1
|
Hitchcock TJ, Gardner A. Sexual antagonism in sequential hermaphrodites. Proc Biol Sci 2023; 290:20232222. [PMID: 37989243 PMCID: PMC10688264 DOI: 10.1098/rspb.2023.2222] [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: 09/30/2023] [Accepted: 10/30/2023] [Indexed: 11/23/2023] Open
Abstract
Females and males may have distinct phenotypic optima, but share essentially the same complement of genes, potentially leading to trade-offs between attaining high fitness through female versus male reproductive success. Such sexual antagonism may be particularly acute in hermaphrodites, where both reproductive strategies are housed within a single individual. While previous models have focused on simultaneous hermaphroditism, we lack theory for how sexual antagonism may play out under sequential hermaphroditism, which has the additional complexities of age-structure. Here, we develop a formal theory of sexual antagonism in sequential hermaphrodites. First, we construct a general theoretical overview of the problem, then consider different types of sexually antagonistic and life-history trade-offs, under different modes of genetic inheritance (autosomal or cytoplasmic), and different forms of sequential hermaphroditism (protogynous, protoandrous or bidirectional). Finally, we provide a concrete illustration of these general patterns by developing a two-stage two-sex model, which yields conditions for both invasion of sexually antagonistic alleles and maintenance of sexually antagonistic polymorphisms.
Collapse
Affiliation(s)
- Thomas J. Hitchcock
- RIKEN Interdisciplinary Theoretical and Mathematical Sciences (iTHEMS), RIKEN, Wako, Saitama 351-0198, Japan
- School of Biology, University of St Andrews, St Andrews, Fife KY16 9TH, UK
| | - Andy Gardner
- School of Biology, University of St Andrews, St Andrews, Fife KY16 9TH, UK
| |
Collapse
|
2
|
de Vries C, Lehtonen J. Sex-specific assumptions and their importance in models of sexual selection. Trends Ecol Evol 2023; 38:927-935. [PMID: 37246084 DOI: 10.1016/j.tree.2023.04.013] [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: 10/15/2022] [Revised: 04/14/2023] [Accepted: 04/24/2023] [Indexed: 05/30/2023]
Abstract
Sexual selection is a field coloured by tension and contrasting views. One contested claim is the causal link from the definition of the sexes (anisogamy) to divergent selection on the sexes. Does theory truly engage with this claim? We survey the extent to which theory makes sex-specific assumptions and engages with anisogamy, and discuss these issues in a broader context. The majority of theory in sexual selection makes sex-specific assumptions and does not engage with the definition of the sexes. While this does not invalidate existing results, debates and criticisms regarding sexual selection force us to think deeper about its logical foundations. We discuss ways to strengthen the foundations of sexual selection theory by relaxing central assumptions.
Collapse
Affiliation(s)
- Charlotte de Vries
- Department of Biological and Environmental Science, University of Jyväskylä, Jyväskylä 40014, Finland; Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, The Netherlands.
| | - Jussi Lehtonen
- Department of Biological and Environmental Science, University of Jyväskylä, Jyväskylä 40014, Finland.
| |
Collapse
|
3
|
Price PD, Parkus SM, Wright AE. Recent progress in understanding the genomic architecture of sexual conflict. Curr Opin Genet Dev 2023; 80:102047. [PMID: 37163877 DOI: 10.1016/j.gde.2023.102047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 04/02/2023] [Accepted: 04/02/2023] [Indexed: 05/12/2023]
Abstract
Genomic conflict between the sexes over shared traits is widely assumed to be resolved through the evolution of sex-biased expression and the subsequent emergence of sexually dimorphic phenotypes. However, while there is support for a broad relationship between genome-wide patterns of expression level and sexual conflict, recent studies suggest that sex differences in the nature and strength of interactions between loci are instead key to conflict resolution. Furthermore, the advent of new technologies for measuring and perturbing expression means we now have much more power to detect genomic signatures of sexual conflict. Here, we review our current understanding of the genomic architecture of sexual conflict in the light of these new studies and highlight the potential for novel approaches to address outstanding knowledge gaps.
Collapse
Affiliation(s)
- Peter D Price
- Ecology and Evolutionary Biology, School of Biosciences, University of Sheffield, United Kingdom. https://twitter.com/@PeterDPrice
| | - Sylvie M Parkus
- Ecology and Evolutionary Biology, School of Biosciences, University of Sheffield, United Kingdom
| | - Alison E Wright
- Ecology and Evolutionary Biology, School of Biosciences, University of Sheffield, United Kingdom.
| |
Collapse
|
4
|
Svensson EI. Why high-condition males might be bad news for females and populations. Proc Natl Acad Sci U S A 2023; 120:e2301989120. [PMID: 36913584 PMCID: PMC10041060 DOI: 10.1073/pnas.2301989120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/14/2023] Open
Affiliation(s)
- Erik I. Svensson
- Department of Biology, Evolutionary Ecology Unit, Lund University, LundSE-223 62, Sweden
| |
Collapse
|
5
|
Ellis S, Johnstone RA, Cant MA, Franks DW, Weiss MN, Alberts SC, Balcomb KC, Benton CH, Brent LJN, Crockford C, Davidian E, Delahay RJ, Ellifrit DK, Höner OP, Meniri M, McDonald RA, Nichols HJ, Thompson FJ, Vigilant L, Wittig RM, Croft DP. Patterns and consequences of age-linked change in local relatedness in animal societies. Nat Ecol Evol 2022; 6:1766-1776. [PMID: 36163259 PMCID: PMC10423498 DOI: 10.1038/s41559-022-01872-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Accepted: 08/01/2022] [Indexed: 11/09/2022]
Abstract
The ultimate payoff of behaviours depends not only on their direct impact on an individual, but also on the impact on their relatives. Local relatedness-the average relatedness of an individual to their social environment-therefore has profound effects on social and life history evolution. Recent work has begun to show that local relatedness has the potential to change systematically over an individual's lifetime, a process called kinship dynamics. However, it is unclear how general these kinship dynamics are, whether they are predictable in real systems and their effects on behaviour and life history evolution. In this study, we combine modelling with data from real systems to explore the extent and impact of kinship dynamics. We use data from seven group-living mammals with diverse social and mating systems to demonstrate not only that kinship dynamics occur in animal systems, but also that the direction and magnitude of kinship dynamics can be accurately predicted using a simple model. We use a theoretical model to demonstrate that kinship dynamics can profoundly affect lifetime patterns of behaviour and can drive sex differences in helping and harming behaviour across the lifespan in social species. Taken together, this work demonstrates that kinship dynamics are likely to be a fundamental dimension of social evolution, especially when considering age-linked changes and sex differences in behaviour and life history.
Collapse
Affiliation(s)
- Samuel Ellis
- Centre for Research in Animal Behaviour, University of Exeter, Exeter, UK.
| | | | - Michael A Cant
- Centre for Ecology and Conservation, University of Exeter, Penryn Campus, Penryn, UK
| | | | - Michael N Weiss
- Centre for Research in Animal Behaviour, University of Exeter, Exeter, UK
- Center for Whale Research, Friday Harbor, WA, USA
| | - Susan C Alberts
- Department of Biology, Duke University, Durham, NC, USA
- Department of Evolutionary Anthropology, Duke University, Durham, NC, USA
| | | | - Claire H Benton
- National Wildlife Management Centre, Animal and Plant Health Agency, Sand Hutton, York, UK
| | - Lauren J N Brent
- Centre for Research in Animal Behaviour, University of Exeter, Exeter, UK
| | - Catherine Crockford
- Institut des Sciences Cognitives, CNRS, Lyon, France
- Department of Human Behavior, Ecology and Culture, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
- Taï Chimpanzee Project, Centre Suisse de Recherches Scientifique, Abidjan, Côte d'Ivoire
- Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Eve Davidian
- Department of Evolutionary Ecology, Leibniz Institute for Zoo and Wildlife Research, Berlin, Germany
- Ngorongoro Hyena Project, Ngorongoro Conservation Area, Arusha, Tanzania
| | - Richard J Delahay
- National Wildlife Management Centre, Animal and Plant Health Agency, Sand Hutton, York, UK
| | | | - Oliver P Höner
- Department of Evolutionary Ecology, Leibniz Institute for Zoo and Wildlife Research, Berlin, Germany
- Ngorongoro Hyena Project, Ngorongoro Conservation Area, Arusha, Tanzania
| | - Magali Meniri
- Centre for Ecology and Conservation, University of Exeter, Penryn Campus, Penryn, UK
| | - Robbie A McDonald
- Environment and Sustainability Institute, University of Exeter, Penryn Campus, Penryn, UK
| | | | - Faye J Thompson
- Centre for Ecology and Conservation, University of Exeter, Penryn Campus, Penryn, UK
| | - Linda Vigilant
- Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Roman M Wittig
- Department of Human Behavior, Ecology and Culture, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
- Taï Chimpanzee Project, Centre Suisse de Recherches Scientifique, Abidjan, Côte d'Ivoire
- German Centre for Integrative Biodiversity Research, Leipzig, Germany
| | - Darren P Croft
- Centre for Research in Animal Behaviour, University of Exeter, Exeter, UK
| |
Collapse
|
6
|
Kane A, Ayllón D, O’Sullivan RJ, McGinnity P, Reed TE. Escalating the conflict? Intersex genetic correlations influence adaptation to environmental change in facultatively migratory populations. Evol Appl 2022; 15:773-789. [PMID: 35603024 PMCID: PMC9108303 DOI: 10.1111/eva.13368] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 02/11/2022] [Accepted: 02/17/2022] [Indexed: 11/28/2022] Open
Abstract
Males and females are often subject to different and even opposing selection pressures. When a given trait has a shared genetic basis between the sexes, sexual conflict (antagonism) can arise. This can result in significant individual-level fitness consequences that might also affect population performance, whilst anthropogenic environmental change can further exacerbate maladaptation in one or both sexes driven by sexual antagonism. Here, we develop a genetically explicit eco-evolutionary model using an agent-based framework to explore how a population of a facultatively migratory fish species (brown trout Salmo trutta) adapts to environmental change across a range of intersex genetic correlations for migration propensity, which influence the magnitude of sexual conflict. Our modelled focal trait represents a condition threshold governing whether individuals adopt a resident or anadromous (sea migration) tactic. Anadromy affords potential size-mediated reproductive advantages to both males and females due to improved feeding opportunities at sea, but these can be undermined by high background marine mortality and survival/growth costs imposed by marine parasites (sea lice). We show that migration tactic frequency for a given set of environmental conditions is strongly influenced by the intersex genetic correlation, such that one sex can be dragged off its optimum more than the other. When this occurred in females in our model, population productivity was substantially reduced, but eco-evolutionary outcomes were altered by allowing for sneaking behaviour in males. We discuss real-world implications of our work given that anadromous salmonids are regularly challenged by sea lice infestations, which might act synergistically with other stressors such as climate change or fishing that impact marine performance, driving populations towards residency and potentially reduced resilience.
