1
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Haque MT, Khan MK, Herberstein ME. Current evidence of climate-driven colour change in insects and its impact on sexual signals. Ecol Evol 2024; 14:e11623. [PMID: 38957695 PMCID: PMC11219098 DOI: 10.1002/ece3.11623] [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: 11/23/2023] [Revised: 06/03/2024] [Accepted: 06/11/2024] [Indexed: 07/04/2024] Open
Abstract
The colours of insects function in intraspecific communication such as sexual signalling, interspecific communication such as protection from predators, and in physiological processes, such as thermoregulation. The expression of melanin-based colours is temperature-dependent and thus likely to be impacted by a changing climate. However, it is unclear how climate change drives changes in body and wing colour may impact insect physiology and their interactions with conspecifics (e.g. mates) or heterospecific (e.g. predators or prey). The aim of this review is to synthesise the current knowledge of the consequences of climate-driven colour change on insects. Here, we discuss the environmental factors that affect insect colours, and then we outline the adaptive mechanisms in terms of phenotypic plasticity and microevolutionary response. Throughout we discuss the impact of climate-related colour change on insect physiology, and interactions with con-and-heterospecifics.
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Affiliation(s)
- Md Tangigul Haque
- School of Natural SciencesMacquarie UniversitySydneyNew South WalesAustralia
| | - Md Kawsar Khan
- School of Natural SciencesMacquarie UniversitySydneyNew South WalesAustralia
- Department of Biology, Chemistry and PharmacyFree University BerlinBerlinGermany
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2
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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.
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Affiliation(s)
- Andrew M. Stoehr
- Department of Biological SciencesButler UniversityIndianapolisIndianaUSA
| | - Katelyn Glaenzer
- Department of Biological SciencesButler UniversityIndianapolisIndianaUSA
| | - Devin VanWanzeele
- Department of Biological SciencesButler UniversityIndianapolisIndianaUSA
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3
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Usai G, Fambrini M, Pugliesi C, Simoni S. Exploring the patterns of evolution: Core thoughts and focus on the saltational model. Biosystems 2024; 238:105181. [PMID: 38479653 DOI: 10.1016/j.biosystems.2024.105181] [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: 12/07/2023] [Revised: 02/29/2024] [Accepted: 03/08/2024] [Indexed: 03/18/2024]
Abstract
The Modern Synthesis, a pillar in biological thought, united Darwin's species origin concepts with Mendel's laws of character heredity, providing a comprehensive understanding of evolution within species. Highlighting phenotypic variation and natural selection, it elucidated the environment's role as a selective force, shaping populations over time. This framework integrated additional mechanisms, including genetic drift, random mutations, and gene flow, predicting their cumulative effects on microevolution and the emergence of new species. Beyond the Modern Synthesis, the Extended Evolutionary Synthesis expands perspectives by recognizing the role of developmental plasticity, non-genetic inheritance, and epigenetics. We suggest that these aspects coexist in the plant evolutionary process; in this context, we focus on the saltational model, emphasizing how saltation events, such as dichotomous saltation, chromosomal mutations, epigenetic phenomena, and polyploidy, contribute to rapid evolutionary changes. The saltational model proposes that certain evolutionary changes, such as the rise of new species, may result suddenly from single macromutations rather than from gradual changes in DNA sequences and allele frequencies within a species over time. These events, observed in domesticated and wild higher plants, provide well-defined mechanistic bases, revealing their profound impact on plant diversity and rapid evolutionary events. Notably, next-generation sequencing exposes the likely crucial role of allopolyploidy and autopolyploidy (saltational events) in generating new plant species, each characterized by distinct chromosomal complements. In conclusion, through this review, we offer a thorough exploration of the ongoing dissertation on the saltational model, elucidating its implications for our understanding of plant evolutionary processes and paving the way for continued research in this intriguing field.
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Affiliation(s)
- Gabriele Usai
- Department of Agriculture, Food and Environment (DAFE), University of Pisa, Via del Borghetto 80, 56124, Pisa, Italy
| | - Marco Fambrini
- Department of Agriculture, Food and Environment (DAFE), University of Pisa, Via del Borghetto 80, 56124, Pisa, Italy
| | - Claudio Pugliesi
- Department of Agriculture, Food and Environment (DAFE), University of Pisa, Via del Borghetto 80, 56124, Pisa, Italy.
| | - Samuel Simoni
- Department of Agriculture, Food and Environment (DAFE), University of Pisa, Via del Borghetto 80, 56124, Pisa, Italy
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4
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Britton S, Davidowitz G. The adaptive role of melanin plasticity in thermally variable environments. J Evol Biol 2023; 36:1811-1821. [PMID: 37916691 DOI: 10.1111/jeb.14243] [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: 04/26/2023] [Revised: 09/16/2023] [Accepted: 09/21/2023] [Indexed: 11/03/2023]
Abstract
Understanding the evolution of adaptive plasticity is fundamental to our knowledge of how organisms interact with their environments and cope with environmental change. Plasticity in melanin pigmentation is common in response to variable environments, especially thermal environments. Yet, the adaptive significance of melanin plasticity in thermally variable environments is often assumed, but rarely explicitly tested. Furthermore, understanding the role of plasticity when a trait is responsive to multiple environmental stimuli and plays many functional roles remains poorly understood. We test the hypothesis that melanin plasticity is an adaptation for thermally variable environments using Hyles lineata, the white-lined sphinx moth, which shows plasticity in melanin pigmentation during the larval stage. Melanin pigmentation influences thermal traits in H. lineata, as melanic individuals had higher heating rates and reached higher body temperatures than non-melanic individuals. Importantly, melanin pigmentation has temperature specific fitness consequences. While melanic individuals had an advantage in cold temperatures, neither phenotype had a clear fitness advantage at warm temperatures. Thus, the costs associated with melanin production may be unrelated to thermal context. Our results highlight the importance of explicitly testing the adaptive role of plasticity and considering all the factors that influence costs and benefits of plastic phenotypes across environments.
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Affiliation(s)
- Sarah Britton
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, Arizona, USA
| | - Goggy Davidowitz
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, Arizona, USA
- Department of Entomology, University of Arizona, Tucson, Arizona, USA
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5
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Wood C, Do Linh San E, Parker DM. A Record of a Melanistic Rusty-Spotted Genet (Genetta maculata) from Lake Naivasha, Kenya. AFRICAN JOURNAL OF WILDLIFE RESEARCH 2022. [DOI: 10.3957/056.052.0099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Affiliation(s)
- Craig Wood
- Naivasha Yacht Club, Lotus Island, Kenya
| | - Emmanuel Do Linh San
- Department of Zoology and Entomology, University of Fort Hare, Alice, 5700 South Africa
| | - Dan M. Parker
- Wildlife and Reserve Management Research Group, Department of Zoology and Entomology, Rhodes University, Makhanda, 6140 South Africa
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6
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Chapuis M, Pélissié B, Piou C, Chardonnet F, Pagès C, Foucart A, Chapuis E, Jourdan‐Pineau H. Additive genetic variance for traits least related to fitness increases with environmental stress in the desert locust, Schistocerca gregaria. Ecol Evol 2021; 11:13930-13947. [PMID: 34707829 PMCID: PMC8525110 DOI: 10.1002/ece3.8099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 08/19/2021] [Accepted: 08/24/2021] [Indexed: 11/12/2022] Open
Abstract
Under environmental stress, previously hidden additive genetic variation can be unmasked and exposed to selection. The amount of hidden variation is expected to be higher for life history traits, which strongly correlate to individual fitness, than for morphological traits, in which fitness effects are more ambiguous. However, no consensual pattern has been recovered yet, and this idea is still debated in the literature. Here, we hypothesize that the classical categorization of traits (i.e., life history and morphology) may fail to capture their proximity to fitness. In the desert locust, Schistocerca gregaria, a model organism for the study of insect polyphenism, we quantified changes in additive genetic variation elicited by lifetime thermal stress for ten traits, in which evolutionary significance is known. Irrespective of their category, traits under strong stabilizing selection showed genetic invariance with environmental stress, while traits more loosely associated with fitness showed a marked increase in additive genetic variation in the stressful environment. Furthermore, traits involved in adaptive phenotypic plasticity (growth compensation) showed either no change in additive genetic variance or a change of moderate magnitude across thermal environments. We interpret this mitigated response of plastic traits in the context of integrated evolution to adjust the entire phenotype in heterogeneous environments (i.e., adaptiveness of initial plasticity, compromise of phenotypic compensation with stress, and shared developmental pathway). Altogether, our results indicate, in agreement with theoretical expectations, that environmental stress can increase available additive genetic variance in some desert locust traits, but those closely linked to fitness are largely unaffected. Our study also highlights the importance of assessing the proximity to fitness of a trait on a case-by-case basis and in an ecologically relevant context, as well as considering the processes of canalization and plasticity, involved in the control of phenotypic variation.
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Affiliation(s)
- Marie‐Pierre Chapuis
- CIRADCBGPMontpellierFrance
- CBGPCIRADMontpellier SupAgroINRAIRDUniv MontpellierMontpellierFrance
| | - Benjamin Pélissié
- CIRADCBGPMontpellierFrance
- CBGPCIRADMontpellier SupAgroINRAIRDUniv MontpellierMontpellierFrance
- Department of BiologyUniversity of Nebraska at KearneyKearneyNebraskaUSA
| | - Cyril Piou
- CIRADCBGPMontpellierFrance
- CBGPCIRADMontpellier SupAgroINRAIRDUniv MontpellierMontpellierFrance
| | - Floriane Chardonnet
- CIRADCBGPMontpellierFrance
- CBGPCIRADMontpellier SupAgroINRAIRDUniv MontpellierMontpellierFrance
| | | | - Antoine Foucart
- CIRADCBGPMontpellierFrance
- CBGPCIRADMontpellier SupAgroINRAIRDUniv MontpellierMontpellierFrance
| | - Elodie Chapuis
- MIVEGECUniversité de MontpellierCNRSIRDMontpellierFrance
- CIRADUMR PVBMTSaint‐PierreFrance
| | - Hélène Jourdan‐Pineau
- CIRADCBGPMontpellierFrance
- CBGPCIRADMontpellier SupAgroINRAIRDUniv MontpellierMontpellierFrance
- CIRADUMR PVBMTSaint‐PierreFrance
- CIRADUMR ASTREMontpellierFrance
- ASTREUniv MontpellierCIRADINRAMontpellierFrance
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7
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Tietgen L, Hagen IJ, Kleven O, Bernardi CD, Kvalnes T, Norén K, Hasselgren M, Wallén JF, Angerbjörn A, Landa A, Eide NE, Flagstad Ø, Jensen H. Fur colour in the Arctic fox: genetic architecture and consequences for fitness. Proc Biol Sci 2021; 288:20211452. [PMID: 34583587 PMCID: PMC8479361 DOI: 10.1098/rspb.2021.1452] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Genome-wide association studies provide good opportunities for studying the genetic basis of adaptive traits in wild populations. Yet, previous studies often failed to identify major effect genes. In this study, we used high-density single nucleotide polymorphism and individual fitness data from a wild non-model species. Using a whole-genome approach, we identified the MC1R gene as the sole causal gene underlying Arctic fox Vulpes lagopus fur colour. Further, we showed the adaptive importance of fur colour genotypes through measures of fitness that link ecological and evolutionary processes. We found a tendency for blue foxes that are heterozygous at the fur colour locus to have higher fitness than homozygous white foxes. The effect of genotype on fitness was independent of winter duration but varied with prey availability, with the strongest effect in years of increasing rodent populations. MC1R is located in a genomic region with high gene density, and we discuss the potential for indirect selection through linkage and pleiotropy. Our study shows that whole-genome analyses can be successfully applied to wild species and identify major effect genes underlying adaptive traits. Furthermore, we show how this approach can be used to identify knowledge gaps in our understanding of interactions between ecology and evolution.
