1
|
Thompson KA, Brandvain Y, Coughlan JM, Delmore KE, Justen H, Linnen CR, Ortiz-Barrientos D, Rushworth CA, Schneemann H, Schumer M, Stelkens R. The Ecology of Hybrid Incompatibilities. Cold Spring Harb Perspect Biol 2024; 16:a041440. [PMID: 38151331 PMCID: PMC11368197 DOI: 10.1101/cshperspect.a041440] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2023]
Abstract
Ecologically mediated selection against hybrids, caused by hybrid phenotypes fitting poorly into available niches, is typically viewed as distinct from selection caused by epistatic Dobzhansky-Muller hybrid incompatibilities. Here, we show how selection against transgressive phenotypes in hybrids manifests as incompatibility. After outlining our logic, we summarize current approaches for studying ecology-based selection on hybrids. We then quantitatively review QTL-mapping studies and find traits differing between parent taxa are typically polygenic. Next, we describe how verbal models of selection on hybrids translate to phenotypic and genetic fitness landscapes, highlighting emerging approaches for detecting polygenic incompatibilities. Finally, in a synthesis of published data, we report that trait transgression-and thus possibly extrinsic hybrid incompatibility in hybrids-escalates with the phenotypic divergence between parents. We discuss conceptual implications and conclude that studying the ecological basis of hybrid incompatibility will facilitate new discoveries about mechanisms of speciation.
Collapse
Affiliation(s)
- Ken A Thompson
- Department of Biology, Stanford University, Stanford, California 94305, USA
- Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305, USA
| | - Yaniv Brandvain
- Department of Plant and Microbial Biology, University of Minnesota - Twin Cities, St Paul, Minnesota 55108, USA
| | - Jenn M Coughlan
- Department of Ecology & Evolutionary Biology, Yale University, New Haven, Connecticut 06511, USA
| | - Kira E Delmore
- Department of Biology, Texas A&M University, College Station, Texas 77843, USA
| | - Hannah Justen
- Department of Biology, Texas A&M University, College Station, Texas 77843, USA
| | - Catherine R Linnen
- Department of Biology, University of Kentucky, Lexington, Kentucky 40506, USA
| | - Daniel Ortiz-Barrientos
- School of Biological Sciences, The University of Queensland, Centre of Excellence for Plant Success in Nature and Agriculture, St Lucia, Queensland 4072, Australia
| | - Catherine A Rushworth
- Department of Biology and Ecology Center, Utah State University, Logan, Utah 84322, USA
| | - Hilde Schneemann
- Department of Genetics, University of Cambridge, Cambridge CB2 3EH, United Kingdom
| | - Molly Schumer
- Department of Biology, Stanford University, Stanford, California 94305, USA
- Centro de Investigaciones Científicas de las Huastecas "Aguazarca," A.C., Calnali 43240, Mexico
- Hanna H. Gray Fellow, Howard Hughes Medical Institute, Chevy Chase, Maryland 20815, USA
| | - Rike Stelkens
- Division of Population Genetics, Department of Zoology, Stockholm University, 106 91 Stockholm, Sweden
| |
Collapse
|
2
|
Dopman EB, Shaw KL, Servedio MR, Butlin RK, Smadja CM. Coupling of Barriers to Gene Exchange: Causes and Consequences. Cold Spring Harb Perspect Biol 2024; 16:a041432. [PMID: 38191516 PMCID: PMC11293547 DOI: 10.1101/cshperspect.a041432] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2024]
Abstract
Coupling has emerged as a concept to describe the transition from differentiated populations to newly evolved species through the strengthening of reproductive isolation. However, the term has been used in multiple ways, and relevant processes have sometimes not been clearly distinguished. Here, we synthesize existing uses of the concept of coupling and find three main perspectives: (1) coupling as the build-up of linkage disequilibrium among loci underlying barriers to gene exchange, (2) coupling as the build-up of genome-wide linkage disequilibrium, and (3) coupling as the process generating a coincidence of distinct barrier effects. We compare and contrast these views, show the diverse processes involved and the complexity of the relationships among recombination, linkage disequilibrium, and reproductive isolation, and, finally, we emphasize how each perspective can guide new directions in speciation research. Although the importance of coupling for evolutionary divergence and speciation is well established, many theoretical and empirical questions remain unanswered.