Collapse
Affiliation(s)
- Adam Kane
- School of Biology and Environmental Science and Earth InstituteUniversity College DublinDublinIreland
| | - Daniel Ayllón
- Faculty of BiologyDepartment of Biodiversity, Ecology and EvolutionComplutense University of Madrid (UCM)MadridSpain
| | - Ronan James O’Sullivan
- Organismal and Evolutionary Biology Research ProgrammeFaculty of Biological and Environmental SciencesUniversity of HelsinkiHelsinkiFinland
- School of Biological, Earth and Environmental SciencesUniversity College CorkCorkIreland
- Environmental Research InstituteUniversity College CorkCorkIreland
| | - Philip McGinnity
- School of Biological, Earth and Environmental SciencesUniversity College CorkCorkIreland
- Environmental Research InstituteUniversity College CorkCorkIreland
- Marine InstituteFurnaceNewportIreland
| | - Thomas Eric Reed
- School of Biological, Earth and Environmental SciencesUniversity College CorkCorkIreland
- Environmental Research InstituteUniversity College CorkCorkIreland
| |
Collapse
|
7
|
Olito C, Vries CD. The demographic costs of sexually antagonistic selection in partially selfing populations. Am Nat 2022; 200:401-418. [DOI: 10.1086/720419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
|
8
|
Hangartner S, Sgrò CM, Connallon T, Booksmythe I. Sexual dimorphism in phenotypic plasticity and persistence under environmental change: An extension of theory and meta-analysis of current data. Ecol Lett 2022; 25:1550-1565. [PMID: 35334155 PMCID: PMC9311083 DOI: 10.1111/ele.14005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Revised: 12/18/2021] [Accepted: 03/03/2022] [Indexed: 11/29/2022]
Abstract
Populations must adapt to environmental changes to remain viable. Both evolution and phenotypic plasticity contribute to adaptation, with plasticity possibly being more important for coping with rapid change. Adaptation is complex in species with separate sexes, as the sexes can differ in the strength or direction of natural selection, the genetic basis of trait variation, and phenotypic plasticity. Many species show sex differences in plasticity, yet how these differences influence extinction susceptibility remains unclear. We first extend theoretical models of population persistence in changing environments and show that persistence is affected by sexual dimorphism for phenotypic plasticity, trait genetic architecture, and sex-specific selection. Our models predict that female-biased adaptive plasticity-particularly in traits with modest-to-low cross-sex genetic correlations-typically promotes persistence, though we also identify conditions where sexually monomorphic or male-biased plasticity promotes persistence. We then perform a meta-analysis of sex-specific plasticity under manipulated thermal conditions. Although examples of sexually dimorphic plasticity are widely observed, systematic sex differences are rare. An exception-cold resistance-is systematically female-biased and represents a trait wherein sexually dimorphic plasticity might elevate population viability in changing environments. We discuss our results in light of debates about the roles of evolution and plasticity in extinction susceptibility.
Collapse
Affiliation(s)
- Sandra Hangartner
- School of Biological Sciences, Monash University, Clayton, Victoria, Australia
| | - Carla M Sgrò
- School of Biological Sciences, Monash University, Clayton, Victoria, Australia
| | - Tim Connallon
- School of Biological Sciences, Monash University, Clayton, Victoria, Australia
| | - Isobel Booksmythe
- School of Biological Sciences, Monash University, Clayton, Victoria, Australia
| |
Collapse
|
9
|
Kokko H. The stagnation paradox: the ever-improving but (more or less) stationary population fitness. Proc Biol Sci 2021; 288:20212145. [PMID: 34784767 PMCID: PMC8596016 DOI: 10.1098/rspb.2021.2145] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Fisher's fundamental theorem states that natural selection improves mean fitness. Fitness, in turn, is often equated with population growth. This leads to an absurd prediction that life evolves to ever-faster growth rates, yet no one seriously claims generally slower population growth rates in the Triassic compared with the present day. I review here, using non-technical language, how fitness can improve yet stay constant (stagnation paradox), and why an unambiguous measure of population fitness does not exist. Subfields use different terminology for aspects of the paradox, referring to stasis, cryptic evolution or the difficulty of choosing an appropriate fitness measure; known resolutions likewise use diverse terms from environmental feedback to density dependence and ‘evolutionary environmental deterioration’. The paradox vanishes when these concepts are understood, and adaptation can lead to declining reproductive output of a population when individuals can improve their fitness by exploiting conspecifics. This is particularly readily observable when males participate in a zero-sum game over paternity and population output depends more strongly on female than male fitness. Even so, the jury is still out regarding the effect of sexual conflict on population fitness. Finally, life-history theory and genetic studies of microevolutionary change could pay more attention to each other.
Collapse
Affiliation(s)
- Hanna Kokko
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
| |
Collapse
|
10
|
Hitchcock TJ, Gardner A, Ross L. Sexual antagonism in haplodiploids. Evolution 2021; 76:292-309. [PMID: 34773705 DOI: 10.1111/evo.14398] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 09/13/2021] [Accepted: 09/27/2021] [Indexed: 11/29/2022]
Abstract
Females and males may face different selection pressures, such that alleles conferring a benefit in one sex may be deleterious in the other. Such sexual antagonism has received a great deal of theoretical and empirical attention, almost all of which has focused on diploids. However, a sizeable minority of animals display an alternative haplodiploid mode of inheritance, encompassing both arrhenotoky, whereby males develop from unfertilized eggs, and paternal genome elimination (PGE), whereby males receive but do not transmit a paternal genome. Alongside unusual genetics, haplodiploids often exhibit social ecologies that modulate the relative value of females and males. Here we develop a series of evolutionary-genetic models of sexual antagonism for haplodiploids, incorporating details of their molecular biology and social ecology. We find that: 1) PGE promotes female-beneficial alleles more than arrhenotoky, and to an extent determined by the timing of elimination - and degree of silencing of - the paternal genome; 2) sib-mating relatively promotes female-beneficial alleles, as do other forms of inbreeding, including limited male-dispersal, oedipal-mating, and the pseudo-hermaphroditism of Icerya purchasi; 3) resource competition between related females inhibits the invasion of female-beneficial alleles; and 4) sexual antagonism foments conflicts between parents and offspring, endosymbionts and hosts, and maternal-origin and paternal-origin genes. This article is protected by copyright. All rights reserved.
Collapse
Affiliation(s)
| | - Andy Gardner
- School of Biology, University of St Andrews, St Andrews, UK
| | - Laura Ross
- School of Biological Sciences, Institute of Evolutionary Biology, University of Edinburgh, Edinburgh, UK
| |
Collapse
|
11
|
Plesnar‐Bielak A, Łukasiewicz A. Sexual conflict in a changing environment. Biol Rev Camb Philos Soc 2021; 96:1854-1867. [PMID: 33960630 PMCID: PMC8518779 DOI: 10.1111/brv.12728] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 04/14/2021] [Accepted: 04/16/2021] [Indexed: 01/02/2023]
Abstract
Sexual conflict has extremely important consequences for various evolutionary processes including its effect on local adaptation and extinction probability during environmental change. The awareness that the intensity and dynamics of sexual conflict is highly dependent on the ecological setting of a population has grown in recent years, but much work is yet to be done. Here, we review progress in our understanding of the ecology of sexual conflict and how the environmental sensitivity of such conflict feeds back into population adaptivity and demography, which, in turn, determine a population's chances of surviving a sudden environmental change. We link two possible forms of sexual conflict - intralocus and interlocus sexual conflict - in an environmental context and identify major gaps in our knowledge. These include sexual conflict responses to fluctuating and oscillating environmental changes and its influence on the interplay between interlocus and intralocus sexual conflict, among others. We also highlight the need to move our investigations into more natural settings and to investigate sexual conflict dynamics in wild populations.
