- Instituto de Investigaciones en Ecosistemas y Sustentabilidad, Universidad Nacional Autónoma de México, Morelia, Michoacán, México.,Laboratorio Nacional de Análisis y Síntesis Ecológica, Escuela Nacional de Estudios Superiores Unidad Morelia, Universidad Nacional Autónoma de México, Morelia, Michoacán, México
| | - Eric J Fuchs
- Laboratorio Nacional de Análisis y Síntesis Ecológica, Escuela Nacional de Estudios Superiores Unidad Morelia, Universidad Nacional Autónoma de México, Morelia, Michoacán, México.,Escuela de Biología, Universidad de Costa Rica, San José, 11501-2060, Costa Rica
| | - Ulises Olivares-Pinto
- Laboratorio Nacional de Análisis y Síntesis Ecológica, Escuela Nacional de Estudios Superiores Unidad Morelia, Universidad Nacional Autónoma de México, Morelia, Michoacán, México.,Escuela Nacional de Estudios Superiores Unidad Juriquilla, Universidad Nacional Autónoma de México, Santiago de Querétaro, Querétaro, México
| | - Mauricio Quesada
- Instituto de Investigaciones en Ecosistemas y Sustentabilidad, Universidad Nacional Autónoma de México, Morelia, Michoacán, México. .,Laboratorio Nacional de Análisis y Síntesis Ecológica, Escuela Nacional de Estudios Superiores Unidad Morelia, Universidad Nacional Autónoma de México, Morelia, Michoacán, México.
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15
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Silva AR, Resende-Moreira LC, Carvalho CS, Lanes ECM, Ortiz-Vera MP, Viana PL, Jaffé R. Range-wide neutral and adaptive genetic structure of an endemic herb from Amazonian Savannas. AOB PLANTS 2020; 12:plaa003. [PMID: 32128104 PMCID: PMC7043808 DOI: 10.1093/aobpla/plaa003] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Accepted: 01/28/2020] [Indexed: 05/05/2023]
Abstract
Conserving genetic diversity in rare and narrowly distributed endemic species is essential to maintain their evolutionary potential and minimize extinction risk under future environmental change. In this study we assess neutral and adaptive genetic structure and genetic diversity in Brasilianthus carajensis (Melastomataceae), an endemic herb from Amazonian Savannas. Using RAD sequencing we identified a total of 9365 SNPs in 150 individuals collected across the species' entire distribution range. Relying on assumption-free genetic clustering methods and environmental association tests we then compared neutral with adaptive genetic structure. We found three neutral and six adaptive genetic clusters, which could be considered management units (MU) and adaptive units (AU), respectively. Pairwise genetic differentiation (F ST) ranged between 0.024 and 0.048, and even though effective population sizes were below 100, no significant inbreeding was found in any inferred cluster. Nearly 10 % of all analysed sequences contained loci associated with temperature and precipitation, from which only 25 sequences contained annotated proteins, with some of them being very relevant for physiological processes in plants. Our findings provide a detailed insight into genetic diversity, neutral and adaptive genetic structure in a rare endemic herb, which can help guide conservation and management actions to avoid the loss of unique genetic variation.