Collapse
Affiliation(s)
- Erik B Dopman
- Department of Biology, Tufts University, Medford, Massachusetts 02155, USA
| | - Kerry L Shaw
- Department of Neurobiology and Behavior, Cornell University, Ithaca, New York 14853, USA
| | - Maria R Servedio
- Department of Biology, University of North Carolina, Chapel Hill, North Carolina 27599, USA
| | - Roger K Butlin
- Ecology and Evolutionary Biology, School of Biosciences, The University of Sheffield, Western Bank, Sheffield S10 2TN, United Kingdom
- Department of Marine Sciences, University of Gothenburg, Gothenburg 40530, Sweden
| | - Carole M Smadja
- Institut des Sciences de l'Evolution de Montpellier ISEM, Universite de Montpellier, CNRS, IRD, Montpellier 34095, France
| |
Collapse
|
3
|
Roy PR, Castillo DM. The neurodevelopmental genes alan shepard and Neuroglian contribute to female mate preference in African Drosophila melanogaster. J Evol Biol 2024; 37:877-890. [PMID: 38900077 PMCID: PMC11292574 DOI: 10.1093/jeb/voae074] [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: 06/08/2023] [Revised: 03/07/2024] [Accepted: 06/19/2024] [Indexed: 06/21/2024]
Abstract
Mate choice is a key trait that determines fitness for most sexually reproducing organisms, with females often being the choosy sex. Female preference often results in strong selection on male traits that can drive rapid divergence of traits and preferences between lineages, leading to reproductive isolation. Despite this fundamental property of female mate choice, very few loci have been identified that contribute to mate choice and reproductive isolation. We used a combination of population genetics, quantitative complementation tests, and behavioural assays to demonstrate that alan shepard and Neuroglian contribute to female mate choice, and could contribute to partial reproductive isolation between populations of Drosophila melanogaster. Our study is among the first to identify genes that contribute to female mate preference in this historically important system, where female preference is an active premating barrier to reproduction. The identification of loci that are primarily known for their roles in neurodevelopment provides intriguing questions of how female mate preference evolves in populations via changes in sensory system and higher learning brain centres.
Collapse
Affiliation(s)
- Paula R Roy
- School of Biological Sciences, University of Utah, Salt Lake City, UT, United States
| | - Dean M Castillo
- School of Biological Sciences, University of Utah, Salt Lake City, UT, United States
| |
Collapse
|
4
|
Burban E, Tenaillon MI, Glémin S. RIDGE, a tool tailored to detect gene flow barriers across species pairs. Mol Ecol Resour 2024; 24:e13944. [PMID: 38419376 DOI: 10.1111/1755-0998.13944] [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: 09/15/2023] [Revised: 01/19/2024] [Accepted: 02/05/2024] [Indexed: 03/02/2024]
Abstract
Characterizing the processes underlying reproductive isolation between diverging lineages is central to understanding speciation. Here, we present RIDGE-Reproductive Isolation Detection using Genomic polymorphisms-a tool tailored for quantifying gene flow barrier proportion and identifying the relevant genomic regions. RIDGE relies on an Approximate Bayesian Computation with a model-averaging approach to accommodate diverse scenarios of lineage divergence. It captures heterogeneity in effective migration rate along the genome while accounting for variation in linked selection and recombination. The barrier detection test relies on numerous summary statistics to compute a Bayes factor, offering a robust statistical framework that facilitates cross-species comparisons. Simulations revealed RIDGE's efficiency in capturing signals of ongoing migration. Model averaging proved particularly valuable in scenarios of high model uncertainty where no migration or migration homogeneity can be wrongly assumed, typically for recent divergence times <0.1 2Ne generations. Applying RIDGE to four published crow data sets, we first validated our tool by identifying a well-known large genomic region associated with mate choice patterns. Second, while we identified a significant overlap of outlier loci using RIDGE and traditional genomic scans, our results suggest that a substantial portion of previously identified outliers are likely false positives. Outlier detection relies on allele differentiation, relative measures of divergence and the count of shared polymorphisms and fixed differences. Our analyses also highlight the value of incorporating multiple summary statistics including our newly developed outlier ones that can be useful in challenging detection conditions.
Collapse
Affiliation(s)
- Ewen Burban
- University of Rennes, CNRS, ECOBIO-UMR 6553, Rennes, France
| | - Maud I Tenaillon
- University Paris-Saclay, INRAE, CNRS, AgroParisTech, GQE-Le Moulon, Gif-sur-Yvette, France
| | - Sylvain Glémin
- University of Rennes, CNRS, ECOBIO-UMR 6553, Rennes, France
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
| |
Collapse
|
5
|
Merrill RM, Arenas-Castro H, Feller AF, Harenčár J, Rossi M, Streisfeld MA, Kay KM. Genetics and the Evolution of Prezygotic Isolation. Cold Spring Harb Perspect Biol 2024; 16:a041439. [PMID: 37848246 PMCID: PMC10835618 DOI: 10.1101/cshperspect.a041439] [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] [Indexed: 10/19/2023]
Abstract
The significance of prezygotic isolation for speciation has been recognized at least since the Modern Synthesis. However, fundamental questions remain. For example, how are genetic associations between traits that contribute to prezygotic isolation maintained? What is the source of genetic variation underlying the evolution of these traits? And how do prezygotic barriers affect patterns of gene flow? We address these questions by reviewing genetic features shared across plants and animals that influence prezygotic isolation. Emerging technologies increasingly enable the identification and functional characterization of the genes involved, allowing us to test established theoretical expectations. Embedding these genes in their developmental context will allow further predictions about what constrains the evolution of prezygotic isolation. Ongoing improvements in statistical and computational tools will reveal how pre- and postzygotic isolation may differ in how they influence gene flow across the genome. Finally, we highlight opportunities for progress by combining theory with appropriate data.