Collapse
Affiliation(s)
- Agata Plesnar‐Bielak
- Institute of Environmental Sciences, Faculty of BiologyJagiellonian Universityul. Gronostajowa 730‐387KrakówPoland
| | - Aleksandra Łukasiewicz
- Department of Environmental and Biological SciencesUniversity of Eastern FinlandPO Box 11180101JoensuuFinland
- Evolutionary Biology Group, Faculty of BiologyAdam Mickiewicz Universityul. Uniwersytetu Poznańskiego 661‐614PoznańPoland
| |
Collapse
|
12
|
Hector TE, Sgrò CM, Hall MD. Thermal limits in the face of infectious disease: How important are pathogens? GLOBAL CHANGE BIOLOGY 2021; 27:4469-4480. [PMID: 34170603 DOI: 10.1111/gcb.15761] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 06/14/2021] [Accepted: 06/18/2021] [Indexed: 06/13/2023]
Abstract
The frequency and severity of both extreme thermal events and disease outbreaks are predicted to continue to shift as a consequence of global change. As a result, species persistence will likely be increasingly dependent on the interaction between thermal stress and pathogen exposure. Missing from the intersection between studies of infectious disease and thermal ecology, however, is the capacity for pathogen exposure to directly disrupt a host's ability to cope with thermal stress. Common sources of variation in host thermal performance, which are likely to interact with infection, are also often unaccounted for when assessing either the vulnerability of species or the potential for disease spread during extreme thermal events. Here, we describe how infection can directly alter host thermal limits, to a degree that exceeds the level of variation commonly seen across species large geographic distributions and that equals the detrimental impact of other ecologically relevant stressors. We then discuss various sources of heterogeneity within and between populations that are likely to be important in mediating the impact that infection has on variation in host thermal limits. In doing so we highlight how infection is a widespread and important source of variation in host thermal performance, which will have implications for both the persistence and vulnerability of species and the dynamics and transmission of disease in a more thermally extreme world.
Collapse
Affiliation(s)
- Tobias E Hector
- School of Biological Sciences, Monash University, Melbourne, Vic., Australia
| | - Carla M Sgrò
- School of Biological Sciences, Monash University, Melbourne, Vic., Australia
| | - Matthew D Hall
- School of Biological Sciences, Monash University, Melbourne, Vic., Australia
- Centre of Geometric Biology, Monash University, Melbourne, Vic., Australia
| |
Collapse
|
13
|
St Leger RJ. Insects and their pathogens in a changing climate. J Invertebr Pathol 2021; 184:107644. [PMID: 34237297 DOI: 10.1016/j.jip.2021.107644] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2020] [Revised: 01/02/2021] [Accepted: 06/28/2021] [Indexed: 11/19/2022]
Abstract
The complex nature of climate change-mediated multitrophic interaction is an underexplored area, but has the potential to dramatically shift transmission and distribution of many insects and their pathogens, placing some populations closer to the brink of extinction. However, for individual insect-pathogen interactions climate change will have complicated hard-to-anticipate impacts. Thus, both pathogen virulence and insect host immunity are intrinsically linked with generalized stress responses, and in both pathogen and host have extensive trade-offs with nutrition (e.g., host plant quality), growth and reproduction. Potentially alleviating or exasperating these impacts, some pathogens and hosts respond genetically and rapidly to environmental shifts. This review identifies many areas for future research including a particular need to identify how altered global warming interacts with other environmental changes and stressors, and how consistent these impacts are across pathogens and hosts. With that achieved we would be closer to producing an overarching framework to integrate knowledge on all environmental interplay and infectious disease events.
Collapse
Affiliation(s)
- Raymond J St Leger
- Department of Entomology, University of Maryland, College Park, MD 20742, USA.
| |
Collapse
|
14
|
Schwanz LE, Georges A. Sexual Development and the Environment: Conclusions from 40 Years of Theory. Sex Dev 2021; 15:7-22. [PMID: 34130303 DOI: 10.1159/000515221] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Accepted: 01/29/2021] [Indexed: 11/19/2022] Open
Abstract
In this review, we consider the insight that has been gained through theoretical examination of environmental sex determination (ESD) and thermolability - how theory has progressed our understanding of the ecological and evolutionary dynamics associated with ESD, the transitional pathways between different modes of sex determination, and the underlying mechanisms. Following decades of theory on the adaptive benefits of ESD, several hypotheses seem promising. These hypotheses focus on the importance of differential fitness (sex-specific effects of temperature on fitness) in generating selection for ESD, but highlight alternative ways differential fitness arises: seasonal impacts on growth, sex-specific ages of maturation, and sex-biased dispersal. ESD has the potential to generate biased sex ratios quite easily, leading to complex feedbacks between the ecology and evolution of ESD. Frequency-dependent selection on sex acts on ESD-related traits, driving local adaptation or plasticity to restore equilibrium sex ratio. However, migration and overlapping generations ("mixing") diminish local adaptation and leave each cohort/population with the potential for biased sex ratios. Incorporating mechanism into ecology and evolution models reveals similarities between different sex-determining systems. Dosage and gene regulatory network models of sexual development are beginning to shed light on how temperature sensitivity and thresholds may arise. The unavoidable temperature sensitivity in sex-determining systems inherent to these models suggests that evolutionary transitions between genotypic sex determination (GSD) and temperature-dependent sex determination, and between different forms of GSD, are simple and elegant. Theoretical models are often best-served by considering a single piece of a puzzle; however, there is much to gain from reflecting on all of the pieces together in one integrative picture.
Collapse
Affiliation(s)
- Lisa E Schwanz
- Evolution and Ecology Research Centre, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, New South Wales, Australia
| | - Arthur Georges
- Institute for Applied Ecology, University of Canberra, Canberra, Australian Capital Territory, Australia
| |
Collapse
|
15
|
Flintham EO, Savolainen V, Mullon C. Dispersal Alters the Nature and Scope of Sexually Antagonistic Variation. Am Nat 2021; 197:543-559. [PMID: 33908829 DOI: 10.1086/713739] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
AbstractIntralocus sexual conflict, or sexual antagonism, occurs when alleles have opposing fitness effects in the two sexes. Previous theory suggests that sexual antagonism is a driver of genetic variation by generating balancing selection. However, most of these studies assume that populations are well mixed, neglecting the effects of spatial subdivision. Here, we use mathematical modeling to show that limited dispersal changes evolution at sexually antagonistic autosomal and X-linked loci as a result of inbreeding and sex-specific kin competition. We find that if the sexes disperse at different rates, kin competition within the philopatric sex biases intralocus conflict in favor of the more dispersive sex. Furthermore, kin competition diminishes the strength of balancing selection relative to genetic drift, reducing genetic variation in small subdivided populations. Meanwhile, by decreasing heterozygosity, inbreeding reduces the scope for sexually antagonistic polymorphism due to nonadditive allelic effects, and this occurs to a greater extent on the X chromosome than autosomes. Overall, our results indicate that spatial structure is a relevant factor in predicting where sexually antagonistic alleles might be observed. We suggest that sex-specific dispersal ecology and demography can contribute to interspecific and intragenomic variation in sexual antagonism.
Collapse
|
16
|
Dudaniec RY, Carey AR, Svensson EI, Hansson B, Yong CJ, Lancaster LT. Latitudinal clines in sexual selection, sexual size dimorphism and sex-specific genetic dispersal during a poleward range expansion. J Anim Ecol 2021; 91:1104-1118. [PMID: 33759189 DOI: 10.1111/1365-2656.13488] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Accepted: 03/09/2021] [Indexed: 10/21/2022]
Abstract
Range expansions can be shaped by sex differences in behaviours and other phenotypic traits affecting dispersal and reproduction. Here, we investigate sex differences in morphology, behaviour and genomic population differentiation along a climate-mediated range expansion in the common bluetail damselfly (Ischnura elegans) in northern Europe. We sampled 65 sites along a 583-km gradient spanning the I. elegans range in Sweden and quantified latitudinal gradients in site relative abundance, sex ratio and sex-specific shifts in body size and mating status (a measure of sexual selection). Using single nucleotide polymorphism (SNP) data for 426 individuals from 25 sites, we further investigated sex-specific landscape and climatic effects on neutral genetic connectivity and migration patterns. We found evidence for sex differences associated with the I. elegans range expansion, namely (a) increased male body size with latitude, but no latitudinal effect on female body size, resulting in reduced sexual dimorphism towards the range limit, (b) a steeper decline in male genetic similarity with increasing geographic distance than in females, (c) male-biased genetic migration propensity and (d) a latitudinal cline in migration distance (increasing migratory distances towards the range margin), which was stronger in males. Cooler mean annual temperatures towards the range limit were associated with increased resistance to gene flow in both sexes. Sex ratios became increasingly male biased towards the range limit, and there was evidence for a changed sexual selection regime shifting from favouring larger males in the south to favouring smaller males in the north. Our findings suggest sex-specific spatial phenotype sorting at the range limit, where larger males disperse more under higher landscape resistance associated with cooler climates. The combination of latitudinal gradients in sex-biased dispersal, increasing male body size and (reduced) sexual size dimorphism should have emergent consequences for sexual selection dynamics and the mating system at the expanding range front. Our study illustrates the importance of considering sex differences in the study of range expansions driven by ongoing climate change.