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Affiliation(s)
- Lukas Tietgen
- Centre for Biodiversity Dynamics (CBD), Department of Biology, Norwegian University of Science and Technology (NTNU), Trondheim 7491, Norway.,Norwegian Institute for Nature Research (NINA), Trondheim 7485, Norway
| | - Ingerid J Hagen
- Centre for Biodiversity Dynamics (CBD), Department of Biology, Norwegian University of Science and Technology (NTNU), Trondheim 7491, Norway.,Norwegian Institute for Nature Research (NINA), Trondheim 7485, Norway
| | - Oddmund Kleven
- Norwegian Institute for Nature Research (NINA), Trondheim 7485, Norway
| | - Cecilia Di Bernardi
- Norwegian Institute for Nature Research (NINA), Trondheim 7485, Norway.,Department of Biology and Biotechnologies 'Charles Darwin', University of Rome La Sapienza, Viale dell' Università 32, Rome 00185, Italy
| | - Thomas Kvalnes
- Centre for Biodiversity Dynamics (CBD), Department of Biology, Norwegian University of Science and Technology (NTNU), Trondheim 7491, Norway
| | - Karin Norén
- Department of Zoology, Stockholm University, Stockholm 10691, Sweden
| | - Malin Hasselgren
- Department of Zoology, Stockholm University, Stockholm 10691, Sweden
| | - Johan Fredrik Wallén
- Department of Zoology, Stockholm University, Stockholm 10691, Sweden.,Swedish Museum of Natural History, Stockholm 10405, Sweden
| | - Anders Angerbjörn
- Department of Zoology, Stockholm University, Stockholm 10691, Sweden
| | - Arild Landa
- Norwegian Institute for Nature Research (NINA), Trondheim 7485, Norway
| | - Nina E Eide
- Norwegian Institute for Nature Research (NINA), Trondheim 7485, Norway
| | - Øystein Flagstad
- Norwegian Institute for Nature Research (NINA), Trondheim 7485, Norway
| | - Henrik Jensen
- Centre for Biodiversity Dynamics (CBD), Department of Biology, Norwegian University of Science and Technology (NTNU), Trondheim 7491, Norway
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8
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Punzalan D, Fang JT, Chen W, Rowe L. Divergence in life history and behaviour between hybridizing Phymata ambush bugs (Heteroptera: Reduviidae). Biol J Linn Soc Lond 2021. [DOI: 10.1093/biolinnean/blab006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Abstract
Life-history variation plays a central role in evolutionary and ecological processes and might be especially pertinent to divergence in closely related species. We investigated differences in life history in a pair of parapatric species of ambush bugs (Phymata) and a putative hybrid population. Despite the evidence of gene flow among these species, we found clear divergence between these parapatric populations for a suite of juvenile and adult life-history traits, including components of fitness. The higher latitude species was also less active, suggestive of potential divergence in dispersal. Increased melanism was correlated with longevity in one species, although it was unclear whether this relationship was causal. Observed differences in the life history between species were consistent with expectations of high-latitude species putting a premium on early or rapid development and increased reproductive rates. However, these results were not consistent with ‘pace-of-life syndromes’ at the species level. Individuals from the putative hybrid zone exhibited intermediate values for most traits, although they had slower development and reduced mobility, consistent with some previous work suggesting natural selection via hybrid breakdown.
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Affiliation(s)
- David Punzalan
- Department of Biology, University of Victoria, Victoria, BC, Canada
- Department of Ecology and Evolution, University of Toronto, Toronto, ON, Canada
| | - Julia T Fang
- Department of Ecology and Evolution, University of Toronto, Toronto, ON, Canada
| | - William Chen
- Department of Ecology and Evolution, University of Toronto, Toronto, ON, Canada
| | - Locke Rowe
- Department of Ecology and Evolution, University of Toronto, Toronto, ON, Canada
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9
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Di Bernardi C, Thierry AM, Eide NE, Bowler DE, Rød-Eriksen L, Blumentrath S, Tietgen L, Sandercock BK, Flagstad Ø, Landa A. Fitness and fur colouration: Testing the camouflage and thermoregulation hypotheses in an Arctic mammal. J Anim Ecol 2021; 90:1328-1340. [PMID: 33660289 DOI: 10.1111/1365-2656.13457] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Accepted: 01/16/2021] [Indexed: 01/28/2023]
Abstract
Selection for crypsis has been recognized as an important ecological driver of animal colouration, whereas the relative importance of thermoregulation is more contentious with mixed empirical support. A potential thermal advantage of darker individuals has been observed in a wide range of animal species. Arctic animals that exhibit colour polymorphisms and undergo seasonal colour moults are interesting study subjects for testing the two alternative hypotheses: demographic performance of different colour morphs might be differentially affected by snow cover with a cryptic advantage for lighter morphs, or conversely by winter temperature with a thermal advantage for darker morphs. In this study, we explored whether camouflage and thermoregulation might explain differences in reproduction and survival between the white and blue colour morphs of the Arctic fox Vulpes lagopus under natural conditions. Juvenile and adult survival, breeding propensity and litter size were measured for 798 captive-bred and released or wild-born Arctic foxes monitored during an 11-year period (2007-2017) in two subpopulations in south-central Norway. We investigated the proportion of the two colour morphs and compared their demographic performance in relation to spatial variation in duration of snow cover, onset of snow season and winter temperatures. After population re-establishment, a higher proportion of blue individuals was observed among wild-born Arctic foxes compared to the proportion of blue foxes released from the captive population. Our field study provides the first evidence for an effect of colour morph on the reproductive performance of Arctic foxes under natural conditions, with a higher breeding propensity of the blue morph compared to the white one. Performance of the two colour morphs was not differentially affected by the climatic variables, except for juvenile survival. Blue morph juveniles showed a tendency for higher survival under colder winter temperatures but lower survival under warmer temperatures compared to white morph juveniles. Overall, our findings do not consistently support predictions of the camouflage or the thermoregulation hypotheses. The higher success of blue foxes suggests an advantage of the dark morph not directly related to disruptive selection by crypsis or thermoregulation. Our results rather point to physiological adaptations and behavioural traits not necessarily connected to thermoregulation, such as stress response, immune function, sexual behaviour and aggressiveness. Our findings highlight the need to explore the potential role of genetic linkage or pleiotropy in influencing the fitness of white and blue Arctic foxes as well as other species with colour polymorphisms.
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Affiliation(s)
| | | | - Nina E Eide
- Norwegian Institute for Nature Research (NINA), Trondheim, Norway
| | - Diana E Bowler
- Norwegian Institute for Nature Research (NINA), Trondheim, Norway.,German Centre for Integrative Biodiversity Research (iDiv), Halle-Jena-Leipzig, Germany.,Institute of Biodiversity, Friedrich Schiller University Jena, Jena, Germany
| | - Lars Rød-Eriksen
- Norwegian Institute for Nature Research (NINA), Trondheim, Norway
| | | | - Lukas Tietgen
- Norwegian Institute for Nature Research (NINA), Trondheim, Norway.,Centre for Biodiversity Dynamics (CBD), Department of Biology, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
| | | | - Øystein Flagstad
- Norwegian Institute for Nature Research (NINA), Trondheim, Norway
| | - Arild Landa
- Norwegian Institute for Nature Research (NINA), Bergen, Norway
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10
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Tougeron K, van Baaren J, Town J, Nordin D, Dumonceaux T, Wist T. Body-color plasticity of the English grain aphid in response to light in both laboratory and field conditions. Evol Ecol 2020. [DOI: 10.1007/s10682-020-10088-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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11
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Clusella-Trullas S, Nielsen M. The evolution of insect body coloration under changing climates. CURRENT OPINION IN INSECT SCIENCE 2020; 41:25-32. [PMID: 32629405 DOI: 10.1016/j.cois.2020.05.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 05/13/2020] [Accepted: 05/19/2020] [Indexed: 06/11/2023]
Abstract
Insects have been influential models in research on color variation, its evolutionary drivers and the mechanistic basis of such variation. More recently, several studies have indicated that insect color is responding to rapid climate change. However, it remains challenging to ascertain drivers of color variation among populations and species, and across space and time, as multiple biotic and abiotic factors can interact and mediate color change. Here, we describe some of the challenges and recent advances made in this field. First, we outline the main alternative hypotheses that exist for insect color variation in relation to climatic factors. Second, we review the existing evidence for contemporary adaptive evolution of insect color in response to climate change and then discuss factors that can promote or hinder the evolution of color in response to climate change. Finally, we propose future directions and highlight gaps in this research field. Pigments and structures producing insect color can vary concurrently or independently, and may evolve at different rates, with poorly understood effects on gene frequencies and fitness. Disentangling multiple competing hypotheses explaining insect coloration should be key to assign color variation as an evolutionary response to climate change.