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Affiliation(s)
- Amanda R Silva
- Universidade Federal Rural da Amazônia/Museu Paraense Emílio Goeldi, Programa de Pós-graduação em Ciências Biológicas - Botânica Tropical, Belém-PA, Brazil
- Museu Paraense Emílio Goeldi, Programa de Capacitação Institucional (PCI), Belém-PA, Brazil
| | | | | | - Eder C M Lanes
- Instituto Tecnológico Vale, Desenvolvimento Sustentável, Belém-PA, Brazil
| | - Mabel P Ortiz-Vera
- Instituto Tecnológico Vale, Desenvolvimento Sustentável, Belém-PA, Brazil
- Universidade Federal do Pará, Instituto de Ciências Biológicas, Programa de Pós-Graduação em Genética e Biologia Molecular, Belém-PA, Brazil
| | - Pedro L Viana
- Universidade Federal Rural da Amazônia/Museu Paraense Emílio Goeldi, Programa de Pós-graduação em Ciências Biológicas - Botânica Tropical, Belém-PA, Brazil
| | - Rodolfo Jaffé
- Instituto Tecnológico Vale, Desenvolvimento Sustentável, Belém-PA, Brazil
- Universidade de São Paulo, Departamento de Ecologia, São Paulo-SP, Brazil
- Corresponding author’s email address:
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16
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Torres-Vanegas F, Hadley AS, Kormann UG, Jones FA, Betts MG, Wagner HH. The Landscape Genetic Signature of Pollination by Trapliners: Evidence From the Tropical Herb, Heliconia tortuosa. Front Genet 2019; 10:1206. [PMID: 31867039 PMCID: PMC6906188 DOI: 10.3389/fgene.2019.01206] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Accepted: 10/31/2019] [Indexed: 12/19/2022] Open
Abstract
Animal-mediated pollination is essential for the maintenance of plant reproduction, especially in tropical ecosystems, where pollination networks have been thought to have highly generalized structures. However, accumulating evidence suggests that not all floral visitors provide equally effective pollination services, potentially reducing the number of realized pollinators and increasing the cryptic specialization of pollination networks. Thus, there is a need to understand how different functional groups of pollinators influence pollination success. Here, we examined whether patterns of contemporary pollen-mediated gene flow in Heliconia tortuosa are consistent with the foraging strategy of its territorial or traplining hummingbird pollinators. Territorial hummingbirds defend clumps of flowers and are expected to transfer pollen locally. In contrast, traplining hummingbirds forage across longer distances, thereby increasing pollen flow among forest fragments, and are thought to repeatedly visit particular plants. If trapliners indeed visit the same plants repeatedly along their regular routes, this could lead to a situation where neighboring plants sample genetically distinct pollen pools. To test this hypothesis, we genotyped 720 seeds and 71 mother plants from 18 forest fragments at 11 microsatellite loci. We performed TwoGener analysis to test pollen pool differentiation within sites (among neighboring plants within the same forest fragment: ΦSC) and between sites (among forest fragments: ΦCT). We found strong, statistically significant pollen pool differentiation among neighboring mother plants (ΦSC = 0.0506), and weaker, statistically significant differentiation among sites (ΦCT = 0.0285). We interpret this pattern of hierarchical pollen pool differentiation as the landscape genetic signature of the foraging strategy of traplining hummingbirds, where repeatable, long-distance, and high-fidelity routes transfer pollen among particular plants. Although H. tortuosa is also visited by territorial hummingbirds, our results suggest that these pollinators do not contribute substantially to successful pollination, highlighting differences in realized pollination efficiency. This cryptic reduction in the number of realized pollinators potentially increases the vulnerability of pollination success to the decline of populations of traplining hummingbirds, which have been shown to be sensitive to forest fragmentation. We conclude that maintaining habitat connectivity to sustain the foraging routes of trapliners may be essential for the maintenance of pollen-mediated gene flow in human-modified landscapes.
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Affiliation(s)
- Felipe Torres-Vanegas
- Department of Ecology and Evolutionary Biology, University of Toronto, Mississauga, ON, Canada
| | - Adam S Hadley
- Department of Ecology and Evolutionary Biology, University of Toronto, Mississauga, ON, Canada.,Forest Biodiversity Research Network, Department of Forest Ecosystems and Society, Oregon State University, Corvallis, OR, United States
| | - Urs G Kormann
- Swiss Ornithological Institute, Sempach, Switzerland
| | - Frank Andrew Jones
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR, United States.,Smithsonian Tropical Research Institute, Panama, Panama
| | - Matthew G Betts
- Forest Biodiversity Research Network, Department of Forest Ecosystems and Society, Oregon State University, Corvallis, OR, United States
| | - Helene H Wagner