Collapse
Affiliation(s)
- Rachael Y Dudaniec
- Department of Biological Sciences, Macquarie University, Sydney, NSW, Australia
| | - Alexander R Carey
- Department of Biological Sciences, Macquarie University, Sydney, NSW, Australia.,Department of Planning, Industry and Environment, Saving our Species Program, New South Wales Government, Sydney, NSW, Australia
| | | | - Bengt Hansson
- Department of Biology, Lund University, Lund, Sweden
| | - Chuan Ji Yong
- Department of Biological Sciences, Macquarie University, Sydney, NSW, Australia
| | - Lesley T Lancaster
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, UK
| |
Collapse
|
17
|
Crowley PH, Labonne J. Theory of environmental sex determination: Trending populations in stressful environments. Evolution 2021; 75:794-805. [PMID: 33492683 DOI: 10.1111/evo.14176] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Revised: 01/05/2021] [Accepted: 01/13/2021] [Indexed: 11/26/2022]
Abstract
Species that have sex determined by environmental conditions during development (i.e., environmental sex determination [ESD]) are especially vulnerable to environmental change, including altered stress levels, habitat loss, and species translocations. These factors can produce multigenerational trends in population size and eco-evolutionary dynamics not captured by existing theory based on lifetime reproductive success (R0 ). Here, we extend ESD theory to use per capita growth rate r as a more appropriate measure of evolutionary success (fitness), and we demonstrate the importance of this change when males and females can differ in maturation times and when maturation times vary with local conditions (plasticity). In these cases, we show that primary and secondary sex ratios may be strongly biased; that optimal maturation times, when locally plastic, depend on the balance between mortality and growth effects; and that plasticity of maturation times can ameliorate fitness costs of increasing environmental stress.
Collapse
Affiliation(s)
- Philip H Crowley
- Department of Biology, University of Kentucky, Lexington, Kentucky, 40506.,ECOBIOP Université de Pau et des Pays de l'Adour, E2S UPPA, INRAE, ECOBIOP, Saint-Pée-sur-Nivelle, France
| | - Jacques Labonne
- ECOBIOP Université de Pau et des Pays de l'Adour, E2S UPPA, INRAE, ECOBIOP, Saint-Pée-sur-Nivelle, France
| |
Collapse
|
18
|
Evolutionary and demographic consequences of temperature-induced masculinization under climate warming: the effects of mate choice. BMC Ecol Evol 2021; 21:16. [PMID: 33541263 PMCID: PMC7860201 DOI: 10.1186/s12862-021-01747-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Accepted: 01/14/2021] [Indexed: 01/01/2023] Open
Abstract
Background One of the dangers of global climate change to wildlife is distorting sex ratios by temperature-induced sex reversals in populations where sex determination is not exclusively genetic, potentially leading to population collapse and/or sex-determination system transformation. Here we introduce a new concept on how these outcomes may be altered by mate choice if sex-chromosome-linked phenotypic traits allow females to choose between normal and sex-reversed (genetically female) males. Results We developed a theoretical model to investigate if an already existing autosomal allele encoding preference for sex-reversed males would spread and affect demographic and evolutionary processes under climate warming. We found that preference for sex-reversed males (1) more likely spread in ZW/ZZ than in XX/XY sex-determination systems, (2) in populations starting with ZW/ZZ system, it significantly hastened the transitions between different sex-determination systems and maintained more balanced adult sex ratio for longer compared to populations where all females preferred normal males; and (3) in ZW/ZZ systems with low but non-zero viability of WW individuals, a widespread preference for sex-reversed males saved the populations from early extinction. Conclusions Our results suggest that climate change may affect the evolution of mate choice, which in turn may influence the evolution of sex-determination systems, sex ratios, and thereby adaptive potential and population persistence. These findings show that preferences for sex-linked traits have special implications in species with sex reversal, highlighting the need for empirical research on the role of sex reversal in mate choice.
Collapse
|
19
|
Mautz BS, Lind MI, Maklakov AA. Dietary Restriction Improves Fitness of Aging Parents But Reduces Fitness of Their Offspring in Nematodes. J Gerontol A Biol Sci Med Sci 2021; 75:843-848. [PMID: 31761926 PMCID: PMC7164528 DOI: 10.1093/gerona/glz276] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Indexed: 11/14/2022] Open
Abstract
Dietary restriction (DR) is a well-established intervention to extend lifespan across taxa. Recent studies suggest that DR-driven lifespan extension can be cost-free, calling into question a central tenant of the evolutionary theory of aging. Nevertheless, boosting parental longevity can reduce offspring fitness. Such intergenerational trade-offs are often ignored but can account for the "missing costs" of longevity. Here, we use the nematode Caenorhabditis remanei to test for effects of DR by fasting on fitness of females and their offspring. Females deprived of food for 6 days indeed had increased fecundity, survival, and stress resistance after re-exposure to food compared with their counterparts with constant food access. However, offspring of DR mothers had reduced early and lifetime fecundity, slower growth rate, and smaller body size at sexual maturity. These findings support the direct trade-off between investment in soma and gametes challenging the hypothesis that increased somatic maintenance and impaired reproduction can be decoupled.
Collapse
Affiliation(s)
- Brian S Mautz
- Department of Ecology and Genetics, Animal Ecology, Uppsala University, Norbyvägen, Sweden.,Department of Medicine, Division of Epidemiology, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Martin I Lind
- Department of Ecology and Genetics, Animal Ecology, Uppsala University, Norbyvägen, Sweden
| | - Alexei A Maklakov
- Department of Ecology and Genetics, Animal Ecology, Uppsala University, Norbyvägen, Sweden.,School of Biological Sciences, University of East Anglia, Norwich Research Park, Norfolk, UK
| |
Collapse
|
20
|
Kyogoku D, Sota T. Sexual selection increased offspring production via evolution of male and female traits. J Evol Biol 2020; 34:501-511. [PMID: 33314378 DOI: 10.1111/jeb.13753] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 11/06/2020] [Accepted: 11/22/2020] [Indexed: 11/28/2022]
Abstract
Phenotypic evolution driven by sexual selection can impact the fitness of individuals and thus population performance through multiple mechanisms, but it is unresolved how and when sexual selection affects offspring production by females. We examined the effects of sexual selection on offspring production by females using replicated experimental evolutionary lines of Callosobruchus chinensis that were kept under polygamy (with sexual selection) or monogamy (without sexual selection) for 21 generations. We found that polygamous-line pairs produced more offspring than monogamous-line pairs, because polygamous-line beetles evolved to be larger than monogamous-line beetles, and larger females were more fecund. Egg hatchability did not differ between polygamous- and monogamous-line pairs, as a result of the positive and negative effects of sexual selection cancelling out. When mated with an individual from a common tester line, both polygamous-line females and males showed higher hatchability in resultant eggs than monogamous ones. Further, cohabitation with a male reduced egg hatchability, and this effect was more pronounced in polygamous-line than in monogamous-line males. These results demonstrate multiple mechanisms by which sexual selection affects female fitness, with the net effect being positive. Analyses of how development time, body size and male genital morphology were influenced by selection regime suggest that these results arose from both evolution via good-gene processes and sexually antagonistic selection. Our results are also consistent with the hypothesis that the fitness consequences of sexual selection for females are dependent on the evolutionary history of the population.
Collapse
Affiliation(s)
- Daisuke Kyogoku
- Ecological Integration, Graduate School of Life Sciences, Tohoku University, Sendai, Japan.,Department of Zoology, Graduate School of Science, Kyoto University, Kyoto, Japan
| | - Teiji Sota
- Department of Zoology, Graduate School of Science, Kyoto University, Kyoto, Japan
| |
Collapse
|
21
|
Laidlaw T, Hector TE, Sgrò CM, Hall MD. Pathogen exposure reduces sexual dimorphism in a host's upper thermal limits. Ecol Evol 2020; 10:12851-12859. [PMID: 33304498 PMCID: PMC7713950 DOI: 10.1002/ece3.6828] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 09/01/2020] [Accepted: 09/02/2020] [Indexed: 12/14/2022] Open
Abstract
The climate is warming at an unprecedented rate, pushing many species toward and beyond the upper temperatures at which they can survive. Global change is also leading to dramatic shifts in the distribution of pathogens. As a result, upper thermal limits and susceptibility to infection should be key determinants of whether populations continue to persist, or instead go extinct. Within a population, however, individuals vary in both their resistance to both heat stress and infection, and their contributions to vital growth rates. No more so is this true than for males and females. Each sex often varies in their response to pathogen exposure, thermal tolerances, and particularly their influence on population growth, owing to the higher parental investment that females typically make in their offspring. To date, the interplay between host sex, infection, and upper thermal limits has been neglected. Here, we explore the response of male and female Daphnia to bacterial infection and static heat stress. We find that female Daphnia, when uninfected, are much more resistant to static heat stress than males, but that infection negates any advantage that females are afforded. We discuss how the capacity of a population to cope with multiple stressors may be underestimated unless both sexes are considered simultaneously.