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Affiliation(s)
- Susana Clusella-Trullas
- Centre for Invasion Biology, Dept. of Botany and Zoology, Stellenbosch University, Stellenbosch, South Africa.
| | - Matthew Nielsen
- Department of Zoology, Stockholm University, Stockholm, Sweden
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12
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Pinkert S, Friess N, Zeuss D, Gossner MM, Brandl R, Brunzel S. Mobility costs and energy uptake mediate the effects of morphological traits on species' distribution and abundance. Ecology 2020; 101:e03121. [PMID: 33460060 DOI: 10.1002/ecy.3121] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2019] [Revised: 04/21/2020] [Accepted: 05/06/2020] [Indexed: 11/05/2022]
Abstract
Individuals of large or dark-colored ectothermic species often have a higher reproduction and activity than small or light-colored ones. However, investments into body size or darker colors should negatively affect the fitness of individuals as they increase their growth and maintenance costs. Thus, it is unlikely that morphological traits directly affect species' distribution and abundance. Yet, this simplification is frequently made in trait-based ecological analyses. Here, we integrated the energy allocation strategies of species into an ecophysiological framework to explore the mechanisms that link species' morphological traits and population dynamics. We hypothesized that the effects of morphological traits on species' distribution and abundance are not direct but mediated by components of the energy budget and that species can allocate more energy towards dispersal and reproduction if they compensate their energetic costs by reducing mobility costs or increasing energy uptake. To classify species' energy allocation strategies, we used easily measured proxies for the mobility costs and energy uptake of butterflies that can be also applied to other taxa. We demonstrated that contrasting effects of morphological traits on distribution and abundance of butterfly species offset each other when species' energy allocation strategies are not taken into account. Larger and darker butterfly species had wider distributions and were more abundant if they compensated the investment into body size and color darkness (i.e., melanin) by reducing their mobility costs or increasing energy uptake. Adults of darker species were more mobile and foraged less compared to lighter colored ones, if an investment into melanin was indirectly compensated via a size-dependent reduction of mobility costs or increase of energy uptake. Our results indicate that differences in the energy allocations strategies of species account for a considerable part of the variation in species' distribution and abundance that is left unexplained by morphological traits alone and ignoring these differences can lead to false mechanistic conclusions. Therefore, our findings highlight the potential of integrating proxies for species' energy allocation strategies into trait-based models not only for understanding the physiological mechanisms underlying variation in species' distribution and abundance, but also for improving predictions of the population dynamics of species.
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Affiliation(s)
- Stefan Pinkert
- Faculty of Biology, Animal Ecology, Philipps-University Marburg, Marburg, 35043, Germany.,Faculty of Landscape Architecture, Biodiversity and Conservation, University of Applied Sciences Erfurt, Erfurt, 99085, Germany
| | - Nicolas Friess
- Faculty of Geography, Environmental Informatics, Philipps-University Marburg, Marburg, 35043, Germany
| | - Dirk Zeuss
- Faculty of Geography, Environmental Informatics, Philipps-University Marburg, Marburg, 35043, Germany
| | - Martin M Gossner
- Forest Entomology, Swiss Federal Research Institute WSL, Birmensdorf, 8903, Switzerland
| | - Roland Brandl
- Faculty of Biology, Animal Ecology, Philipps-University Marburg, Marburg, 35043, Germany
| | - Stefan Brunzel
- Faculty of Landscape Architecture, Biodiversity and Conservation, University of Applied Sciences Erfurt, Erfurt, 99085, Germany
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13
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Scriber JM. Assessing ecological and physiological costs of melanism in North American Papilio glaucus females: two decades of dark morph frequency declines. INSECT SCIENCE 2020; 27:583-612. [PMID: 30456932 PMCID: PMC7277061 DOI: 10.1111/1744-7917.12653] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Revised: 09/11/2018] [Accepted: 09/17/2018] [Indexed: 06/09/2023]
Abstract
Polymorphisms for melanic form of insects may provide various selective advantages. However, melanic alleles may have significant/subtle pleiotrophic "costs." Several potential pleiotrophic effects of the W (=Y)-linked melanism gene in Papilio glaucus L. (Lepidoptera) showed no costs for melanic versus yellow in adult size, oviposition preferences, fecundity, egg viability, larval survival/growth rates, cold stress tolerance, or postdiapause emergence times. Sexual selection (males choosing yellow rather than mimetic dark females) had been suggested to provide a balanced polymorphism in P. glaucus, but spermatophore counts in wild females and direct field tethering studies of size-matched pairs of virgin females (dark and yellow), show that male preferences are random or frequency-dependent from Florida to Michigan, providing no yellow counter-advantages. Recent frequency declines of dark (melanic/mimetic) females in P. glaucus populations are shown in several major populations from Florida (27.3°N latitude) to Ohio (38.5° N). Summer temperatures have increased significantly at all these locations during this time (1999-2018), but whether dark morphs may be more vulnerable (in any stage) to such climate warming remains to be determined. Additional potential reasons for the frequency declines in mimetic females are discussed: (i) genetic introgression of Z-linked melanism suppressor genes from P. canadensis (R & J) and the hybrid species, P. appalachiensis (Pavulaan & Wright), (ii) differential developmental incompatibilities, or Haldane effects, known to occur in hybrids, (iii) selection against intermediately melanic ("dusty") females (with the W-linked melanic gene, b+) which higher temperatures can cause.
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Affiliation(s)
- J. Mark Scriber
- Department of EntomologyMichigan State UniversityEast LansingMichiganUSA
- McGuire Center for Lepidoptera and BiodiversityFlorida Museum of Natural HistoryUniversity of FloridaGainesvilleFloridaUSA
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14
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Rádai Z, Kiss J, Babczyńska A, Kardos G, Báthori F, Samu F, Barta Z. Consequences of rapid development owing to cohort splitting: just how costly is it to hurry? J Exp Biol 2020; 223:jeb219659. [PMID: 32098878 DOI: 10.1242/jeb.219659] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Accepted: 02/11/2020] [Indexed: 12/27/2022]
Abstract
In cohort splitting, diverging sub-cohorts may show substantial differences in their growth and developmental rates. Although in the past, causes and adaptive value of cohort splitting were studied in detail, individual-level consequences of cohort splitting are still rather overlooked. Life history theory predicts that considerably increased growth and developmental rates should be traded off against other costly life history traits. However, it is not clear whether one should expect such associations in adaptive developmental plasticity scenarios, because natural selection might have promoted genotypes that mitigate those potential costs of rapid development. To address these contrasting propositions, we assessed life history traits in the wolf spider Pardosa agrestis, both collected from natural habitat and reared in laboratory. We found that some traits are negatively associated with developmental rates in spiders collected from the wild, but these associations were relaxed to a considerable extent in laboratory-reared specimens. In general, we observed no consistent trend for the presence of developmental costs, although some results might suggest higher relative fecundity costs in rapidly developing females. Our study provides a detailed approach to the understanding of individual-level consequences of cohort splitting, and to the associations between key life history traits in adaptive developmental plasticity scenarios.
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Affiliation(s)
- Zoltán Rádai
- MTA-DE Behavioural Ecology Research Group, Department of Evolutionary Zoology, University of Debrecen, H-4032 Debrecen, Hungary
| | - Johanna Kiss
- MTA-DE Behavioural Ecology Research Group, Department of Evolutionary Zoology, University of Debrecen, H-4032 Debrecen, Hungary
| | - Agnieszka Babczyńska
- Department of Animal Physiology and Ecotoxicology, University of Silesia in Katowice, 40-007 Katowice, Poland
| | - Gábor Kardos
- Department of Medical Microbiology, Medical and Health Science Center, University of Debrecen, H-4032 Debrecen, Hungary
| | - Ferenc Báthori
- Department of Ecology, University of Debrecen, H-4032 Debrecen, Hungary
| | - Ferenc Samu
- Plant Protection Institute, Centre for Agricultural Research, Hungarian Academy of Sciences, H-1029 Budapest, Hungary
| | - Zoltán Barta
- MTA-DE Behavioural Ecology Research Group, Department of Evolutionary Zoology, University of Debrecen, H-4032 Debrecen, Hungary
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15
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Nattero J, Carbajal de la Fuente AL, Piccinali RV, Cardozo M, Rodríguez CS, Crocco LB. Characterization of melanic and non-melanic forms in domestic and peridomestic populations of Triatoma infestans (Hemiptera: Reduviidae). Parasit Vectors 2020; 13:47. [PMID: 32014037 PMCID: PMC6998255 DOI: 10.1186/s13071-020-3912-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Accepted: 01/21/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Melanic (dark) morphs have been barely reported in peridomestic and sylvatic conditions for Triatoma infestans, the most important vector of Chagas disease in the Southern Cone of South America. Adults with dark and small yellow markings on the connexivum were collected after manual searches conducted by technical personnel in 62 domiciliary units in Cruz del Eje, Córdoba Province, Argentina. The last community-wide insecticide spraying campaign before the study had been conducted three years earlier. We investigated if there was a measurable color morph variation (melanic and non-melanic) in wings and connexivum; we determined infestation, distribution of melanic and non-melanic forms, and correspondence of colorimetric variation with variations in morphology (wing size and shape and body length), development (wing fluctuating asymmetry), physiology (nutritional status) or behaviour (flight initiation). RESULTS Forty-nine females, 54 males and 217 nymphs were collected in 24 domiciliary units. House infestation and colonization were 53% and 47%, respectively. Most of the T. infestans individuals (83.2%) were collected in chicken coops; intradomicile infestation was recorded in only one case. The chromatic cluster analysis showed two well-defined groups: melanic and non-melanic. The melanic group included 17 (35%) females and 25 (46%) males. Peridomestic infestation was lower for melanic than for non-melanic adults. Melanic morphs were collected in houses from several localities. Sexual dimorphisms were confirmed by morphometric measurements. Body length was large in melanic adults (P < 0.01 only for males). Differences between groups were significant for wing size and shape, but not for weight or weight/body length ratio. Melanic females and males showed significantly higher fluctuating asymmetry (FA) indices than their non-melanic counterparts. CONCLUSIONS This is the second report of melanic forms of T. infestans in domestic and peridomestic habitats in the Dry Chaco region of Argentina. Although non-melanic adults exhibited a higher infestation rate, melanic adults were widespread in the area and were collected in the infested domicile and in most types of peridomestic annexes. Differences in morphometric variables between groups might be due to different ecological adaptations. The higher FA levels observed in melanic individuals suggest a higher developmental instability and a selective advantage of non-melanic individuals in domestic and peridomestic habitats.