Collapse
Affiliation(s)
- Richard M Merrill
- Faculty of Biology, Division of Evolutionary Biology, LMU Munich, 82152 Planegg-Martinsried, Germany
| | - Henry Arenas-Castro
- School of Biological Sciences, University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Anna F Feller
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts 02138, USA
- Arnold Arboretum of Harvard University, Boston, Massachusetts 02131, USA
| | - Julia Harenčár
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, Santa Cruz, California 95060, USA
| | - Matteo Rossi
- Faculty of Biology, Division of Evolutionary Biology, LMU Munich, 82152 Planegg-Martinsried, Germany
| | - Matthew A Streisfeld
- Institute of Ecology and Evolution, University of Oregon, Eugene, Oregon 97403-5289, USA
| | - Kathleen M Kay
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, Santa Cruz, California 95060, USA
| |
Collapse
|
6
|
Corney RH, Weir LK. Does paternal care influence mate preference? Male and female mating behavior in Threespine Stickleback ecotypes that differ markedly in parental care. Ecol Evol 2023; 13:e9953. [PMID: 36998604 PMCID: PMC10049857 DOI: 10.1002/ece3.9953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 02/09/2023] [Accepted: 03/14/2023] [Indexed: 03/30/2023] Open
Abstract
Reproductive isolation can occur due to divergence in sexual selection for particular traits. For example, differences in mate preference associated with body size can play an important role in divergence between groups. The importance of mate preference for population divergence may be influenced by other aspects of a mating system, such as the requirement for parental care. In Nova Scotia, Canada, two ecotypes of marine Threespine Stickleback occur sympatrically: a "common" ecotype wherein males provide parental care, and a "white" ecotype that does not exhibit paternal care. The goal of our study was to examine differences in male mate preference between white and common stickleback males to test the prediction that males who invest more in parental care may be more selective about their mates. Because of the link between size and fecundity in this species, we predict that males that invest in parental care should prefer large females, while males that do not provide care will not exhibit preference for larger female size. We found that common male stickleback preferred larger-bodied females of both ecotypes, while white males showed a preference for larger-bodied common females. Secondarily, we assessed whether females differed in their willingness to mate with males of different sizes and ecotypes. Common female stickleback had a higher response rate toward smaller white males, which may be associated with their relatively high courtship rates. Counter to previous studies on these ecotypes that suggest that mating is completely assortative, interecotype matings occurred in half of the observed spawning events. This observation, coupled with the results that males may prefer females based mainly on size and females respond to males who court more rigorously regardless of their ecotype, may lend insight into recent genetic evidence for hybridization in the wild.
Collapse
Affiliation(s)
- Rachel H. Corney
- Department of BiologySaint Mary's UniversityHalifaxNova ScotiaCanada
| | - Laura K. Weir
- Department of BiologySaint Mary's UniversityHalifaxNova ScotiaCanada
| |
Collapse
|
7
|
Life on a beach leads to phenotypic divergence despite gene flow for an island lizard. Commun Biol 2023; 6:141. [PMID: 36732444 PMCID: PMC9895042 DOI: 10.1038/s42003-023-04494-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Accepted: 01/17/2023] [Indexed: 02/04/2023] Open
Abstract
Limited spatial separation within small islands suggests that observed population divergence may occur due to habitat differences without interruption to gene flow but strong evidence of this is scarce. The wall lizard Teira dugesii lives in starkly contrasting shingle beach and inland habitats on the island of Madeira. We used a matched pairs sampling design to examine morphological and genomic divergence between four beach and adjacent (<1 km) inland areas. Beach populations are significantly darker than corresponding inland populations. Geometric morphometric analyses reveal divergence in head morphology: beach lizards have generally wider snouts. Genotyping-by-sequencing allows the rejection of the hypothesis that beach populations form a distinct lineage. Bayesian analyses provide strong support for models that incorporate gene flow, relative to those that do not, replicated at all pairs of matched sites. Madeiran lizards show morphological divergence between habitats in the face of gene flow, revealing how divergence may originate within small islands.