Collapse
Affiliation(s)
- Tess Laidlaw
- School of Biological Sciences and Centre for Geometric BiologyMonash UniversityMelbourneVic.Australia
| | - Tobias E. Hector
- School of Biological Sciences and Centre for Geometric BiologyMonash UniversityMelbourneVic.Australia
| | - Carla M. Sgrò
- School of Biological Sciences and Centre for Geometric BiologyMonash UniversityMelbourneVic.Australia
| | - Matthew D. Hall
- School of Biological Sciences and Centre for Geometric BiologyMonash UniversityMelbourneVic.Australia
| |
Collapse
|
22
|
Abstract
Climate change affects organisms worldwide with profound ecological and evolutionary consequences, often increasing population extinction risk. Climatic factors can increase the strength, variability, or direction of natural selection on phenotypic traits, potentially driving adaptive evolution. Phenotypic plasticity in relation to temperature can allow organisms to maintain fitness in response to increasing temperatures, thereby "buying time" for subsequent genetic adaptation and promoting evolutionary rescue. Although many studies have shown that organisms respond plastically to increasing temperatures, it is unclear if such thermal plasticity is adaptive. Moreover, we know little about how natural and sexual selection operate on thermal reaction norms, reflecting such plasticity. Here, we investigate how natural and sexual selection shape phenotypic plasticity in two congeneric and phenotypically similar sympatric insect species. We show that the thermal optima for longevity and mating success differ, suggesting temperature-dependent trade-offs between survival and reproduction in both sexes. Males in these species have similar thermal reaction norm slopes but have diverged in baseline body temperature (intercepts), being higher for the more northern species. Natural selection favored reduced thermal reaction norm slopes at high ambient temperatures, suggesting that the current level of thermal plasticity is maladaptive in the context of anthropogenic climate change and that selection now promotes thermal canalization and robustness. Our results show that ectothermic animals also at high latitudes can suffer from overheating and challenge the common view of phenotypic plasticity as being beneficial in harsh and novel environments.
Collapse
|
23
|
Gómez-Llano M, Narasimhan A, Svensson EI. Male-Male Competition Causes Parasite-Mediated Sexual Selection for Local Adaptation. Am Nat 2020; 196:344-354. [DOI: 10.1086/710039] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
|
24
|
Cornejo-Páramo P, Lira-Noriega A, Ramírez-Suástegui C, Méndez-de-la-Cruz FR, Székely T, Urrutia AO, Cortez D. Sex determination systems in reptiles are related to ambient temperature but not to the level of climatic fluctuation. BMC Evol Biol 2020; 20:103. [PMID: 32807071 PMCID: PMC7433102 DOI: 10.1186/s12862-020-01671-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Accepted: 08/11/2020] [Indexed: 12/19/2022] Open
Abstract
Background Vertebrates exhibit diverse sex determination systems and reptiles stand out by having highly variable sex determinations that include temperature-dependent and genotypic sex determination (TSD and GSD, respectively). Theory predicts that populations living in either highly variable or cold climatic conditions should evolve genotypic sex determination to buffer the populations from extreme sex ratios, yet these fundamental predictions have not been tested across a wide range of taxa. Results Here, we use phylogenetic analyses of 213 reptile species representing 38 families (TSD = 101 species, GSD = 112 species) and climatic data to compare breeding environments between reptiles with GSD versus TSD. We show that GSD and TSD are confronted with the same level of climatic fluctuation during breeding seasons. However, TSD reptiles are significantly associated with warmer climates. We found a strong selection on the breeding season length that minimises exposure to cold and fluctuating climate. Phylogenetic path analyses comparing competing evolutionary hypotheses support that transitions in sex determination systems influenced the ambient temperature at which the species reproduces and nests. In turn, this interaction affects other variables such as the duration of the breeding season and life-history traits. Conclusions Taken together, our results challenge long-standing hypotheses about the association between sex determination and climate variability. We also show that ambient temperature is important during breeding seasons and it helps explain the effects of sex determination systems on the geographic distribution of extant reptile species.
Collapse
Affiliation(s)
- Paola Cornejo-Páramo
- Center for Genomics Sciences, UNAM, CP62210, Cuernavaca, Mexico.,Milner Centre for Evolution, Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath, BA2 7AY, UK
| | - Andrés Lira-Noriega
- CONACYT Research Fellow, Red de Estudios Moleculares Avanzados, Instituto de Ecología, A.C. Carretera antigua a Coatepec 351, Col. El Haya, Xalapa, Veracruz, Mexico
| | - Ciro Ramírez-Suástegui
- Center for Genomics Sciences, UNAM, CP62210, Cuernavaca, Mexico.,Milner Centre for Evolution, Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath, BA2 7AY, UK
| | | | - Tamás Székely
- Milner Centre for Evolution, Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath, BA2 7AY, UK.,Department of Evolutionary Zoology and Human Biology, University of Debrecen, Debrecen, H-4032, Hungary
| | - Araxi O Urrutia
- Milner Centre for Evolution, Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath, BA2 7AY, UK. .,Institute of Ecology, UNAM, 04510, Mexico City, Mexico.
| | - Diego Cortez
- Center for Genomics Sciences, UNAM, CP62210, Cuernavaca, Mexico.
| |
Collapse
|
25
|
Abstract
Females and males may face different selection pressures. Accordingly, alleles that confer a benefit for one sex often incur a cost for the other. Classic evolutionary theory holds that the X chromosome, whose sex-biased transmission sees it spending more time in females, should value females more than males, whereas autosomes, whose transmission is unbiased, should value both sexes equally. However, recent mathematical and empirical studies indicate that male-beneficial alleles may be more favoured by the X chromosome than by autosomes. Here we develop a gene's-eye-view approach that reconciles the classic view with these recent discordant results, by separating a gene's valuation of female versus male fitness from its ability to induce fitness effects in either sex. We use this framework to generate new comparative predictions for sexually antagonistic evolution in relation to dosage compensation, sex-specific mortality and assortative mating, revealing how molecular mechanisms, ecology and demography drive variation in masculinization versus feminization across the genome.
Collapse
Affiliation(s)
| | - Andy Gardner
- School of Biology, University of St Andrews, St Andrews KY16 9TH, UK
| |
Collapse
|
26
|
Schwanz LE, Georges A, Holleley CE, Sarre SD. Climate change, sex reversal and lability of sex‐determining systems. J Evol Biol 2020; 33:270-281. [DOI: 10.1111/jeb.13587] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 12/03/2019] [Accepted: 12/22/2019] [Indexed: 12/31/2022]
Affiliation(s)
- Lisa E. Schwanz
- Evolution & Ecology Research Centre School of Biological, Earth and Environmental Sciences UNSW Sydney Sydney NSW Australia
| | - Arthur Georges
- Institute for Applied Ecology University of Canberra Canberra ACT Australia
| | - Clare E. Holleley
- Australian National Wildlife Collection CSIRO National Research Collections Australia Canberra ACT Australia
| | - Stephen D. Sarre
- Institute for Applied Ecology University of Canberra Canberra ACT Australia
| |
Collapse
|
27
|
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]
|
28
|
Matthews G, Hangartner S, Chapple DG, Connallon T. Quantifying maladaptation during the evolution of sexual dimorphism. Proc Biol Sci 2019; 286:20191372. [PMID: 31409252 DOI: 10.1098/rspb.2019.1372] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Females and males have distinct trait optima, resulting in selection for sexual dimorphism. However, most traits have strong cross-sex genetic correlations, which constrain evolutionary divergence between the sexes and lead to protracted periods of maladaptation during the evolution of sexual dimorphism. While such constraints are thought to be costly in terms of individual and population fitness, it remains unclear how severe such costs are likely to be. Building upon classical models for the 'cost of selection' in changing environments (sensu Haldane), we derived a theoretical expression for the analogous cost of evolving sexual dimorphism; this cost is a simple function of genetic (co)variances of female and male traits and sex differences in trait optima. We then conducted a comprehensive literature search, compiled quantitative genetic data from a diverse set of traits and populations, and used them to quantify costs of sexual dimorphism in the light of our model. For roughly 90% of traits, costs of sexual dimorphism appear to be modest, and comparable to the costs of fixing one or a few beneficial substitutions. For the remaining traits (approx. 10%), sexual dimorphism appears to carry a substantial cost-potentially orders of magnitude greater than costs of selection during adaptation to environmental changes.
Collapse
Affiliation(s)
- Genevieve Matthews
- School of Biological Sciences, Monash University, Clayton, Victoria 3800, Australia
| | - Sandra Hangartner
- School of Biological Sciences, Monash University, Clayton, Victoria 3800, Australia
| | - David G Chapple
- School of Biological Sciences, Monash University, Clayton, Victoria 3800, Australia
| | - Tim Connallon
- School of Biological Sciences, Monash University, Clayton, Victoria 3800, Australia.,Centre for Geometric Biology, Monash University, Clayton, Victoria 3800, Australia
| |
Collapse
|
29
|
De Lisle SP, Goedert D, Reedy AM, Svensson EI. Climatic factors and species range position predict sexually antagonistic selection across taxa. Philos Trans R Soc Lond B Biol Sci 2019; 373:rstb.2017.0415. [PMID: 30150216 DOI: 10.1098/rstb.2017.0415] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/21/2018] [Indexed: 01/31/2023] Open
Abstract
Sex differences in selection are ubiquitous in sexually reproducing organisms. When the genetic basis of traits is shared between the sexes, such sexually antagonistic selection (SAS) creates a potential constraint on adaptive evolution. Theory and laboratory experiments suggest that environmental variation and the degree of local adaptation may all affect the frequency and intensity of SAS. Here, we capitalize on a large database of over 700 spatially or temporally replicated estimates of sex-specific phenotypic selection from wild populations, combined with data on microclimates and geographical range information. We performed a meta-analysis to test three predictions from SAS theory, that selection becomes more concordant between males and females: (1) in more stressful environments, (2) in more variable environments and (3) closer to the edge of the species' range. We find partial empirical support for all three predictions. Within-study analyses indicate SAS decreases in extreme environments, as indicated by a relationship with maximum temperature, minimum precipitation and evaporative potential (PET). Across studies, we found that the average level of SAS at high latitudes was lower, where environmental conditions are typically less stable. Finally, we found evidence for reduced SAS in populations that are far from the centre of their geographical range. However, and notably, we also found some evidence of reduced average strength of selection in these populations, which is in contrast to predictions from classical theoretical models on range limit evolution. Our results suggest that environmental lability and species range position predictably influence sex-specific selection and sexual antagonism in the wild.This article is part of the theme issue 'Linking local adaptation with the evolution of sex differences'.