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Affiliation(s)
- Julieta Nattero
- Departamento de Ecología, Genética y Evolución/Laboratorio de Eco-Epidemiología, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina. .,Instituto de Ecología, Genética y Evolución (CONICET-IEGEBA), CONICET-Universidad de Buenos Aires, Buenos Aires, Argentina.
| | - Ana Laura Carbajal de la Fuente
- Departamento de Ecología, Genética y Evolución/Laboratorio de Eco-Epidemiología, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina.,Instituto de Ecología, Genética y Evolución (CONICET-IEGEBA), CONICET-Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Romina Valeria Piccinali
- Departamento de Ecología, Genética y Evolución/Laboratorio de Eco-Epidemiología, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina.,Instituto de Ecología, Genética y Evolución (CONICET-IEGEBA), CONICET-Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Miriam Cardozo
- Cátedra de Introducción a la Biología, Facultad de Ciencias Exactas, Físicas y Naturales, Universidad Nacional de Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas (IIBYT-CONICET), Avda. Vélez Sarsfield 299, piso 5, X5000JJC, Córdoba, Argentina
| | - Claudia Susana Rodríguez
- Cátedra de Introducción a la Biología, Facultad de Ciencias Exactas, Físicas y Naturales, Universidad Nacional de Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas (IIBYT-CONICET), Avda. Vélez Sarsfield 299, piso 5, X5000JJC, Córdoba, Argentina
| | - Liliana Beatriz Crocco
- Cátedra de Introducción a la Biología, Facultad de Ciencias Exactas, Físicas y Naturales, Universidad Nacional de Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas (IIBYT-CONICET), Avda. Vélez Sarsfield 299, piso 5, X5000JJC, Córdoba, Argentina
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16
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Raffard A, Therry L, Finn F, Koch K, Brodin T, Blanchet S, Cote J. Does range expansion modify trait covariation? A study of a northward expanding dragonfly. Oecologia 2020; 192:565-575. [PMID: 31932924 DOI: 10.1007/s00442-020-04592-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2017] [Accepted: 01/02/2020] [Indexed: 10/25/2022]
Abstract
The adaptive value of correlations among phenotypic traits depends on the prevailing environmental conditions. Differences in selection pressures during species range expansions may therefore shape phenotypic integration. In this study, we assessed variation in behavioral and morphological traits, as well as their covariations, in replicated southern and northern European populations of the northward expanding dragonfly Crocothemis erythraea. Larvae from northern populations were, on average, darker in color, and therefore, better camouflaged than larvae from southern populations. However, there was no difference in activity level. Darkness and activity were positively correlated in larvae from northern populations, whereas this trait covariation was missing in southern populations. This suggests the emergence of alternative strategies in time-limited northern populations, a higher activity level that required better camouflage through darker coloration, while less active larvae benefited from an energy-saving strategy by reducing the investment in costly traits, such as body darkness. We further found that larger larvae emerged into larger adults, with a higher investment in flight morphology. Our findings imply that phenotypic integration is associated with the northward range shift, potentially differentially shaping fitness consequences, and ecological interactions in southern versus northern populations.
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Affiliation(s)
- Allan Raffard
- Centre Nationale Pour la Recherche Scientifique (CNRS), Université Paul Sabatier (UPS), Station d'Écologie Théorique et Expérimentale, UMR 5321, 09200, Moulis, France.
| | - Lieven Therry
- Centre Nationale Pour la Recherche Scientifique (CNRS), Université Paul Sabatier (UPS), Station d'Écologie Théorique et Expérimentale, UMR 5321, 09200, Moulis, France
| | - Fia Finn
- Centre Nationale Pour la Recherche Scientifique (CNRS), Université Paul Sabatier (UPS), Station d'Écologie Théorique et Expérimentale, UMR 5321, 09200, Moulis, France.,Department of Aquaculture and Fish Biology, Hólar University College, Háeyri 1, IS-550, Sauðárkrókur, Iceland.,Institute of Life and Environmental Science, University of Iceland, Sturlugata 7, IS-101, Reykjavík, Iceland
| | - Kamilla Koch
- Department of Evolutionary Ecology, Johannes Gutenberg-University Mainz, 55131, Mainz, Germany
| | - Tomas Brodin
- Department of Ecology and Environmental Science, Umeå University, 90187, Umeå, Sweden
| | - Simon Blanchet
- Centre Nationale Pour la Recherche Scientifique (CNRS), Université Paul Sabatier (UPS), Station d'Écologie Théorique et Expérimentale, UMR 5321, 09200, Moulis, France.,CNRS, UPS, IRD, Laboratoire Évolution et Diversité Biologique, UMR 5174, 31062, Cedex 9, Toulouse, France
| | - Julien Cote
- CNRS, UPS, IRD, Laboratoire Évolution et Diversité Biologique, UMR 5174, 31062, Cedex 9, Toulouse, France
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17
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Svensson EI, Willink B, Duryea MC, Lancaster LT. Temperature drives pre‐reproductive selection and shapes the biogeography of a female polymorphism. Ecol Lett 2019; 23:149-159. [DOI: 10.1111/ele.13417] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Accepted: 10/09/2019] [Indexed: 01/03/2023]
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18
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Ehrlich RL, Zuk M. The role of sex and temperature in melanin-based immune function. CAN J ZOOL 2019. [DOI: 10.1139/cjz-2018-0323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Sex differences in immunity have been observed across a wide range of species. Still, it remains unclear how sex-specific interactions with the environment are linked to sex differences in immunity. We studied the plasticity of immunological sex differences by focusing on melanin-based traits in the Pacific field cricket (Teleogryllus oceanicus (Le Guillou, 1841)). Insects rely on the pigment melanin for both immune function and coloration of the cuticle; therefore, changes in melanin production for one of these traits may indirectly affect the other. Male crickets use melanized wing structures to chirp. These cuticular structures are missing in females and a songless male morph. Given that the thermal environment influences cuticle melanization, we investigated the interactive effects of sex and developmental temperature on melanin-based immunity. Both immunity and wing cuticle melanism were reduced in individuals that developed under warmer temperatures. Rearing temperature also mediated the extent to which the sexes differed in immune traits. Males had darker cuticles, whereas females expressed greater immune activity, suggesting that sex-specific investment in melanin corresponds with sex differences in immunity. However, the lack of immunological differences between the two male morphs does not support the hypothesis that investment in cuticle melanism affects investment in immunity.
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Affiliation(s)
- Rebecca L. Ehrlich
- Department of Ecology, Evolution, and Behavior, University of Minnesota-Twin Cities, 1987 Upper Buford Circle, St. Paul, MN 55108, USA
- Department of Ecology, Evolution, and Behavior, University of Minnesota-Twin Cities, 1987 Upper Buford Circle, St. Paul, MN 55108, USA
| | - Marlene Zuk
- Department of Ecology, Evolution, and Behavior, University of Minnesota-Twin Cities, 1987 Upper Buford Circle, St. Paul, MN 55108, USA
- Department of Ecology, Evolution, and Behavior, University of Minnesota-Twin Cities, 1987 Upper Buford Circle, St. Paul, MN 55108, USA
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19
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Zvereva EL, Hunter MD, Zverev V, Kruglova OY, Kozlov MV. Climate warming leads to decline in frequencies of melanic individuals in subarctic leaf beetle populations. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 673:237-244. [PMID: 30991315 DOI: 10.1016/j.scitotenv.2019.03.458] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Revised: 03/29/2019] [Accepted: 03/29/2019] [Indexed: 06/09/2023]
Abstract
Intraspecific diversity buffers populations from deleterious impacts of environmental change. Nevertheless, the consequences of climate warming for phenotypic and genetic diversity within populations and species remain poorly understood. The goal of our study was to explore among-year variations in the phenotypic structure of populations and their relationships with climate variability and population dynamics. We analysed multiyear (1992-2018) data on colour morph frequencies within populations of the leaf beetle, Chrysomela lapponica, from multiple sites in the Kola Peninsula (northwestern Russia). We observed a strong decline in the proportion of dark (melanic) morphs among overwintered beetles during the study period; this decline was consistent across all study sites. Using model selection procedures, we explained declines in the dark morph of overwintered beetles by increases in minimum spring (May-June) daily temperatures. Other climatic characteristics, pollution load, and beetle population density were unrelated to variation in colour morph frequencies. Among newly emerged beetles (August), dark morph frequencies also decreased with an increase in average spring temperatures, but were unrelated to mean temperatures during the larval development period (July). These results suggest that the two-fold decline in dark morph frequencies during the past 26 years has been driven by the 2.5 °C increase in spring temperatures, most likely because dark males lose the mating advantages over light males that they obtain during cold springs. The continued loss of dark morphs and related decrease in within-population diversity may render leaf beetle populations more vulnerable to future environmental changes, in particular to those expressed in extreme weather fluctuations. Our study demonstrates that declines in within-population diversity are already underway in subarctic areas, and that these declines are likely driven by climate warming.
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Affiliation(s)
- Elena L Zvereva
- Department of Biology, University of Turku, Turku 20014, Finland.
| | - Mark D Hunter
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI 48109-1048, USA
| | - Vitali Zverev
- Department of Biology, University of Turku, Turku 20014, Finland
| | | | - Mikhail V Kozlov
- Department of Biology, University of Turku, Turku 20014, Finland
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20
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Briolat ES, Burdfield‐Steel ER, Paul SC, Rönkä KH, Seymoure BM, Stankowich T, Stuckert AMM. Diversity in warning coloration: selective paradox or the norm? Biol Rev Camb Philos Soc 2019; 94:388-414. [PMID: 30152037 PMCID: PMC6446817 DOI: 10.1111/brv.12460] [Citation(s) in RCA: 68] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Revised: 07/25/2018] [Accepted: 07/27/2018] [Indexed: 01/03/2023]
Abstract
Aposematic theory has historically predicted that predators should select for warning signals to converge on a single form, as a result of frequency-dependent learning. However, widespread variation in warning signals is observed across closely related species, populations and, most problematically for evolutionary biologists, among individuals in the same population. Recent research has yielded an increased awareness of this diversity, challenging the paradigm of signal monomorphy in aposematic animals. Here we provide a comprehensive synthesis of these disparate lines of investigation, identifying within them three broad classes of explanation for variation in aposematic warning signals: genetic mechanisms, differences among predators and predator behaviour, and alternative selection pressures upon the signal. The mechanisms producing warning coloration are also important. Detailed studies of the genetic basis of warning signals in some species, most notably Heliconius butterflies, are beginning to shed light on the genetic architecture facilitating or limiting key processes such as the evolution and maintenance of polymorphisms, hybridisation, and speciation. Work on predator behaviour is changing our perception of the predator community as a single homogenous selective agent, emphasising the dynamic nature of predator-prey interactions. Predator variability in a range of factors (e.g. perceptual abilities, tolerance to chemical defences, and individual motivation), suggests that the role of predators is more complicated than previously appreciated. With complex selection regimes at work, polytypisms and polymorphisms may even occur in Müllerian mimicry systems. Meanwhile, phenotypes are often multifunctional, and thus subject to additional biotic and abiotic selection pressures. Some of these selective pressures, primarily sexual selection and thermoregulation, have received considerable attention, while others, such as disease risk and parental effects, offer promising avenues to explore. As well as reviewing the existing evidence from both empirical studies and theoretical modelling, we highlight hypotheses that could benefit from further investigation in aposematic species. Finally by collating known instances of variation in warning signals, we provide a valuable resource for understanding the taxonomic spread of diversity in aposematic signalling and with which to direct future research. A greater appreciation of the extent of variation in aposematic species, and of the selective pressures and constraints which contribute to this once-paradoxical phenomenon, yields a new perspective for the field of aposematic signalling.
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Affiliation(s)
- Emmanuelle S. Briolat
- Centre for Ecology & Conservation, College of Life & Environmental SciencesUniversity of ExeterPenryn Campus, Penryn, Cornwall, TR10 9FEU.K.
| | - Emily R. Burdfield‐Steel
- Centre of Excellence in Biological Interactions, Department of Biological and Environmental ScienceUniversity of JyväskyläJyväskylä, 40014Finland
| | - Sarah C. Paul
- Centre for Ecology & Conservation, College of Life & Environmental SciencesUniversity of ExeterPenryn Campus, Penryn, Cornwall, TR10 9FEU.K.