- Department of Ecology and Evolutionary Biology, University of Toronto, Mississauga, ON, Canada
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17
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Rebolleda Gómez M, Ashman T. Floral organs act as environmental filters and interact with pollinators to structure the yellow monkeyflower (
Mimulus guttatus
) floral microbiome. Mol Ecol 2019; 28:5155-5171. [DOI: 10.1111/mec.15280] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Revised: 10/10/2019] [Accepted: 10/14/2019] [Indexed: 12/18/2022]
Affiliation(s)
| | - Tia‐Lynn Ashman
- Department of Biological Sciences University of Pittsburgh Pittsburgh PA USA
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18
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Bezemer N, Hopper SD, Krauss SL, Phillips RD, Roberts DG. Primary pollinator exclusion has divergent consequences for pollen dispersal and mating in different populations of a bird‐pollinated tree. Mol Ecol 2019; 28:4883-4898. [DOI: 10.1111/mec.15264] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 09/23/2019] [Accepted: 09/30/2019] [Indexed: 01/09/2023]
Affiliation(s)
- Nicole Bezemer
- Centre of Excellence in Natural Resource Management School of Agriculture and Environment The University of Western Australia Albany WA Australia
- Department of Biodiversity Conservation and Attractions Kings Park Science West Perth WA Australia
| | - Stephen D. Hopper
- Centre of Excellence in Natural Resource Management School of Agriculture and Environment The University of Western Australia Albany WA Australia
| | - Siegy L. Krauss
- Department of Biodiversity Conservation and Attractions Kings Park Science West Perth WA Australia
- Biological Sciences The University of Western Australia Crawley WA Australia
| | - Ryan D. Phillips
- Department of Biodiversity Conservation and Attractions Kings Park Science West Perth WA Australia
- Department of Ecology, Environment and Evolution La Trobe University Melbourne Vic. Australia
| | - David G. Roberts
- Centre of Excellence in Natural Resource Management School of Agriculture and Environment The University of Western Australia Albany WA Australia
- Department of Biodiversity Conservation and Attractions Kings Park Science West Perth WA Australia
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19
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Grant EL, Conroy GC, Lamont RW, Reddell PW, Wallace HM, Ogbourne SM. Short distance pollen dispersal and low genetic diversity in a subcanopy tropical rainforest tree, Fontainea picrosperma (Euphorbiaceae). Heredity (Edinb) 2019; 123:503-516. [PMID: 31076650 PMCID: PMC6781113 DOI: 10.1038/s41437-019-0231-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 03/28/2019] [Accepted: 04/24/2019] [Indexed: 11/09/2022] Open
Abstract
Gene flow via pollen movement affects genetic variation in plant populations and is an important consideration in plant domestication. Fontainea picrosperma is a subcanopy rainforest tree that is of commercial interest because it is the source of tigilanol tiglate, a natural product used for the treatment of solid tumors. We identify patterns of pollen-mediated gene flow within natural populations of F. picrosperma and estimate genetic parameters and genetic structure between adult and juvenile groups using microsatellite markers. Our results show pollination events occur over much shorter distances than reported for tropical canopy species. At least 63% of seeds are sired by male trees located within 30 m of the mother. On average, 27% of the local male population contributed to successful reproduction of F. picrosperma with most fathers siring a single seed, however, the contributions to reproduction were uneven. Larger male trees with more flowers had greater reproductive success than those with less flowers (P < 0.05). There were comparatively low levels of genetic variation across the species (HE = 0.405 for adult trees and 0.379 for juveniles) and we found no loss of genetic diversity between adult and juvenile trees. Short distance pollen flow and low genetic diversity is theoretically a prelude to genetic impoverishment, however F. picrosperma has persisted through multiple significant climatic oscillations. Nevertheless, the remaining low genetic diversity is of concern for domestication programs which require maximal genetic diversity to facilitate efficient selective breeding and genetic improvement of this commercially significant species.
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Affiliation(s)
- Elektra L Grant
- GeneCology Research Centre, University of the Sunshine Coast, Sippy Downs, QLD, Australia
| | - Gabriel C Conroy
- GeneCology Research Centre, University of the Sunshine Coast, Sippy Downs, QLD, Australia
| | - Robert W Lamont
- GeneCology Research Centre, University of the Sunshine Coast, Sippy Downs, QLD, Australia
| | | | - Helen M Wallace
- GeneCology Research Centre, University of the Sunshine Coast, Sippy Downs, QLD, Australia
| | - Steven M Ogbourne
- GeneCology Research Centre, University of the Sunshine Coast, Sippy Downs, QLD, Australia.