Collapse
Affiliation(s)
- Stephen P De Lisle
- Evolutionary Ecology Unit, Department of Biology, Lund University, Sölvegatan 37, Lund 22362, Sweden
| | - Debora Goedert
- Department of Biological Sciences, Dartmouth College, Hanover, NH 03755, USA
| | - Aaron M Reedy
- Department of Biology, University of Virginia, Charlottesville, VA 22904, USA.,Department of Biological Sciences, Auburn University, Auburn, AL 36849, USA
| | - Erik I Svensson
- Evolutionary Ecology Unit, Department of Biology, Lund University, Sölvegatan 37, Lund 22362, Sweden
| |
Collapse
|
30
|
Runemark A, Eroukhmanoff F, Nava-Bolaños A, Hermansen JS, Meier JI. Hybridization, sex-specific genomic architecture and local adaptation. Philos Trans R Soc Lond B Biol Sci 2019; 373:rstb.2017.0419. [PMID: 30150218 DOI: 10.1098/rstb.2017.0419] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/20/2018] [Indexed: 12/19/2022] Open
Abstract
While gene flow can reduce the potential for local adaptation, hybridization may conversely provide genetic variation that increases the potential for local adaptation. Hybridization may also affect adaptation through altering sexual dimorphism and sexual conflict, but this remains largely unstudied. Here, we discuss how hybridization may affect sexual dimorphism and conflict due to differential effects of hybridization on males and females, and then how this, in turn, may affect local adaptation. First, in species with heterochromatic sexes, the lower viability of the heterogametic sex in hybrids could shift the balance in sexual conflict. Second, sex-specific inheritance of the mitochondrial genome in hybrids may lead to cytonuclear mismatches, for example, in the form of 'mother's curse', with potential consequences for sex ratio and sex-specific expression. Third, sex-biased introgression and recombination may lead to sex-specific consequences of hybridization. Fourth, transgressive segregation of sexually antagonistic alleles could increase sexual dimorphism in hybrid populations. Sexual dimorphism can reduce sexual conflict and enhance intersexual niche partitioning, increasing the fitness of hybrids. Adaptive introgression of alleles reducing sexual conflict or enhancing intersexual niche partitioning may facilitate local adaptation, and could favour the colonization of novel habitats. We review these consequences of hybridization on sex differences and local adaptation, and discuss how their prevalence and importance could be tested empirically.This article is part of the theme issue 'Linking local adaptation with the evolution of sex differences'.
Collapse
Affiliation(s)
- Anna Runemark
- Department of Biology, Lund University, 22362 Lund, Sweden
| | - Fabrice Eroukhmanoff
- Centre for Ecological and Evolutionary Synthesis, University of Oslo, 0316 Oslo, Norway
| | - Angela Nava-Bolaños
- Departamento de Ecología Evolutiva, Instituto de Ecología, Universidad Nacional Autónoma de México, Apdo. Postal 70-275, Ciudad Universitaria, 04510 Ciudad de México, México
| | - Jo S Hermansen
- Centre for Ecological and Evolutionary Synthesis, University of Oslo, 0316 Oslo, Norway
| | - Joana I Meier
- Institute of Ecology and Evolution, University of Bern, 3012 Bern, Switzerland.,Department of Fish Ecology and Evolution, EAWAG, 6047 Kastanienbaum, Switzerland
| |
Collapse
|
31
|
Svensson EI, Goedert D, Gómez-Llano MA, Spagopoulou F, Nava-Bolaños A, Booksmythe I. Sex differences in local adaptation: what can we learn from reciprocal transplant experiments? Philos Trans R Soc Lond B Biol Sci 2019; 373:rstb.2017.0420. [PMID: 30150219 DOI: 10.1098/rstb.2017.0420] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/07/2018] [Indexed: 12/13/2022] Open
Abstract
Local adaptation is of fundamental interest to evolutionary biologists. Traditionally, local adaptation has been studied using reciprocal transplant experiments to quantify fitness differences between residents and immigrants in pairwise transplants between study populations. Previous studies have detected local adaptation in some cases, but others have shown lack of adaptation or even maladaptation. Recently, the importance of different fitness components, such as survival and fecundity, to local adaptation have been emphasized. Here, we address another neglected aspect in studies of local adaptation: sex differences. Given the ubiquity of sexual dimorphism in life histories and phenotypic traits, this neglect is surprising, but may be partly explained by differences in research traditions and terminology in the fields of local adaptation and sexual selection. Studies that investigate differences in mating success between resident and immigrants across populations tend to be framed in terms of reproductive and behavioural isolation, rather than local adaptation. We briefly review the published literature that bridges these areas and suggest that reciprocal transplant experiments could benefit from quantifying both male and female fitness components. Such a more integrative research approach could clarify the role of sex differences in the evolution of local adaptations.This article is part of the theme issue 'Linking local adaptation with the evolution of sex differences'.
Collapse
Affiliation(s)
| | - Debora Goedert
- Department of Biological Sciences, Dartmouth College, Hanover, NH 03755, USA
| | | | - Foteini Spagopoulou
- Animal Ecology, Department of Ecology and Evolution, Uppsala University, 752 36 Uppsala, Sweden
| | - Angela Nava-Bolaños
- Departamento de Ecología Evolutiva, Instituto de Ecología, Universidad Nacional Autónoma de México, Apdo. Postal 70-275, Ciudad Universitaria, 04510 Ciudad de México, México.,Secretaría de Educación Abierta y Continua, Facultad de Ciencias, Universidad Nacional Autónoma de México, Avenida Universidad 3000, C.U., 04510 Ciudad de México, México
| | - Isobel Booksmythe
- School of Biological Sciences, Monash University, 3800 Victoria, Australia
| |
Collapse
|
32
|
Connallon T, Débarre F, Li XY. Linking local adaptation with the evolution of sex differences. Philos Trans R Soc Lond B Biol Sci 2019; 373:rstb.2017.0414. [PMID: 30150215 DOI: 10.1098/rstb.2017.0414] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/28/2018] [Indexed: 01/21/2023] Open
Abstract
Many conspicuous forms of evolutionary diversity occur within species. Two prominent examples include evolutionary divergence between populations differentially adapted to their local environments (local adaptation), and divergence between females and males in response to sex differences in selection (sexual dimorphism sensu lato). These two forms of diversity have inspired vibrant research programmes, yet these fields have largely developed in isolation from one another. Nevertheless, conceptual parallels between these research traditions are striking. Opportunities for local adaptation strike a balance between local selection, which promotes divergence, and gene flow-via dispersal and interbreeding between populations-which constrains it. Sex differences are similarly constrained by fundamental features of inheritance that mimic gene flow. Offspring of each sex inherit genes from same-sex and opposite-sex parents, leading to gene flow between each differentially selected half of the population, and raising the question of how sex differences arise and are maintained. This special issue synthesizes and extends emerging research at the interface between the research traditions of local adaptation and sex differences. Each field can promote understanding of the other, and interactions between local adaptation and sex differences can generate new empirical predictions about the evolutionary consequences of selection that varies across space, time, and between the sexes.This article is part of the theme issue 'Linking local adaptation with the evolution of sex differences'.
Collapse
Affiliation(s)
- Tim Connallon
- School of Biological Sciences, Monash University, Clayton, Victoria, Australia
| | - Florence Débarre
- CNRS, UMR 7241 Centre Interdisciplinaire de Recherche en Biologie (CIRB), Collège de France, Paris, France
| | - Xiang-Yi Li
- Department of Evolutionary Biology and Environmental Studies, University of Zürich, Winterthurerstrasse 190, 8057 Zürich, Switzerland
| |
Collapse
|
33
|
Svensson EI, Connallon T. How frequency-dependent selection affects population fitness, maladaptation and evolutionary rescue. Evol Appl 2019; 12:1243-1258. [PMID: 31417612 PMCID: PMC6691226 DOI: 10.1111/eva.12714] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Revised: 08/31/2018] [Accepted: 09/12/2018] [Indexed: 01/04/2023] Open
Abstract
Frequency-dependent (FD) selection is a central process maintaining genetic variation and mediating evolution of population fitness. FD selection has attracted interest from researchers in a wide range of biological subdisciplines, including evolutionary genetics, behavioural ecology and, more recently, community ecology. However, the implications of frequency dependence for applied biological problems, particularly maladaptation, biological conservation and evolutionary rescue remain underexplored. The neglect of FD selection in conservation is particularly unfortunate. Classical theory, dating back to the 1940s, demonstrated that frequency dependence can either increase or decrease population fitness. These evolutionary consequences of FD selection are relevant to modern concerns about population persistence and the capacity of evolution to alleviate extinction risks. But exactly when should we expect FD selection to increase versus decrease absolute fitness and population growth? And how much of an impact is FD selection expected to have on population persistence versus extinction in changing environments? The answers to these questions have implications for evolutionary rescue under climate change and may inform strategies for managing threatened populations. Here, we revisit the core theory of FD selection, reviewing classical single-locus models of population genetic change and outlining short- and long-run consequences of FD selection for the evolution of population fitness. We then develop a quantitative genetic model of evolutionary rescue in a deteriorating environment, with population persistence hinging upon the evolution of a quantitative trait subject to both frequency-dependent and frequency-independent natural selection. We discuss the empirical literature pertinent to this theory, which supports key assumptions of our model. We show that FD selection can promote population persistence when it aligns with the direction of frequency-independent selection imposed by abiotic environmental conditions. However, under most scenarios of environmental change, FD selection limits a population's evolutionary responsiveness to changing conditions and narrows the rate of environmental change that is evolutionarily tolerable.