- Department of Chemical EcologyBielefeld UniversityUniversitätsstraße 25, 33615, BielefeldGermany
| | - Katja H. Rönkä
- Centre of Excellence in Biological Interactions, Department of Biological and Environmental ScienceUniversity of JyväskyläJyväskylä, 40014Finland
- Organismal and Evolutionary Biology Research Programme, Faculty of Biological and Environmental SciencesUniversity of HelsinkiHelsinki, 00014Finland
| | - Brett M. Seymoure
- Department of BiologyColorado State UniversityFort CollinsCO 80525U.S.A.
- Department of Fish, Wildlife, and Conservation BiologyColorado State UniversityFort CollinsCO 80525U.S.A.
| | - Theodore Stankowich
- Department of Biological SciencesCalifornia State UniversityLong BeachCA 90840U.S.A.
| | - Adam M. M. Stuckert
- Department of BiologyEast Carolina University1000 E Fifth St, GreenvilleNC 27858U.S.A.
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21
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Sandre SL, Kaart T, Morehouse N, Tammaru T. Weak and inconsistent associations between melanic darkness and fitness-related traits in an insect. J Evol Biol 2018; 31:1959-1968. [PMID: 30311708 DOI: 10.1111/jeb.13387] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Accepted: 10/08/2018] [Indexed: 01/16/2023]
Abstract
The idea that the fitness value of body coloration may be affected by biochemically mediated trade-offs has received much research attention. For example, melanization is believed to interact with other fitness-related traits via competition for substrates, costs associated with the synthesis of melanin or pleiotropic effects of the involved genes. However, genetic correlations between coloration and fitness-related traits remain poorly understood. Here, we present a quantitative-genetic study of a coloration trait correlated to melanin-based cuticular darkness ('darkness', hereafter) in a geometrid moth, Ematurga atomaria. This species has considerable variation in larval appearance. We focus on correlations between larval darkness and fitness-related growth performance traits. Both a half-sib analysis and an 'animal model' approach revealed moderately high heritabilities of larval darkness and indices of growth performance. Heritability estimates of darkness derived from the animal model were, however, considerably higher than those based on the half-sib model suggesting that the determination of coloration includes genetic interactions and epigenetic effects. Importantly, on the host plant with the largest sample size, we found no evidence for either genetic or environmental correlations between darkness and growth parameters. On an alternative host plant, there was some indication of positive genetic and negative environmental correlation between these traits. This shows that respective relationships are environment-specific. Nevertheless, the overall pattern of weak and inconsistent correlations between larval coloration and growth parameters does not support universal trade-offs between these traits and suggests that physiological costs of producing colour patterns do not necessarily interfere with adaptive evolution of coloration.
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Affiliation(s)
- Siiri-Lii Sandre
- Department of Zoology, Institute of Ecology and Earth Sciences, University of Tartu, Tartu, Estonia
| | - Tanel Kaart
- Department of Animal Breeding and Biotechnology, Institute of Veterinary Medicine and Animal Sciences, Estonian University of Life Sciences, Tartu, Estonia
| | - Nathan Morehouse
- Department of Biological Sciences, University of Cincinnati, Cincinnati, OH, USA
| | - Toomas Tammaru
- Department of Zoology, Institute of Ecology and Earth Sciences, University of Tartu, Tartu, Estonia
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22
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San-Jose LM, Roulin A. Toward Understanding the Repeated Occurrence of Associations between Melanin-Based Coloration and Multiple Phenotypes. Am Nat 2018; 192:111-130. [PMID: 30016163 DOI: 10.1086/698010] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Melanin is the most widespread pigment in organisms. Melanin-based coloration has been repeatedly observed to be associated with the same traits and in the same direction in different vertebrate and insect species. However, whether any factors that are common to different taxa account for the repeated evolution of melanin-phenotype associations remains unclear. We propose to approach this question from the perspective of convergent and parallel evolution to clarify to what extent different species have evolved the same associations owing to a shared genetic basis and being subjected to similar selective pressures. Our current understanding of the genetic basis of melanin-phenotype associations allows for both convergent and parallel evolution, but this understanding is still limited. Further research is needed to clarify the generality and interdependencies of the different proposed mechanisms (supergenes, pleiotropy based on hormones, or neural crest cells). The general ecological scenarios whereby melanin-based coloration is under selection-protection from ultraviolet radiation, thermoregulation in cold environments, or as a signal of social status-offer a good opportunity to study how melanin-phenotype associations evolve. Reviewing these scenarios shows that some traits associated with melanin-based coloration might be selected together with coloration by also favoring adaptation but that other associated traits might impede adaptation, which may be indicative of genetic constraints. We therefore encourage further research on the relative roles that selection and genetic constraints play in shaping multiple melanin-phenotype associations. Placed into a phylogenetic context, this will help clarify to what extent these associations result from convergent or parallel evolutionary processes and why melanin-phenotype associations are so common across the tree of life.
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23
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Baudach A, Lee K, Vogel H, Vilcinskas A. Immunological larval polyphenism in the map butterfly Araschnia levana reveals the photoperiodic modulation of immunity. Ecol Evol 2018; 8:4891-4898. [PMID: 29876067 PMCID: PMC5980286 DOI: 10.1002/ece3.4047] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Revised: 02/21/2018] [Accepted: 03/09/2018] [Indexed: 12/31/2022] Open
Abstract
The bivoltine European map butterfly (Araschnia levana) displays seasonal polyphenism characterized by the formation of two remarkably distinct dorsal wing phenotypes: The spring generation (A. levana levana) is predominantly orange with black spots and develops from diapause pupae, whereas the summer generation (A. levana prorsa) has black, white, and orange bands and develops from subitaneous pupae. The choice between spring or summer imagoes is regulated by the photoperiod during larval and prepupal development, but polyphenism in the larvae has not been investigated before. Recently, it has been found that the prepupae of A. levana display differences in immunity-related gene expression, so we tested whether larvae destined to become spring (short-day) or summer (long-day) morphs also display differences in innate immunity. We measured larval survival following the injection of a bacterial entomopathogen (Pseudomonas entomophila), the antimicrobial activity in their hemolymph and the induced expression of selected genes encoding antimicrobial peptides (AMPs). Larvae of the short-day generation died significantly later, exhibited higher antibacterial activity in the hemolymph, and displayed higher induced expression levels of AMPs than those of the long-day generation. Our study expands the seasonal polyphenism of A. levana beyond the morphologically distinct spring and summer imagoes to include immunological larval polyphenism that reveals the photoperiodic modulation of immunity. This may reflect life-history traits that manifest as trade-offs between immunity and fecundity.
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Affiliation(s)
- Arne Baudach
- Institute for Insect BiotechnologyJustus Liebig UniversityGiessenGermany
| | - Kwang‐Zin Lee
- Institute for Insect BiotechnologyJustus Liebig UniversityGiessenGermany
| | - Heiko Vogel
- Max‐Planck Institute for Chemical EcologyJenaGermany
| | - Andreas Vilcinskas
- Institute for Insect BiotechnologyJustus Liebig UniversityGiessenGermany
- Department BioresourcesFraunhofer Institute for Molecular Biology and Applied EcologyGiessenGermany
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24
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Kuyucu AC, Sahin MK, Caglar SS. The relation between melanism and thermal biology in a colour polymorphic bush cricket, Isophya rizeensis. J Therm Biol 2018; 71:212-220. [PMID: 29301693 DOI: 10.1016/j.jtherbio.2017.11.017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Revised: 11/26/2017] [Accepted: 11/27/2017] [Indexed: 11/28/2022]
Abstract
According to the thermal melanism hypothesis, darker coloured melanic individuals heat up faster and to higher temperatures than lighter coloured individuals due to lower skin reflectance. Consequently, it is assumed that darker melanic types may be advantageous compared to light coloured types in colder regions. As temperature gradually decreases with elevation and latitude the degree of melanism is expected to increase along these gradients in ectothermic species. Isophya rizeensis, a colour polymorphic bush cricket species endemic to Northeastern Turkey is an interesting case since the degree of melanism decreases with elevation, contrary to the thermal melanism hypothesis. In order to investigate the relation between colouration and thermal biology of this species, body temperatures (Tb) of crickets from different colour morphs, environmental temperatures (Ta), solar radiation and vegetation height were measured to test the relation between these variables and thermoregulation. Field results showed that solar radiation was the most effective factor on temperature excess (Tex), the difference between body and ambient temperature. Additionally, Tex values showed negative correlation with vegetation height. Although Tex values did not differ significantly between colour morphs, paired experiments under sunlight showed that darker morphs heated up faster and attained higher body temperatures than light morphs. We conclude that, since higher Tex values at alpine short swards might also increase the risk of facing deleterious temperatures at high elevations, protection against overheating might be one of the factors responsible for this polymorphism.
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Affiliation(s)
- Arda Cem Kuyucu
- Hacettepe University, Department of Biology, Faculty of Science, Ankara, Turkey.
| | - Mehmet Kursat Sahin
- Hacettepe University, Department of Biology, Faculty of Science, Ankara, Turkey
| | - Selim Sualp Caglar
- Hacettepe University, Department of Biology, Faculty of Science, Ankara, Turkey
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25
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Immune tolerance to an intestine-adapted bacteria, Chryseobacterium sp., injected into the hemocoel of Protaetia brevitarsis seulensis. Sci Rep 2016; 6:31722. [PMID: 27530146 PMCID: PMC4987663 DOI: 10.1038/srep31722] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Accepted: 07/22/2016] [Indexed: 11/11/2022] Open
Abstract
To explore the interaction of gut microbes and the host immune system, bacteria were isolated from the gut of Protaetia brevitarsis seulensis larvae. Chryseobacterium sp., Bacillus subtilis, Arthrobacter arilaitensis, Bacillus amyloliquefaciens, Bacillus megaterium, and Lysinibacillus xylanilyticus were cultured in vitro, identified, and injected in the hemocoel of P. brevitarsis seulensis larvae, respectively. There were no significant changes in phagocytosis-associated lysosomal formation or pathogen-related autophagosome in immune cells (granulocytes) from Chryseobacterium sp.-challenged larvae. Next, we examined changes in the transcription of innate immune genes such as peptidoglycan recognition proteins and antimicrobial peptides following infection with Chryseobacterium sp. PGRP-1 and -2 transcripts, which may be associated with melanization generated by prophenoloxidase (PPO), were either highly or moderately expressed at 24 h post-infection with Chryseobacterium sp. However, PGRP-SC2 transcripts, which code for bactericidal amidases, were expressed at low levels. With respect to antimicrobial peptides, only coleoptericin was moderately expressed in Chryseobacterium sp.-challenged larvae, suggesting maintenance of an optimum number of Chryseobacterium sp. All examined genes were expressed at significantly higher levels in larvae challenged with a pathogenic bacterium. Our data demonstrated that gut-inhabiting bacteria, the Chryseobacterium sp., induced a weaker immune response than other pathogenic bacteria, E. coli K12.