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20
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Castilla AR, Garrote PJ, Żywiec M, Calvo G, Suárez-Esteban A, Delibes M, Godoy JA, Picó FX, Fedriani JM. Genetic rescue by distant trees mitigates qualitative pollen limitation imposed by fine-scale spatial genetic structure. Mol Ecol 2019; 28:4363-4374. [PMID: 31495974 DOI: 10.1111/mec.15233] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Revised: 07/17/2019] [Accepted: 07/22/2019] [Indexed: 11/26/2022]
Abstract
Restricted seed dispersal frequently leads to fine-scale spatial genetic structure (i.e., FSGS) within plant populations. Depending on its spatial extent and the mobility of pollinators, this inflated kinship at the immediate neighbourhood can critically impoverish pollen quality. Despite the common occurrence of positive FSGS within plant populations, our knowledge regarding the role of long-distance pollination preventing reproductive failure is still limited. Using microsatellite markers, we examined the existence of positive FSGS in two low-density populations of the tree Pyrus bourgaeana. We also designed controlled crosses among trees differing in their kinship to investigate the effects of increased local kinship on plant reproduction. We used six pollination treatments and fully monitored fruit production, fruit and seed weight, proportion of mature seeds per fruit, and seed germination. Our results revealed positive FSGS in both study populations and lower fruit initiation in flowers pollinated with pollen from highly-genetically related individuals within the neighbourhood, with this trend intensifying as the fruit development progressed. Besides, open-pollinated flowers exhibited lower performance compared to those pollinated by distant pollen donors, suggesting intense qualitative pollen limitation in natural populations. We found positive fine-scale spatial genetic structure is translated into impoverished pollen quality from nearby pollen donors which negatively impacts the reproductive success of trees in low-density populations. Under this scenario of intrapopulation genetic rescue by distant pollen donors, the relevance of highly-mobile pollinators for connecting spatially and genetically distant patches of trees may be crucial to safeguarding population recruitment.
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Affiliation(s)
- Antonio R Castilla
- Instituto Superior of Agronomy, Centre for Applied Ecology "Prof. Baeta Neves"/INBIO, University of Lisbon, Lisbon, Portugal.,Departamento de Ecología Integrativa, Estación Biológica de Doñana (EBD), Consejo Superior de Investigaciones Científicas (CSIC), Sevilla, Spain
| | - Pedro J Garrote
- Instituto Superior of Agronomy, Centre for Applied Ecology "Prof. Baeta Neves"/INBIO, University of Lisbon, Lisbon, Portugal.,Departamento de Biología de la Conservación, Estación Biológica de Doñana, Consejo Superior de Investigaciones Científicas (CSIC), Sevilla, Spain
| | - Magdalena Żywiec
- Instituto Superior of Agronomy, Centre for Applied Ecology "Prof. Baeta Neves"/INBIO, University of Lisbon, Lisbon, Portugal.,W. Szafer Institute of Botany, Polish Academy of Sciences, Krakow, Poland
| | - Gemma Calvo
- Departamento de Biología de la Conservación, Estación Biológica de Doñana, Consejo Superior de Investigaciones Científicas (CSIC), Sevilla, Spain
| | - Alberto Suárez-Esteban
- Departamento de Biología de la Conservación, Estación Biológica de Doñana, Consejo Superior de Investigaciones Científicas (CSIC), Sevilla, Spain
| | - Miguel Delibes
- Departamento de Biología de la Conservación, Estación Biológica de Doñana, Consejo Superior de Investigaciones Científicas (CSIC), Sevilla, Spain
| | - José A Godoy
- Departamento de Ecología Integrativa, Estación Biológica de Doñana (EBD), Consejo Superior de Investigaciones Científicas (CSIC), Sevilla, Spain
| | - F Xavier Picó
- Departamento de Ecología Integrativa, Estación Biológica de Doñana (EBD), Consejo Superior de Investigaciones Científicas (CSIC), Sevilla, Spain
| | - Jose M Fedriani
- Instituto Superior of Agronomy, Centre for Applied Ecology "Prof. Baeta Neves"/INBIO, University of Lisbon, Lisbon, Portugal.,Departamento de Biología de la Conservación, Estación Biológica de Doñana, Consejo Superior de Investigaciones Científicas (CSIC), Sevilla, Spain.,Centro de Investigaciones sobre Desertificación CIDE, CSIC-UVEG-GV, Moncada, Spain
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21
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Adhikari S, Burkle LA, O'Neill KM, Weaver DK, Delphia CM, Menalled FD. Dryland Organic Farming Partially Offsets Negative Effects of Highly Simplified Agricultural Landscapes on Forbs, Bees, and Bee-Flower Networks. ENVIRONMENTAL ENTOMOLOGY 2019; 48:826-835. [PMID: 31144714 DOI: 10.1093/ee/nvz056] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2018] [Indexed: 06/09/2023]