Collapse
Affiliation(s)
- Erik I. Svensson
- Evolutionary Ecology UnitDepartment of BiologyLund UniversityLundSweden
| | - Tim Connallon
- School of Biological SciencesMonash UniversityClaytonVictoriaAustralia
| |
Collapse
|
34
|
de Vries C, Caswell H. Selection in two-sex stage-structured populations: Genetics, demography, and polymorphism. Theor Popul Biol 2019; 130:160-169. [PMID: 31377383 PMCID: PMC6892267 DOI: 10.1016/j.tpb.2019.07.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 07/22/2019] [Accepted: 07/26/2019] [Indexed: 11/27/2022]
Abstract
The outcome of natural selection depends on the demographic processes of birth, death, and development. Here, we derive conditions for protected polymorphism in a population characterized by age- or stage-dependent demography with two sexes. We do so using a novel two-sex matrix population model including basic Mendelian genetics (one locus, two alleles, random mating). Selection may operate on survival, growth, or fertility, any or all of which may differ between the sexes. The model can therefore incorporate genes with arbitrary pleiotropic and sex-specific effects. Conditions for protected polymorphism are expressed in terms of the eigenvalues of the linearization of the model at the homozygote boundary equilibria. We show that in the absence of sexual dimorphism, polymorphism requires heterozygote superiority in the genotypic population growth rate. In the presence of sexual dimorphism, however, heterozygote superiority is not required; an inferior heterozygote may invade, reducing the population growth rate and even leading to extinction (so-called evolutionary suicide). Our model makes no assumptions about separation of time scales between ecological and evolutionary processes, and can thus be used to project sex×stage×genotype dynamics of eco-evolutionary processes. Empirical evidence that sexual dimorphism affects extinction risk is growing, yet sex differences are often ignored in evolutionary demography and in eco-evolutionary models. Our analysis highlights the importance of sexual dimorphism and suggests mechanisms by which an allele can be favored by selection, yet drive a population to extinction, as a result of the structure and interdependence of sex- and stage-specific processes.
Collapse
|
35
|
Cally JG, Stuart-Fox D, Holman L. Meta-analytic evidence that sexual selection improves population fitness. Nat Commun 2019; 10:2017. [PMID: 31043615 PMCID: PMC6494874 DOI: 10.1038/s41467-019-10074-7] [Citation(s) in RCA: 75] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Accepted: 04/16/2019] [Indexed: 01/12/2023] Open
Abstract
Sexual selection has manifold ecological and evolutionary consequences, making its net effect on population fitness difficult to predict. A powerful empirical test is to experimentally manipulate sexual selection and then determine how population fitness evolves. Here, we synthesise 459 effect sizes from 65 experimental evolution studies using meta-analysis. We find that sexual selection on males tends to elevate the mean and reduce the variance for many fitness traits, especially in females and in populations evolving under stressful conditions. Sexual selection had weaker effects on direct measures of population fitness such as extinction rate and proportion of viable offspring, relative to traits that are less closely linked to population fitness. Overall, we conclude that the beneficial population-level consequences of sexual selection typically outweigh the harmful ones and that the effects of sexual selection can differ between sexes and environments. We discuss the implications of these results for conservation and evolutionary biology. Sexual selection has the potential to either increase or decrease absolute fitness. Here, Cally et al. perform a meta-analysis of 65 experimental evolution studies and find that sexual selection on males tends to increase fitness, especially in females evolving under stressful conditions.
Collapse
Affiliation(s)
- Justin G Cally
- School of BioSciences, The University of Melbourne, Parkville, VIC, 3052, Australia.
| | - Devi Stuart-Fox
- School of BioSciences, The University of Melbourne, Parkville, VIC, 3052, Australia
| | - Luke Holman
- School of BioSciences, The University of Melbourne, Parkville, VIC, 3052, Australia
| |
Collapse
|
36
|
Li XY, Kokko H. Intersexual Resource Competition and the Evolution of Sex-Biased Dispersal. Front Ecol Evol 2019. [DOI: 10.3389/fevo.2019.00111] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
|
37
|
Connallon T, Sharma S, Olito C. Evolutionary Consequences of Sex-Specific Selection in Variable Environments: Four Simple Models Reveal Diverse Evolutionary Outcomes. Am Nat 2019; 193:93-105. [DOI: 10.1086/700720] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
|
38
|
Butka EG, Freedberg S. Population structure leads to male‐biased population sex ratios under environmental sex determination. Evolution 2018; 73:99-110. [DOI: 10.1111/evo.13653] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Accepted: 11/08/2018] [Indexed: 11/28/2022]
Affiliation(s)
- Emily G. Butka
- Department of BiologySt. Olaf College Northfield Minnesota 55057
| | - Steven Freedberg
- Department of BiologySt. Olaf College Northfield Minnesota 55057
| |
Collapse
|
39
|
Olito C, Abbott JK, Jordan CY. The interaction between sex-specific selection and local adaptation in species without separate sexes. Philos Trans R Soc Lond B Biol Sci 2018; 373:20170426. [PMID: 30150224 PMCID: PMC6125720 DOI: 10.1098/rstb.2017.0426] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/27/2018] [Indexed: 11/12/2022] Open
Abstract
Local adaptation in hermaphrodite species can be based on a variety of fitness components, including survival, as well as both female and male sex-functions within individuals. When selection via female and male fitness components varies spatially (e.g. due to environmental heterogeneity), local adaptation will depend, in part, on variation in selection through each fitness component, and the extent to which genetic trade-offs between sex-functions maintain genetic variation necessary for adaptation. Local adaptation will also depend on the hermaphrodite mating system because self-fertilization alters several key factors influencing selection and the maintenance of genetic variance underlying trade-offs between the sex-functions (sexually antagonistic polymorphism). As a first step to guide intuition regarding sex-specific adaptation in hermaphrodites, we develop a simple theoretical model incorporating the essential features of hermaphrodite mating and adaptation in a spatially heterogeneous environment, and explore the interaction between sex-specific selection, self-fertilization and local adaptation. Our results suggest that opportunities for sex-specific local adaptation in hermaphrodites depend strongly on the extent of self-fertilization and inbreeding depression. Using our model as a conceptual framework, we provide a broad overview of the literature on sex-specific selection and local adaptation in hermaphroditic plants and animals, emphasizing promising future directions in light of our theoretical predictions.This article is part of the theme issue 'Linking local adaptation with the evolution of sex differences'.
Collapse
Affiliation(s)
- Colin Olito
- Centre for Geometric Biology, School of Biological Sciences, Monash University, Victoria 3800, Australia
- Department of Biology, Section for Evolutionary Ecology, Lund University, Lund, Sweden
| | - Jessica K Abbott
- Department of Biology, Section for Evolutionary Ecology, Lund University, Lund, Sweden
| | - Crispin Y Jordan
- School of Biomedical Sciences, University of Edinburgh, Edinburgh, UK
| |
Collapse
|
40
|
Ponnikas S, Sigeman H, Abbott JK, Hansson B. Why Do Sex Chromosomes Stop Recombining? Trends Genet 2018; 34:492-503. [DOI: 10.1016/j.tig.2018.04.001] [Citation(s) in RCA: 84] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2017] [Revised: 03/22/2018] [Accepted: 04/02/2018] [Indexed: 01/05/2023]
|
41
|
Lasne C, Hangartner SB, Connallon T, Sgrò CM. Cross‐sex genetic correlations and the evolution of sex‐specific local adaptation: Insights from classical trait clines in
Drosophila melanogaster. Evolution 2018; 72:1317-1327. [DOI: 10.1111/evo.13494] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Accepted: 04/03/2018] [Indexed: 01/02/2023]
Affiliation(s)
- Clémentine Lasne
- School of Biological Sciences Monash University Clayton Victoria 3800 Australia
| | | | - Tim Connallon
- School of Biological Sciences Monash University Clayton Victoria 3800 Australia
| | - Carla M. Sgrò
- School of Biological Sciences Monash University Clayton Victoria 3800 Australia
| |
Collapse
|
42
|
Abbott JK, Nordén AK, Hansson B. Sex chromosome evolution: historical insights and future perspectives. Proc Biol Sci 2018; 284:rspb.2016.2806. [PMID: 28469017 PMCID: PMC5443938 DOI: 10.1098/rspb.2016.2806] [Citation(s) in RCA: 78] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Accepted: 04/04/2017] [Indexed: 12/26/2022] Open
Abstract
Many separate-sexed organisms have sex chromosomes controlling sex determination. Sex chromosomes often have reduced recombination, specialized (frequently sex-specific) gene content, dosage compensation and heteromorphic size. Research on sex determination and sex chromosome evolution has increased over the past decade and is today a very active field. However, some areas within the field have not received as much attention as others. We therefore believe that a historic overview of key findings and empirical discoveries will put current thinking into context and help us better understand where to go next. Here, we present a timeline of important conceptual and analytical models, as well as empirical studies that have advanced the field and changed our understanding of the evolution of sex chromosomes. Finally, we highlight gaps in our knowledge so far and propose some specific areas within the field that we recommend a greater focus on in the future, including the role of ecology in sex chromosome evolution and new multilocus models of sex chromosome divergence.