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Krams I, Burghardt GM, Krams R, Trakimas G, Kaasik A, Luoto S, Rantala MJ, Krama T. A dark cuticle allows higher investment in immunity, longevity and fecundity in a beetle upon a simulated parasite attack. Oecologia 2016; 182:99-109. [PMID: 27245343 DOI: 10.1007/s00442-016-3654-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2016] [Accepted: 05/11/2016] [Indexed: 11/29/2022]
Abstract
Cuticle melanism in insects is linked to a number of life history traits: a positive relationship is hypothesized between melanism, immune function, fecundity and lifespan. However, it is not clear how activation of the immune system affects trade-offs between life history traits in female mealworm beetles (Tenebrio molitor) differing in cuticle melanization. The females with tan, brown and black cuticles examined in the present study did not differ in the intensity of encapsulation response, fecundity and longevity when their immune system was not activated. However, we found that immune activation and cuticle melanization have a significant effect on life history traits. Offspring number and lifespan decreased in females with tan and brown cuticles, while the fecundity and lifespan of black females were not affected. Importantly, we inserted the implants again and found a significant decrease in the strength of encapsulation response in females with tan and brown cuticles. In contrast, black females increased melanotic reactions against the nylon implant, suggesting immunological priming. The results show that cuticle melanization plays an important adaptive role under the risk of being infected, while the lack of these benefits before the insertion of nylon monofilaments suggests that there are costs associated with an activated immunity system.
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Affiliation(s)
- Indrikis Krams
- Department of Psychology, University of Tennessee, Knoxville, TN, USA. .,Institute of Food Safety, Animal Health and Environment BIOR, Riga, Latvia. .,Institute of Ecology and Earth Science, University of Tartu, Vanemuise 46, 51014, Tartu, Estonia.
| | - Gordon M Burghardt
- Departments of Psychology and Ecology & Evolutionary Biology, University of Tennessee, Knoxville, TN, USA
| | - Ronalds Krams
- Department of Biotechnology, Institute of Life Sciences and Technology, Daugavpils University, Daugavpils, Latvia
| | - Giedrius Trakimas
- Department of Biotechnology, Institute of Life Sciences and Technology, Daugavpils University, Daugavpils, Latvia.,Center for Ecology and Environmental Research, Vilnius University, Vilnius, Lithuania
| | - Ants Kaasik
- Institute of Ecology and Earth Science, University of Tartu, Vanemuise 46, 51014, Tartu, Estonia
| | - Severi Luoto
- English, Drama and Writing Studies & School of Psychology, University of Auckland, Auckland, New Zealand
| | - Markus J Rantala
- Department of Biology, Turku Brain and Mind Centre, University of Turku, Turku, Finland
| | - Tatjana Krama
- Department of Plant Protection, Institute of Agricultural and Environmental Sciences, Estonian University of Life Science, Tartu, Estonia
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Torres-Campos I, Abram PK, Guerra-Grenier E, Boivin G, Brodeur J. A scenario for the evolution of selective egg coloration: the roles of enemy-free space, camouflage, thermoregulation and pigment limitation. ROYAL SOCIETY OPEN SCIENCE 2016; 3:150711. [PMID: 27152215 PMCID: PMC4852638 DOI: 10.1098/rsos.150711] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 03/08/2016] [Indexed: 05/11/2023]
Abstract
Behavioural plasticity can drive the evolution of new traits in animals. In oviparous species, plasticity in oviposition behaviour could promote the evolution of new egg traits by exposing them to different selective pressures in novel oviposition sites. Individual females of the predatory stink bug Podisus maculiventris are able to selectively colour their eggs depending on leaf side, laying lightly pigmented eggs on leaf undersides and more pigmented eggs, which are more resistant to ultraviolet (UV) radiation damage, on leaf tops. Here, we propose an evolutionary scenario for P. maculiventris egg pigmentation and its selective application. We experimentally tested the influence of several ecological factors that: (i) could have favoured a behavioural shift towards laying eggs on leaf tops and thus the evolution of a UV-protective egg pigment (i.e. exploitation of enemy-reduced space or a thermoregulatory benefit) and (ii) could have subsequently led to the evolution of selective pigment application (i.e. camouflage or costly pigment production). We found evidence that a higher predation pressure on leaf undersides could have caused a shift in oviposition effort towards leaf tops. We also found the first evidence of an insect egg pigment providing a thermoregulatory advantage. Our study contributes to an understanding of how plasticity in oviposition behaviour could shape the responses of organisms to ecological factors affecting their reproductive success, spurring the evolution of new morphological traits.
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Affiliation(s)
- Inmaculada Torres-Campos
- Instituto de Hortofruticultura Subtropical y Mediterránea ‘La Mayora’, Universidad de Málaga-Consejo Superior de Investigaciones Científicas (IHSM-UMA-CSIC), Estación Experimental La Mayora, 29750 Algarrobo-Costa, Málaga, Spain
- Author for correspondence: Inmaculada Torres-Campos e-mail:
| | - Paul K. Abram
- Institut de Recherche en Biologie Végétale, Département de sciences biologiques.Université de Montréal, 4101 Sherbrooke Est, Montréal, CanadaH1X 2B2
- Centre de Recherche et de Développement en Horticulture, Agriculture et Agroalimentaire Canada, 430 Blvd. Gouin, St-Jean-sur-Richelieu, CanadaJ3B 3E6
| | - Eric Guerra-Grenier
- Institut de Recherche en Biologie Végétale, Département de sciences biologiques.Université de Montréal, 4101 Sherbrooke Est, Montréal, CanadaH1X 2B2
| | - Guy Boivin
- Centre de Recherche et de Développement en Horticulture, Agriculture et Agroalimentaire Canada, 430 Blvd. Gouin, St-Jean-sur-Richelieu, CanadaJ3B 3E6
| | - Jacques Brodeur
- Institut de Recherche en Biologie Végétale, Département de sciences biologiques.Université de Montréal, 4101 Sherbrooke Est, Montréal, CanadaH1X 2B2
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Azócar DLM, Bonino MF, Perotti MG, Schulte JA, Abdala CS, Cruz FB. Effect of body mass and melanism on heat balance in Liolaemus lizards of the goetschi clade. J Exp Biol 2016; 219:1162-71. [DOI: 10.1242/jeb.129007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Accepted: 02/08/2016] [Indexed: 11/20/2022]
Abstract
Body temperature of ectotherms depends on the environmental temperatures and behavioral adjustments, but morphology may also affect it. For example, in colder environments animals tend to be larger and show higher thermal inertia, as proposed by Bergmann's rule and the heat balance hypothesis (HBH). Additionally, dark coloration increases solar radiation absorption and should accelerate heat gain (Thermal melanism hypothesis, TMH).
We tested Bergmann's rule, HBH and TMH within the Liolaemus goetschi lizards clade that show variability in body size and melanic coloration. We measured heating and cooling rates of live and euthanized animals, and tested how morphology and color affect these rates. Live organisms show less variable and faster heating rates, compared to cooling rates, suggesting behavioral and/ or physiological adjustments.
Our results support Bergmann's rule and the HBH, as larger species show slower heating and cooling rates. However, we did not find a clear pattern to support TMH. The influence of dorsal melanism on heating by radiation was masked by body size effect in live animals, while results from euthanized individuals show no clear effects of melanism on heating rates either. However, when compared three groups of live individuals with different degree of melanism we found that that darker euthanized animals actually heat faster than lighter ones, favoring TMH. Although unresolved aspects remain, body size and coloration influenced heat exchange suggesting complex thermoregulatory strategies in these lizards, probably regulated through physiology and behavior, what may allow these small lizards to inhabit harsh weather environments.
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Affiliation(s)
- Débora Lina Moreno Azócar
- Laboratorio de Fotobiología, Instituto de Investigaciones en Biodiversidad y Medioambiente (INIBIOMA), CONICET-UNCOMA, Quintral 1250, Bariloche, 8400 Río Negro, Argentina
| | - Marcelo Fabián Bonino
- Laboratorio de Fotobiología, Instituto de Investigaciones en Biodiversidad y Medioambiente (INIBIOMA), CONICET-UNCOMA, Quintral 1250, Bariloche, 8400 Río Negro, Argentina
| | - María Gabriela Perotti
- Laboratorio de Fotobiología, Instituto de Investigaciones en Biodiversidad y Medioambiente (INIBIOMA), CONICET-UNCOMA, Quintral 1250, Bariloche, 8400 Río Negro, Argentina
| | - James A. Schulte
- Beloit College, 700 College St., Science Center 338, Beloit, WI 53511, USA
| | - Cristian Simón Abdala
- Facultad de Ciencias Naturales e I. M. Lillo (UNT), CONICET-Instituto de Herpetología (FML), Tucumán, Argentina. Miguel Lillo 205, 4000, San Miguel de Tucumán, Argentina
| | - Félix Benjamín Cruz
- Laboratorio de Fotobiología, Instituto de Investigaciones en Biodiversidad y Medioambiente (INIBIOMA), CONICET-UNCOMA, Quintral 1250, Bariloche, 8400 Río Negro, Argentina
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Acker P, Grégoire A, Rat M, Spottiswoode CN, van Dijk RE, Paquet M, Kaden JC, Pradel R, Hatchwell BJ, Covas R, Doutrelant C. Disruptive viability selection on a black plumage trait associated with dominance. J Evol Biol 2015; 28:2027-41. [PMID: 26249359 PMCID: PMC4949555 DOI: 10.1111/jeb.12717] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Revised: 07/26/2015] [Accepted: 08/01/2015] [Indexed: 11/30/2022]
Abstract
Traits used in communication, such as colour signals, are expected to have positive consequences for reproductive success, but their associations with survival are little understood. Previous studies have mainly investigated linear relationships between signals and survival, but both hump-shaped and U-shaped relationships can also be predicted, depending on the main costs involved in trait expression. Furthermore, few studies have taken the plasticity of signals into account in viability selection analyses. The relationship between signal expression and survival is of particular interest in melanin-based traits, because their main costs are still debated. Here, we first determined the main factors explaining variability in a melanin-based trait linked to dominance: the bib size of a colonial bird, the sociable weaver Philetairus socius. We then used these analyses to obtain a measure representative of the individual mean expression of bib size. Finally, we used capture-recapture models to study how survival varied in relation to bib size. Variation in bib size was strongly affected by year and moderately affected by age, body condition and colony size. In addition, individuals bearing small and large bibs had higher survival than those with intermediate bibs, and this U-shaped relationship between survival and bib size appeared to be more pronounced in some years than others. These results constitute a rare example of disruptive viability selection, and point towards the potential importance of social costs incurred by the dominance signalling function of badges of status.