Abstract
Industrialized farming practices result in simplified agricultural landscapes, reduced biodiversity, and degraded species-interaction networks. Thus far, most research assessing the combined effects of farming systems and landscape complexity on beneficial insects has been conducted in relatively diversified and mesic systems and may not represent the large-scale, monoculture-based dryland agriculture that dominates many regions worldwide. Specifically, the effects of farming systems on forbs, bees, and their interactions are poorly understood in highly simplified dryland landscapes such as those in the Northern Great Plains, United States, an area globally important for conventional and organic small grain, pulse, forage, and oilseed production. During a 3-yr (2013-2015) study, we assessed 1) the effects of dryland no-till conventional and tilled organic farming on forbs, bees, and bee-flower networks and 2) the relationship between natural habitat and bee abundance. Flower density and richness were greater in tilled organic fields than in no-till conventional fields, and forb community composition differed between farming systems. We observed high bee diversity (109 taxa) in this highly simplified landscape, and bee abundance, richness, and community composition were similar between systems. Compared with tilled organic fields, bee-flower interactions in no-till conventional fields were poorly connected, suggesting these systems maintain relatively impoverished plant-pollinator networks. Natural habitat (11% of the landscape) did not affect small-bodied bee abundance in either farming system but positively affected large-bodied bees within 2,000 m of crop-field centers. In highly simplified agricultural landscapes, dryland organic farming and no-till conventional farming together support relatively high bee diversity, presumably because dryland organic farming enhances floral resources and bee-flower networks, and no-till management in conventional farming provides undisturbed ground-nesting habitats for wild bees (Hymenoptera: Apoidea).
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Affiliation(s)
- Subodh Adhikari
- Department of Land Resources and Environmental Sciences, Montana State University, Bozeman, MT
| | - Laura A Burkle
- Department of Ecology, Montana State University, Bozeman, MT
| | - Kevin M O'Neill
- Department of Land Resources and Environmental Sciences, Montana State University, Bozeman, MT
| | - David K Weaver
- Department of Land Resources and Environmental Sciences, Montana State University, Bozeman, MT
| | - Casey M Delphia
- Department of Land Resources and Environmental Sciences, Montana State University, Bozeman, MT
- Department of Ecology, Montana State University, Bozeman, MT
| | - Fabian D Menalled
- Department of Land Resources and Environmental Sciences, Montana State University, Bozeman, MT
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22
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Smith C, Weinman L, Gibbs J, Winfree R. Specialist foragers in forest bee communities are small, social or emerge early. J Anim Ecol 2019; 88:1158-1167. [PMID: 31063228 DOI: 10.1111/1365-2656.13003] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Accepted: 04/02/2019] [Indexed: 12/01/2022]
Abstract
Individual pollinators that specialize on one plant species within a foraging bout transfer more conspecific and less heterospecific pollen, positively affecting plant reproduction. However, we know much less about pollinator specialization at the scale of a foraging bout compared to specialization by pollinator species. In this study, we measured the diversity of pollen carried by individual bees foraging in forest plant communities in the mid-Atlantic United States. We found that individuals frequently carried low-diversity pollen loads, suggesting that specialization at the scale of the foraging bout is common. Individuals of solitary bee species carried higher diversity pollen loads than did individuals of social bee species; the latter have been better studied with respect to foraging bout specialization, but account for a small minority of the world's bee species. Bee body size was positively correlated with pollen load diversity, and individuals of polylectic (but not oligolectic) species carried increasingly diverse pollen loads as the season progressed, likely reflecting an increase in the diversity of flowers in bloom. Furthermore, the seasonal increase in pollen load diversity was stronger for bees visiting trees and shrubs than for bees visiting herbaceous plants. Overall, our results showed that both plant and pollinator species' traits as well as community-level patterns of flowering phenology are likely to be important determinants of individual-level interactions in plant-pollinator communities.