Collapse
Affiliation(s)
- Jessica K Abbott
- Department of Biology, Lund University, Sölvegatan 37, 223 62 Lund, Sweden
| | - Anna K Nordén
- Department of Biology, Lund University, Sölvegatan 37, 223 62 Lund, Sweden
| | - Bengt Hansson
- Department of Biology, Lund University, Sölvegatan 37, 223 62 Lund, Sweden
| |
Collapse
|
43
|
|
44
|
Moya C, Snopkowski K, Sear R. What do men want? Re-examining whether men benefit from higher fertility than is optimal for women. Philos Trans R Soc Lond B Biol Sci 2016; 371:20150149. [PMID: 27022076 DOI: 10.1098/rstb.2015.0149] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/05/2016] [Indexed: 01/04/2023] Open
Abstract
Several empirical observations suggest that when women have more autonomy over their reproductive decisions, fertility is lower. Some evolutionary theorists have interpreted this as evidence for sexual conflicts of interest, arguing that higher fertility is more adaptive for men than women. We suggest the assumptions underlying these arguments are problematic: assuming that women suffer higher costs of reproduction than men neglects the (different) costs of reproduction for men; the assumption that men can repartner is often false. We use simple models to illustrate that (i) menorwomen can prefer longer interbirth intervals (IBIs), (ii) if men can only partner with wives sequentially they may favour shorter IBIs than women, but such a strategy would only be optimal for a few men who can repartner. This suggests that an evolved universal male preference for higher fertility than women prefer is implausible and is unlikely to fully account for the empirical data. This further implies that if women have more reproductive autonomy, populations should grow, not decline. More precise theoretical explanations with clearly stated assumptions, and data that better address both ultimate fitness consequences and proximate psychological motivations, are needed to understand under which conditions sexual conflict over reproductive timing should arise.
Collapse
Affiliation(s)
- Cristina Moya
- Department of Human Evolutionary Biology, Harvard University, 11 Divinity Ave, Cambridge, MA 02138, USA
| | - Kristin Snopkowski
- Department of Anthropology, Boise State University, 1910 University Drive, Boise, ID 83725, USA
| | - Rebecca Sear
- Department of Population Health, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| |
Collapse
|
45
|
Connallon T, Hall MD. Genetic correlations and sex‐specific adaptation in changing environments. Evolution 2016; 70:2186-2198. [DOI: 10.1111/evo.13025] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Revised: 07/20/2016] [Accepted: 07/26/2016] [Indexed: 01/18/2023]
Affiliation(s)
- Tim Connallon
- School of Biological Sciences Monash University Clayton Victoria 3800 Australia
| | - Matthew D. Hall
- School of Biological Sciences Monash University Clayton Victoria 3800 Australia
| |
Collapse
|
46
|
Schwanz LE. Parental thermal environment alters offspring sex ratio and fitness in an oviparous lizard. ACTA ACUST UNITED AC 2016; 219:2349-57. [PMID: 27229475 DOI: 10.1242/jeb.139972] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Accepted: 05/23/2016] [Indexed: 01/18/2023]
Abstract
The environment experienced by parents can impact the phenotype of their offspring (parental effects), a critical component of organismal ecology and evolution in variable or changing environments. Although temperature is a central feature of the environment for ectotherms, its role in parental effects has been little explored until recently. Here, parental basking opportunity was manipulated in an oviparous lizard with temperature-dependent sex determination, the jacky dragon (Amphibolurus muricatus). Eggs were incubated at a temperature that typically produces a 50:50 sex ratio, and hatchlings were reared in a standard thermal environment. Offspring of parents in short bask conditions appeared to have better fitness outcomes in captive conditions than those of parents in long bask conditions - they had greater growth and survival as a function of their mass. In addition, the sex of offspring (male or female) depended on the interaction between parental treatment and egg mass, and treatment impacted whether sons or daughters grew larger in their first season. The interactive effects of treatment on offspring sex and growth are consistent with adaptive explanations for the existence of temperature-dependent sex determination in this species. Moreover, the greater performance recorded in short bask offspring may represent an anticipatory parental effect to aid offspring in predicted conditions of restricted thermal opportunity. Together, these responses constitute a crucial component of the population response to spatial or temporal variation in temperature.
Collapse
Affiliation(s)
- Lisa E Schwanz
- Research School of Biology, The Australian National University, Bruce, ACT 2601, Australia
| |
Collapse
|
47
|
|
48
|
Svensson EI, Runemark A, Verzijden MN, Wellenreuther M. Sex differences in developmental plasticity and canalization shape population divergence in mate preferences. Proc Biol Sci 2015; 281:rspb.2014.1636. [PMID: 25377451 DOI: 10.1098/rspb.2014.1636] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Sexual selection of high-quality mates can conflict with species recognition if traits that govern intraspecific mate preferences also influence interspecific recognition. This conflict might be resolved by developmental plasticity and learned mate preferences, which could drive preference divergence in populations that differ in local species composition. We integrate field and laboratory experiments on two calopterygid damselfly species with population genetic data to investigate how sex differences in developmental plasticity affect population divergence in the face of gene flow. Whereas male species recognition is fixed at emergence, females instead learn to recognize heterospecifics. Females are therefore more plastic in their mate preferences than males. We suggest that this results from sex differences in the balance between sexual selection for high-quality mates and selection for species recognition. As a result of these sex differences, females develop more pronounced population divergence in their mate preferences compared with males. Local ecological community context and presence of heterospecifics in combination with sex differences in plasticity and canalization therefore shape population divergence in mate preferences. As ongoing environmental change and habitat fragmentation bring formerly allopatric species into secondary contact, developmental plasticity of mate preferences in either or both sexes might facilitate coexistence and prevent local species extinction.
Collapse
Affiliation(s)
- Erik I Svensson
- Evolutionary Ecology Unit, Department of Biology, Lund University, Lund 223 62, Sweden
| | - Anna Runemark
- Evolutionary Ecology Unit, Department of Biology, Lund University, Lund 223 62, Sweden Centre for Ecological and Evolutionary Synthesis (CEES), Department of Biology, Oslo University, Oslo, Norway
| | - Machteld N Verzijden
- Evolutionary Ecology Unit, Department of Biology, Lund University, Lund 223 62, Sweden
| | - Maren Wellenreuther
- Evolutionary Ecology Unit, Department of Biology, Lund University, Lund 223 62, Sweden
| |
Collapse
|
49
|
Boyle M, Hone J, Schwanz LE, Georges A. Under what conditions do climate-driven sex ratios enhance versus diminish population persistence? Ecol Evol 2014; 4:4522-33. [PMID: 25512848 PMCID: PMC4264901 DOI: 10.1002/ece3.1316] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Revised: 10/04/2014] [Accepted: 10/13/2014] [Indexed: 11/11/2022] Open
Abstract
For many species of reptile, crucial demographic parameters such as embryonic survival and individual sex (male or female) depend on ambient temperature during incubation. While much has been made of the role of climate on offspring sex ratios in species with temperature-dependent sex determination (TSD), the impact of variable sex ratio on populations is likely to depend on how limiting male numbers are to female fecundity in female-biased populations, and whether a climatic effect on embryonic survival overwhelms or interacts with sex ratio. To examine the sensitivity of populations to these interacting factors, we developed a generalized model to explore the effects of embryonic survival, hatchling sex ratio, and the interaction between these, on population size and persistence while varying the levels of male limitation. Populations with TSD reached a greater maximum number of females compared to populations with GSD, although this was often associated with a narrower range of persistence. When survival depended on temperature, TSD populations persisted over a greater range of temperatures than GSD populations. This benefit of TSD was greatly reduced by even modest male limitation, indicating very strong importance of this largely unmeasured biologic factor. Finally, when males were not limiting, a steep relationship between sex ratio and temperature favoured population persistence across a wider range of climates compared to the shallower relationships. The opposite was true when males were limiting - shallow relationships between sex ratio and temperature allowed greater persistence. The results highlight that, if we are to predict the response of populations with TSD to climate change, it is imperative to 1) accurately quantify the extent to which male abundance limits female fecundity, and 2) measure how sex ratios and peak survival coincide over climate.
Collapse
Affiliation(s)
- Maria Boyle
- Institute for Applied Ecology, University of CanberraCanberra, ACT, 2601, Australia
| | - Jim Hone
- Institute for Applied Ecology, University of CanberraCanberra, ACT, 2601, Australia
| | - Lisa E Schwanz
- Institute for Applied Ecology, University of CanberraCanberra, ACT, 2601, Australia
- School of Biological, Earth and Environmental Sciences, University of New South WalesSydney, NSW, 2052, Australia
| | - Arthur Georges
- Institute for Applied Ecology, University of CanberraCanberra, ACT, 2601, Australia
| |
Collapse
|