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Affiliation(s)
- P Acker
- CEFE UMR 5175, CNRS - Université de Montpellier - Université Paul-Valéry Montpellier - EPHE, Montpellier Cedex 05, France.,Laboratoire Évolution & Diversité Biologique (UMR 5174 EDB), Université Toulouse 3 Paul Sabatier - CNRS - ENFA, Toulouse, France
| | - A Grégoire
- CEFE UMR 5175, CNRS - Université de Montpellier - Université Paul-Valéry Montpellier - EPHE, Montpellier Cedex 05, France
| | - M Rat
- Percy FitzPatrick Institute, DST-NRF Centre of Excellence, University of Cape Town, Rondebosch, South Africa
| | - C N Spottiswoode
- Percy FitzPatrick Institute, DST-NRF Centre of Excellence, University of Cape Town, Rondebosch, South Africa.,Department of Zoology, University of Cambridge, Cambridge, UK
| | - R E van Dijk
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield, UK
| | - M Paquet
- CEFE UMR 5175, CNRS - Université de Montpellier - Université Paul-Valéry Montpellier - EPHE, Montpellier Cedex 05, France.,Percy FitzPatrick Institute, DST-NRF Centre of Excellence, University of Cape Town, Rondebosch, South Africa
| | - J C Kaden
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield, UK.,The Royal Zoological Society of Scotland, Edinburgh Zoo, Edinburgh, UK
| | - R Pradel
- CEFE UMR 5175, CNRS - Université de Montpellier - Université Paul-Valéry Montpellier - EPHE, Montpellier Cedex 05, France
| | - B J Hatchwell
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield, UK
| | - R Covas
- Percy FitzPatrick Institute, DST-NRF Centre of Excellence, University of Cape Town, Rondebosch, South Africa.,CIBIO, University of Porto, Vairão, Portugal.,Biology Department, Science Faculty, University of Porto, Porto, Portugal
| | - C Doutrelant
- CEFE UMR 5175, CNRS - Université de Montpellier - Université Paul-Valéry Montpellier - EPHE, Montpellier Cedex 05, France.,Percy FitzPatrick Institute, DST-NRF Centre of Excellence, University of Cape Town, Rondebosch, South Africa
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Valverde JP, Schielzeth H. What triggers colour change? Effects of background colour and temperature on the development of an alpine grasshopper. BMC Evol Biol 2015; 15:168. [PMID: 26293296 PMCID: PMC4546165 DOI: 10.1186/s12862-015-0419-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2014] [Accepted: 06/15/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Colour polymorphisms are a fascinating facet of many natural populations of plants and animals, and the selective processes that maintain such variation are as relevant as the processes which promote their development. Orthoptera, the insect group that encompasses grasshoppers and bush crickets, includes a particularly large number of species that are colour polymorphic with a marked green-brown polymorphism being particularly widespread. Colour polymorphism has been associated with the need for crypsis and background matching and background-dependent homochromy has been described in a few species. However, when and how different environmental conditions influence variation in colour remains poorly understood. Here we test for effects of background colour and ambient temperature on the occurrence of colour morph switches (green to brown or brown to green) and developmental darkening in the alpine dwelling club-legged grasshopper Gomphocerus sibiricus. RESULTS We monitored individually housed nymphae across three of their four developmental stages and into the first week after final ecdysis. Our data show an absence of colour morph switches in G. sibiricus, without a single switch observed in our sample. Furthermore, we test for an effect of temperature on colouration by manipulating radiant heat, a limiting factor in alpine habitats. Radiant heat had a significant effect on developmental darkening: individuals under low radiant heat tended to darken, while individuals under high radiant heat tended to lighten within nymphal stages. Young imagoes darkened under either condition. CONCLUSIONS Our results indicate a plastic response to a variable temperature and indicate that melanin, a multipurpose pigment responsible for dark colouration and presumed to be costly, seems to be strategically allocated according to the current environmental conditions. Unlike other orthopterans, the species is apparently unable to switch colour morphs (green/brown) during development, suggesting that colour morphs are determined genetically (or very early during development) and that other processes have to contribute to crypsis and homochromy in this species.
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Affiliation(s)
- J Pablo Valverde
- Department of Evolutionary Biology, Bielefeld University, Morgenbreede 45, 33615, Bielefeld, Germany.
| | - Holger Schielzeth
- Department of Evolutionary Biology, Bielefeld University, Morgenbreede 45, 33615, Bielefeld, Germany.
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31
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Sartori C, Mazza S, Guzzo N, Mantovani R. Evolution of increased competitiveness in cows trades off with reduced milk yield, fertility and more masculine morphology. Evolution 2015; 69:2235-45. [PMID: 26177581 DOI: 10.1111/evo.12723] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Revised: 06/03/2015] [Accepted: 06/22/2015] [Indexed: 12/11/2022]
Abstract
In some species females compete for food, foraging territories, mating, and nesting sites. Competing females can exhibit morphological, physiological, and behavioral adaptations typical of males, which are commonly considered as secondary sexual traits. Competition and the development of traits increasing competitiveness require much energy and may exert adverse effects on fecundity and survival. From an evolutionary perspective, positive selection for increased competitiveness would then result in evolution of reduced values for traits related to fitness such as fecundity and survival. There is recent evidence for such evolutionary trade-offs involving male competition, but no study has considered competing females so far. Using data from competitions for dominance in cows (Bos taurus), we found negative genetic correlations between traits providing success in competition, that is, fighting ability and fitness traits related to milk production and with fertility (the inverse of parity-conception interval). Fighting ability also showed low but positive genetic correlations with "masculine" morphological traits, and negative correlations with "feminine" traits. A genetic change in traits over time has occurred due to selection on competitiveness, corresponding to an evolutionary process of "masculinization" counteracting the official selection for milk yield. Similar evolutionary trade-off between success in competition and fitness components may be present in various species experiencing female competition.
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Affiliation(s)
- Cristina Sartori
- Department of Agronomy, Food, Natural Resources, Animals and Environment-DAFNAE, University of Padua, Viale dell'Universita', 16, 35020, Legnaro, PD, Italy.
| | - Serena Mazza
- Department of Agronomy, Food, Natural Resources, Animals and Environment-DAFNAE, University of Padua, Viale dell'Universita', 16, 35020, Legnaro, PD, Italy
| | - Nadia Guzzo
- Department of Agronomy, Food, Natural Resources, Animals and Environment-DAFNAE, University of Padua, Viale dell'Universita', 16, 35020, Legnaro, PD, Italy
| | - Roberto Mantovani
- Department of Agronomy, Food, Natural Resources, Animals and Environment-DAFNAE, University of Padua, Viale dell'Universita', 16, 35020, Legnaro, PD, Italy
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Liu S, Wang M, Li X. Pupal melanization is associated with higher fitness in Spodoptera exigua. Sci Rep 2015; 5:10875. [PMID: 26039886 PMCID: PMC4454190 DOI: 10.1038/srep10875] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2015] [Accepted: 05/05/2015] [Indexed: 11/09/2022] Open
Abstract
Melanism has long been thought to be a habitat adaptation with a fitness cost. Here we reported a homozygous melanic strain (SEM) of Spodoptera exigua (Hübner) (Insecta: Lepidoptera: Noctuidae) established with black pupae spontaneously occurring within a typical laboratory population (SEW). The melanization is expressed globally, and only in the pupal stage. After pupation, the melanic SEM pupae gradually accumulate melanin to become completely black within 6 hours, whereas the wild-type SEW pupae gradually turn yellow-brown. The melanic SEM strain exhibits faster development in all life stages, heavier pupa weight, more mating time, higher fecundity, and accordingly, higher net reproductive rate and population trend index. While no reproductive isolation was observed between the SEM and SEW strains, the mating times per female of the reciprocal crosses and the SEM intracrosses were significantly higher than those of the SEW intracrosses. This represents a rare case of melanization that has fitness gains, rather than costs. Analysis of the life-history traits of this case and 14 previously reported cases of insect melanism indicate that none of melanization origin, stage, space and variation type determining whether melanism will cause fitness gain or cost.
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Affiliation(s)
- Sisi Liu
- 1] Department of Pesticide Science, College of Plant Science &Technology, Huazhong Agricultural University, Wuhan 430070, China [2] Department of Entomology and BIO5 Institute, University of Arizona, Tucson, Arizona [3] Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, Institute of Insect Resources, Huazhong Agricultural University, Wuhan 430070, China
| | - Mo Wang
- 1] Department of Pesticide Science, College of Plant Science &Technology, Huazhong Agricultural University, Wuhan 430070, China [2] Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, Institute of Insect Resources, Huazhong Agricultural University, Wuhan 430070, China
| | - Xianchun Li
- 1] Department of Entomology and BIO5 Institute, University of Arizona, Tucson, Arizona [2] State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
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Stahlschmidt ZR, Acker M, Kovalko I, Adamo SA. The double‐edged sword of immune defence and damage control: do food availability and immune challenge alter the balance? Funct Ecol 2015. [DOI: 10.1111/1365-2435.12454] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
| | - Madison Acker
- Dalhousie University Halifax Nova Scotia B3H 4R2 Canada
| | - Ilya Kovalko
- Dalhousie University Halifax Nova Scotia B3H 4R2 Canada
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Merckx T, Serruys M, Van Dyck H. Anthropogenic host plant expansion leads a nettle-feeding butterfly out of the forest: consequences for larval survival and developmental plasticity in adult morphology. Evol Appl 2015; 8:363-72. [PMID: 25926881 PMCID: PMC4408147 DOI: 10.1111/eva.12249] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2014] [Accepted: 01/03/2015] [Indexed: 12/31/2022] Open
Abstract
Recent anthropogenic eutrophication has meant that host plants of nettle-feeding insects became quasi-omnipresent in fertile regions of Western Europe. However, host plant resource quality – in terms of microclimate and nutritional value – may vary considerably between the ‘original’ forest habitat and ‘recent’ agricultural habitat. Here, we compared development in both environmental settings using a split-brood design, so as to explore to what extent larval survival and adult morphology in the nettle-feeding butterfly Aglais urticae are influenced by the anthropogenic environment. Nettles along field margins had higher C/N ratios and provided warmer microclimates to larvae. Larvae developed 20% faster and tended to improve their survival rates, on the agricultural land compared to woodland. Our split-brood approach indicated plastic responses within families, but also family effects in the phenotypic responses. Adult males and females had darker wing pigmentation in the drier and warmer agricultural environment, which contrasts with the thermal melanism hypothesis. Developmental plasticity in response to this microclimatically different and more variable habitat was associated with a broader phenotypic parameter space for the species. Both habitat expansion and developmental plasticity are likely contributors to the ecological and evolutionary success of these nettle-feeding insects in anthropogenic environments under high nitrogen load.