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Affiliation(s)
- Colleen Smith
- Graduate Program in Ecology & Evolution, Rutgers University, New Brunswick, New Jersey.,Department of Ecology, Evolution, and Natural Resources, Rutgers University, New Brunswick, New Jersey
| | - Lucia Weinman
- Graduate Program in Ecology & Evolution, Rutgers University, New Brunswick, New Jersey.,Department of Ecology, Evolution, and Natural Resources, Rutgers University, New Brunswick, New Jersey
| | - Jason Gibbs
- Department of Entomology, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Rachael Winfree
- Department of Ecology, Evolution, and Natural Resources, Rutgers University, New Brunswick, New Jersey
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23
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Aguilar R, Cristóbal‐Pérez EJ, Balvino‐Olvera FJ, Aguilar‐Aguilar M, Aguirre‐Acosta N, Ashworth L, Lobo JA, Martén‐Rodríguez S, Fuchs EJ, Sanchez‐Montoya G, Bernardello G, Quesada M. Habitat fragmentation reduces plant progeny quality: a global synthesis. Ecol Lett 2019; 22:1163-1173. [DOI: 10.1111/ele.13272] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Revised: 03/01/2019] [Accepted: 04/10/2019] [Indexed: 01/22/2023]
Affiliation(s)
- Ramiro Aguilar
- Instituto Multidisciplinario de Biología Vegetal Universidad Nacional de Córdoba –CONICET C.C. 495(X5000JJC)Córdoba Argentina
- Laboratorio Nacional de Análisis y Síntesis Ecológica (LANASE) Escuela Nacional de Estudios Superiores Unidad Morelia Universidad Nacional Autónoma de México Morelia Michoacán 58190 México
| | - Edson Jacob Cristóbal‐Pérez
- Laboratorio Nacional de Análisis y Síntesis Ecológica (LANASE) Escuela Nacional de Estudios Superiores Unidad Morelia Universidad Nacional Autónoma de México Morelia Michoacán 58190 México
- Instituto de Investigaciones en Ecosistemas y Sustentabilidad Universidad Nacional Autónoma de México Morelia Michoacán 58190 México
| | - Francisco Javier Balvino‐Olvera
- Laboratorio Nacional de Análisis y Síntesis Ecológica (LANASE) Escuela Nacional de Estudios Superiores Unidad Morelia Universidad Nacional Autónoma de México Morelia Michoacán 58190 México
- Instituto de Investigaciones en Ecosistemas y Sustentabilidad Universidad Nacional Autónoma de México Morelia Michoacán 58190 México
| | - María Aguilar‐Aguilar
- Laboratorio Nacional de Análisis y Síntesis Ecológica (LANASE) Escuela Nacional de Estudios Superiores Unidad Morelia Universidad Nacional Autónoma de México Morelia Michoacán 58190 México
- Instituto de Investigaciones en Ecosistemas y Sustentabilidad Universidad Nacional Autónoma de México Morelia Michoacán 58190 México
| | - Natalia Aguirre‐Acosta
- Instituto Multidisciplinario de Biología Vegetal Universidad Nacional de Córdoba –CONICET C.C. 495(X5000JJC)Córdoba Argentina
| | - Lorena Ashworth
- Instituto Multidisciplinario de Biología Vegetal Universidad Nacional de Córdoba –CONICET C.C. 495(X5000JJC)Córdoba Argentina
- Laboratorio Nacional de Análisis y Síntesis Ecológica (LANASE) Escuela Nacional de Estudios Superiores Unidad Morelia Universidad Nacional Autónoma de México Morelia Michoacán 58190 México
| | - Jorge A. Lobo
- Laboratorio Nacional de Análisis y Síntesis Ecológica (LANASE) Escuela Nacional de Estudios Superiores Unidad Morelia Universidad Nacional Autónoma de México Morelia Michoacán 58190 México
- Escuela de Biología Universidad de Costa Rica San Pedro2600 Costa Rica
| | - Silvana Martén‐Rodríguez
- Laboratorio Nacional de Análisis y Síntesis Ecológica (LANASE) Escuela Nacional de Estudios Superiores Unidad Morelia Universidad Nacional Autónoma de México Morelia Michoacán 58190 México
| | - Eric J. Fuchs
- Laboratorio Nacional de Análisis y Síntesis Ecológica (LANASE) Escuela Nacional de Estudios Superiores Unidad Morelia Universidad Nacional Autónoma de México Morelia Michoacán 58190 México
- Escuela de Biología Universidad de Costa Rica San Pedro2600 Costa Rica
| | - Gumersindo Sanchez‐Montoya
- Laboratorio Nacional de Análisis y Síntesis Ecológica (LANASE) Escuela Nacional de Estudios Superiores Unidad Morelia Universidad Nacional Autónoma de México Morelia Michoacán 58190 México
- Instituto de Investigaciones en Ecosistemas y Sustentabilidad Universidad Nacional Autónoma de México Morelia Michoacán 58190 México
| | - Gabriel Bernardello
- Instituto Multidisciplinario de Biología Vegetal Universidad Nacional de Córdoba –CONICET C.C. 495(X5000JJC)Córdoba Argentina
| | - Mauricio Quesada
- Laboratorio Nacional de Análisis y Síntesis Ecológica (LANASE) Escuela Nacional de Estudios Superiores Unidad Morelia Universidad Nacional Autónoma de México Morelia Michoacán 58190 México
- Instituto de Investigaciones en Ecosistemas y Sustentabilidad Universidad Nacional Autónoma de México Morelia Michoacán 58190 México
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24
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López-Uribe MM, Jha S, Soro A. A trait-based approach to predict population genetic structure in bees. Mol Ecol 2019; 28:1919-1929. [PMID: 30667117 DOI: 10.1111/mec.15028] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Accepted: 01/11/2019] [Indexed: 02/06/2023]