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Affiliation(s)
- Thomas Merckx
- Behavioural Ecology and Conservation Group, Biodiversity Research Centre, Earth and Life Institute, Université catholique de Louvain Louvain-la-Neuve, Belgium
| | - Mélanie Serruys
- Behavioural Ecology and Conservation Group, Biodiversity Research Centre, Earth and Life Institute, Université catholique de Louvain Louvain-la-Neuve, Belgium
| | - Hans Van Dyck
- Behavioural Ecology and Conservation Group, Biodiversity Research Centre, Earth and Life Institute, Université catholique de Louvain Louvain-la-Neuve, Belgium
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Välimäki P, Kivelä SM, Raitanen J, Pakanen VM, Vatka E, Mäenpää MI, Keret N, Tammaru T. Larval melanism in a geometrid moth: promoted neither by a thermal nor seasonal adaptation but desiccating environments. J Anim Ecol 2015; 84:817-828. [PMID: 25581258 DOI: 10.1111/1365-2656.12330] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Accepted: 12/17/2014] [Indexed: 11/27/2022]
Abstract
Spatiotemporal variation in the degree of melanism is often considered in the context of thermal adaptation, melanism being advantageous under suboptimal thermal conditions. Yet, other mutually nonexclusive explanations exist. Analysis of geographical patterns combined with laboratory experiments on the mechanisms of morph induction helps to unveil the adaptive value of particular cases of polyphenism. In the context of the thermal melanism hypothesis and seasonal adaptations, we explored an array of environmental factors that may affect the expression and performance of nonmelanic vs. melanic larval morphs in different latitudinal populations of the facultatively bivoltine moth Chiasmia clathrata (Lepidoptera: Geometridae). Geographical variation in larval coloration was independent of average temperatures experienced by the populations in the wild. The melanic morph was, however, more abundant in dry than in mesic habitats. In the laboratory, the melanic morph was induced especially under a high level of incident radiation but also at relatively high temperatures, but independently of photoperiod. Melanic larvae had higher growth rates and shorter development times than the nonmelanic ones when both temperature and the level of incident radiation were high. Our results that melanism is induced and advantageous in warm desiccating conditions contradict the thermal melanism hypothesis for this species. Neither has melanism evolved to compensate time constraints due to forthcoming autumn. Instead, larvae solve seasonal variation in the time available for growth by an elevated growth rate and a shortened larval period in the face of autumnal photoperiods. The phenotypic response to the level of incident radiation and a lack of adaptive adjustment of larval growth trajectories in univoltine populations underpin the role of deterministic environmental variation in the evolution of irreversible adaptive plasticity and seasonal polyphenism.
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Affiliation(s)
- Panu Välimäki
- Department of Ecology, University of Oulu, PO Box 3000, Oulu, FI-90014, Finland
| | - Sami M Kivelä
- Department of Ecology, University of Oulu, PO Box 3000, Oulu, FI-90014, Finland
| | - Jani Raitanen
- Department of Ecology, University of Oulu, PO Box 3000, Oulu, FI-90014, Finland
| | - Veli-Matti Pakanen
- Department of Ecology, University of Oulu, PO Box 3000, Oulu, FI-90014, Finland
| | - Emma Vatka
- Department of Ecology, University of Oulu, PO Box 3000, Oulu, FI-90014, Finland
| | - Maarit I Mäenpää
- Department of Ecology, University of Oulu, PO Box 3000, Oulu, FI-90014, Finland
| | - Netta Keret
- Department of Ecology, University of Oulu, PO Box 3000, Oulu, FI-90014, Finland
| | - Toomas Tammaru
- Institute of Ecology and Earth Sciences, University of Tartu, Vanemuise 46, Tartu, EE-51014, Estonia
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Conchou L, Cabioch L, Rodriguez LJV, Kjellberg F. Daily rhythm of mutualistic pollinator activity and scent emission in Ficus septica: ecological differentiation between co-occurring pollinators and potential consequences for chemical communication and facilitation of host speciation. PLoS One 2014; 9:e103581. [PMID: 25105796 PMCID: PMC4126690 DOI: 10.1371/journal.pone.0103581] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Accepted: 07/04/2014] [Indexed: 11/18/2022] Open
Abstract
The mutualistic interaction between Ficus and their pollinating agaonid wasps constitutes an extreme example of plant-insect co-diversification. Most Ficus species are locally associated with a single specific agaonid wasp species. Specificity is ensured by each fig species emitting a distinctive attractive scent. However, cases of widespread coexistence of two agaonid wasp species on the same Ficus species are documented. Here we document the coexistence of two agaonid wasp species in Ficus septica: one yellow-colored and one black-colored. Our results suggest that their coexistence is facilitated by divergent ecological traits. The black species is longer-lived (a few more hours) and is hence active until later in the afternoon. Some traits of the yellow species must compensate for this advantage for their coexistence to be stable. In addition, we show that the composition of the scent emitted by receptive figs changes between sunrise and noon. The two species may therefore be exposed to somewhat different ranges of receptive fig scent composition and may consequently diverge in the way they perceive and/or respond to scents. Whether such situations may lead to host plant speciation is an open question.
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Affiliation(s)
- Lucie Conchou
- CEFE UMR 5175, CNRS - Université de Montpellier - Université Paul-Valéry Montpellier – EPHE, Montpellier, France
- * E-mail:
| | - Léa Cabioch
- CEFE UMR 5175, CNRS - Université de Montpellier - Université Paul-Valéry Montpellier – EPHE, Montpellier, France
| | - Lillian J. V. Rodriguez
- CEFE UMR 5175, CNRS - Université de Montpellier - Université Paul-Valéry Montpellier – EPHE, Montpellier, France
- Institute of Biology, University of the Philippines Diliman, Quezon City, Philippines
| | - Finn Kjellberg
- CEFE UMR 5175, CNRS - Université de Montpellier - Université Paul-Valéry Montpellier – EPHE, Montpellier, France
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Perrard A, Arca M, Rome Q, Muller F, Tan J, Bista S, Nugroho H, Baudoin R, Baylac M, Silvain JF, Carpenter JM, Villemant C. Geographic variation of melanisation patterns in a hornet species: genetic differences, climatic pressures or aposematic constraints? PLoS One 2014; 9:e94162. [PMID: 24740142 PMCID: PMC3989226 DOI: 10.1371/journal.pone.0094162] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2013] [Accepted: 03/11/2014] [Indexed: 01/13/2023] Open
Abstract
Coloration of stinging insects is often based on contrasted patterns of light and black pigmentations as a warning signal to predators. However, in many social wasp species, geographic variation drastically modifies this signal through melanic polymorphism potentially driven by different selective pressures. To date, surprisingly little is known about the geographic variation of coloration of social wasps in relation to aposematism and melanism and to genetic and developmental constraints. The main objectives of this study are to improve the description of the colour variation within a social wasp species and to determine which factors are driving this variation. Therefore, we explored the evolutionary history of a polymorphic hornet, Vespa velutina Lepeletier, 1836, using mitochondrial and microsatellite markers, and we analysed its melanic variation using a colour space based on a description of body parts coloration. We found two main lineages within the species and confirmed the previous synonymy of V. auraria Smith, 1852, under V. velutina, differing only by the coloration. We also found that the melanic variation of most body parts was positively correlated, with some segments forming potential colour modules. Finally, we showed that the variation of coloration between populations was not related to their molecular, geographic or climatic differences. Our observations suggest that the coloration patterns of hornets and their geographic variations are determined by genes with an influence of developmental constraints. Our results also highlight that Vespa velutina populations have experienced several convergent evolutions of the coloration, more likely influenced by constraints on aposematism and Müllerian mimicry than by abiotic pressures on melanism.
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Affiliation(s)
- Adrien Perrard
- UMR 7205 ISYEB, Muséum National d'Histoire Naturelle, Paris, France
- Division of Invertebrate Zoology, American Museum of Natural History, New York, New York, United States of America
- * E-mail:
| | - Mariangela Arca
- Unité de Recherche IRD 072-UPR9034 CNRS, Laboratoire Evolution Génomes et Spéciation, Gif-sur-Yvette, France
- Université Paris-Sud 11, Orsay, France
| | - Quentin Rome
- UMR 7205 ISYEB, Muséum National d'Histoire Naturelle, Paris, France
| | - Franck Muller
- UMR 7205 ISYEB, Muséum National d'Histoire Naturelle, Paris, France
| | - Jiangli Tan
- School of Life Sciences, Northwest University, Xi'an, Shaanxi, China
| | - Sanjaya Bista
- Entomology Division, Nepal Agricultural Research Council (NARC), Lalitpur, Nepal
| | - Hari Nugroho
- Museum Zoologicum Bogoriense, Indonesian Institute of Sciences, Cibinong, Bogor, Indonesia
| | | | - Michel Baylac
- UMR 7205 ISYEB, Muséum National d'Histoire Naturelle, Paris, France
| | - Jean-François Silvain
- Unité de Recherche IRD 072-UPR9034 CNRS, Laboratoire Evolution Génomes et Spéciation, Gif-sur-Yvette, France
- Université Paris-Sud 11, Orsay, France
| | - James M. Carpenter
- Division of Invertebrate Zoology, American Museum of Natural History, New York, New York, United States of America
| | - Claire Villemant
- UMR 7205 ISYEB, Muséum National d'Histoire Naturelle, Paris, France
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Two genomic regions together cause dark abdominal pigmentation in Drosophila tenebrosa. Heredity (Edinb) 2013; 112:454-62. [PMID: 24326291 DOI: 10.1038/hdy.2013.124] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Revised: 10/21/2013] [Accepted: 10/22/2013] [Indexed: 11/08/2022] Open
Abstract
Pigmentation is a rapidly evolving trait that is under both natural and sexual selection in many organisms. In the quinaria group of Drosophila, nearly all of the 30 species have an abdomen that is light in color with distinct markings; D. tenebrosa is the exception in that it has a completely melanic abdomen with no visible markings. In this study, we use a combination of quantitative genetic and candidate gene approaches to investigate the genetic basis of abdominal pigmentation in D. tenebrosa. We find that abdominal pigmentation is invariant across wild-caught lines of D. tenebrosa and is not sexually dimorphic. Quantitative genetic mapping utilizing crosses between D. tenebrosa and the light-colored D. suboccidentalis indicates that two genomic regions together underlie abdominal pigmentation, including the X-chromosome and an autosome (Muller Element C/E). Further support for their central importance in pigmentation is that experimental introgression of one phenotype into the other species, in either direction, results in introgression of these two genomic regions. Finally, the expression of the X-linked gene yellow in the pupae exactly foreshadows the adult melanization pattern in the abdomen of both species, suggesting that changes in the regulation of yellow are important for the phenotypic divergence of D. tenebrosa from the rest of the quinaria group. These results contribute to a body of work that demonstrates how changes in expression of highly conserved genes can cause substantial phenotypic differences even between closely related species.
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