Abstract
Understanding population genetic structure is key to developing predictions about species susceptibility to environmental change, such as habitat fragmentation and climate change. It has been theorized that life-history traits may constrain some species in their dispersal and lead to greater signatures of population genetic structure. In this study, we use a quantitative comparative approach to assess if patterns of population genetic structure in bees are driven by three key species-level life-history traits: body size, sociality, and diet breadth. Specifically, we reviewed the current literature on bee population genetic structure, as measured by the differentiation indices Nei's GST, Hedrick's G'ST , and Jost's D. We then used phylogenetic generalised linear models to estimate the correlation between the evolution of these traits and patterns of genetic differentiation. Our analyses revealed a negative and significant effect of body size on genetic structure, regardless of differentiation index utilized. For Hedrick's G'ST and Jost's D, we also found a significant impact of sociality, where social species exhibited lower levels of differentiation than solitary species. We did not find an effect of diet specialization on population genetic structure. Overall, our results suggest that physical dispersal or other functions related to body size are among the most critical for mediating population structure for bees. We further highlight the importance of standardizing population genetic measures to more easily compare studies and to identify the most susceptible species to landscape and climatic changes.
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Affiliation(s)
- Margarita M López-Uribe
- Department of Entomology, Center for Pollinator Research, Pennsylvania State University, University Park, Pennsylvania
| | - Shalene Jha
- Deparment of Integrative Biology, The University of Texas at Austin, Austin, Texas
| | - Antonella Soro
- Institute for Biology, Martin-Luther University, Halle (Saale), Germany
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25
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Ballare KM, Neff JL, Ruppel R, Jha S. Multi-scalar drivers of biodiversity: local management mediates wild bee community response to regional urbanization. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2019; 29:e01869. [PMID: 30892745 DOI: 10.1002/eap.1869] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Revised: 11/13/2018] [Accepted: 12/19/2018] [Indexed: 06/09/2023]
Abstract
It is critical to understand the specific drivers of biodiversity across multiple spatial scales, especially within rapidly urbanizing areas, given the distinct management recommendations that may result at each scale. However, drivers of biodiversity patterns and interactions between drivers are often only measured and modeled at a single scale. In this study, we assessed bee community composition at three time periods in 20 grassland and 20 agriculture sites located across two major metroplexes. We examined how local environmental variables and surrounding landscape composition impact bee abundance, richness, and evenness, including comparisons between groups with different nesting strategies and body sizes. We collected nearly 13,000 specimens and identified 172 species. We found that levels of regional land use differentially impacted bee abundance and diversity depending on local habitat management. Specifically, within agriculture sites, bee richness was greater with increasing landscape-level seminatural habitat, while in grassland sites, bee richness was similar across landscapes regardless of seminatural habitat cover. Bee evenness at both site types declined with increasing landscape-level habitat heterogeneity, due to an increase of rare species at the grassland sites, but not in the agricultural sites, further indicating that diversity is driven by the interaction of local habitat quality and landscape-level habitat composition. We additionally found that agriculture sites supported higher abundances, but not richness, of small-bodied and below-ground nesting bees, while grassland sites supported higher abundances of aboveground nesting bees, and higher richness of large-bodied species. Increased levels of local bare ground were significantly related to multiple metrics of bee diversity, including greater belowground nesting bee abundance and richness. Local floral richness was also significantly related to increases of overall bee abundance, as well as the abundance and richness of small bees. Overall, we suggest that local land managers can support bee abundance and diversity by conserving areas of bare soil and promoting native floral diversity, the latter especially critical in highly urban agricultural spaces. Our results provide the first documentation of significant interactions between local habitat management and landscape composition impacting insect communities in urban systems, indicating that bee conservation practices depend critically on land use interactions across multiple spatial scales.
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Affiliation(s)
- Kimberly M Ballare
- Department of Integrative Biology, The University of Texas at Austin, 205 West 24th Street, 401 Biological Laboratories, Austin, Texas, 78712, USA
| | - John L Neff
- Central Texas Melittological Institute, 7307 Running Rope, Austin, Texas, 78731, USA
| | - Rebecca Ruppel
- Department of Integrative Biology, The University of Texas at Austin, 205 West 24th Street, 401 Biological Laboratories, Austin, Texas, 78712, USA
| | - Shalene Jha
- Department of Integrative Biology, The University of Texas at Austin, 205 West 24th Street, 401 Biological Laboratories, Austin, Texas, 78712, USA
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26
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O'Connell MC, Castilla AR, Lee LX, Jha S. Bee movement across heterogeneous tropical forests: multi‐paternal analyses reveal the importance of neighborhood composition for pollen dispersal. Biotropica 2018. [DOI: 10.1111/btp.12603] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Megan C. O'Connell
- Department of Integrative Biology University of Texas at Austin 1 University Station Austin TX 78712 USA
| | - Antonio R. Castilla
- Department of Integrative Biology University of Texas at Austin 1 University Station Austin TX 78712 USA
- Centro de Ecologia Aplicada Prof. Baeta Neves/InBIO Universidade de Lisboa Tapada da Ajuda 1349‐017 Lisbon Portugal
| | - Leticia X. Lee
- Department of Integrative Biology University of Texas at Austin 1 University Station Austin TX 78712 USA
- Department of Earth and Environment Boston University 685 Commonwealth Avenue Boston MA 02215 USA
| | - Shalene Jha
- Department of Integrative Biology University of Texas at Austin 1 University Station Austin TX 78712 USA
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27
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Santos JD, Varassin IG, Muschner VC. Effects of neighborhood on pollination and seed dispersal of a threatened palm. ACTA OECOLOGICA 2018. [DOI: 10.1016/j.actao.2018.08.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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28
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Cayuela H, Rougemont Q, Prunier JG, Moore JS, Clobert J, Besnard A, Bernatchez L. Demographic and genetic approaches to study dispersal in wild animal populations: A methodological review. Mol Ecol 2018; 27:3976-4010. [DOI: 10.1111/mec.14848] [Citation(s) in RCA: 85] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 08/17/2018] [Accepted: 08/19/2018] [Indexed: 12/31/2022]
Affiliation(s)
- Hugo Cayuela
- Institut de Biologie Intégrative et des Systèmes (IBIS); Université Laval; Québec City Québec Canada
| | - Quentin Rougemont
- Institut de Biologie Intégrative et des Systèmes (IBIS); Université Laval; Québec City Québec Canada
| | - Jérôme G. Prunier
- Station d'Ecologie Théorique et Expérimentale; Unité Mixte de Recherche (UMR) 5321; Centre National de la Recherche Scientifique (CNRS); Université Paul Sabatier (UPS); Moulis France
| | - Jean-Sébastien Moore
- Institut de Biologie Intégrative et des Systèmes (IBIS); Université Laval; Québec City Québec Canada
| | - Jean Clobert
- Station d'Ecologie Théorique et Expérimentale; Unité Mixte de Recherche (UMR) 5321; Centre National de la Recherche Scientifique (CNRS); Université Paul Sabatier (UPS); Moulis France
| | - Aurélien Besnard
- CNRS; PSL Research University; EPHE; UM, SupAgro, IRD; INRA; UMR 5175 CEFE; Montpellier France
| | - Louis Bernatchez
- Institut de Biologie Intégrative et des Systèmes (IBIS); Université Laval; Québec City Québec Canada
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