Collapse
|
8
|
Schuldiner‐Harpaz T, Merrill RM, Jiggins CD. Evolution of physical linkage between loci controlling ecological traits and mating preferences. J Evol Biol 2022; 35:1537-1547. [PMID: 36196988 PMCID: PMC9827829 DOI: 10.1111/jeb.14105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Revised: 07/26/2022] [Accepted: 08/08/2022] [Indexed: 01/12/2023]
Abstract
Coupling of multiple barriers to gene-flow, such as divergent local adaptation and reproductive isolation, facilitates speciation. However, alleles at loci that contribute to barrier effects can be dissociated by recombination. Models of linkage between diverging alleles often consider elements that reduce recombination, such as chromosomal inversions and alleles that modify recombination rate between existing loci. In contrast, here, we consider the evolution of linkage due to the close proximity of loci on the same chromosome. Examples of such physical linkage exist in several species, but in other cases, strong associations are maintained without physical linkage. We use an individual-based model to study the conditions under which the physical linkage between loci controlling ecological traits and mating preferences might be expected to evolve. We modelled a single locus controlling an ecological trait that acts also as a mating cue. Mating preferences are controlled by multiple loci, formed by mutations that are randomly placed in the "genome", within varying distances from the ecological trait locus, allowing us to examine which genomic architectures spread across the population. Our model reveals that stronger physical linkage is favoured when mating preferences and selection are weaker. Under such conditions mating among divergent phenotypes is more frequent, and matching ecological trait and mating preference alleles are more likely to become dissociated by recombination, favouring the evolution of genetic linkage. While most theoretical studies on clustering of divergent loci focus on how physical linkage influences speciation, we show how physical linkage itself can arise, establishing conditions that can favour speciation.
Collapse
|
9
|
Piñeros VJ, Del R Pedraza-Marrón C, Betancourt-Resendes I, Calderón-Cortés N, Betancur-R R, Domínguez-Domínguez O. Genome-wide species delimitation analyses of a silverside fish species complex in central Mexico indicate taxonomic over-splitting. BMC Ecol Evol 2022; 22:108. [PMID: 36104671 PMCID: PMC9472351 DOI: 10.1186/s12862-022-02063-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Accepted: 09/06/2022] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND Delimiting species across a speciation continuum is a complex task, as the process of species origin is not generally instantaneous. The use of genome-wide data provides unprecedented resolution to address convoluted species delimitation cases, often unraveling cryptic diversity. However, because genome-wide approaches based on the multispecies coalescent model are known to confound population structure with species boundaries, often resulting in taxonomic over-splitting, it has become increasingly evident that species delimitation research must consider multiple lines of evidence. In this study, we used phylogenomic, population genomic, and coalescent-based species delimitation approaches, and examined those in light of morphological and ecological information, to investigate species numbers and boundaries comprising the Chirostoma "humboltianum group" (family Atherinidae). The humboltianum group is a taxonomically controversial species complex where previous morphological and mitochondrial studies produced conflicting species delimitation outcomes. We generated ddRADseq data for 77 individuals representing the nine nominal species in the group, spanning their distribution range in the central Mexican plateau. RESULTS Our results conflict with the morphospecies and ecological delimitation hypotheses, identifying four independently evolving lineages organized in three geographically cohesive clades: (i) chapalae and sphyraena groups in Lake Chapala, (ii) estor group in Lakes Pátzcuaro and Zirahuén, and (iii) humboltianum sensu stricto group in Lake Zacapu and Lerma river system. CONCLUSIONS Overall, our study provides an atypical example where genome-wide analyses delineate fewer species than previously recognized on the basis of morphology. It also highlights the influence of the geological history of the Chapala-Lerma hydrological system in driving allopatric speciation in the humboltianum group.
Collapse
Affiliation(s)
- Victor Julio Piñeros
- Laboratorio de Ecología Molecular, Escuela Nacional de Estudios Superiores Unidad Morelia, Universidad Nacional Autónoma de México, Antigua Carretera a Pátzcuaro 8701, Ex-Hacienda de San José de La Huerta, 58190, Morelia, Michoacán, Mexico
| | | | - Isaí Betancourt-Resendes
- Facultad de Ciencias Naturales, Universidad Autónoma de Querétaro, Avenida de Las Ciencias S/N Juriquilla, Delegación Santa Rosa Jáuregui, 76230, Querétaro, Mexico
| | - Nancy Calderón-Cortés
- Laboratorio de Ecología Molecular, Escuela Nacional de Estudios Superiores Unidad Morelia, Universidad Nacional Autónoma de México, Antigua Carretera a Pátzcuaro 8701, Ex-Hacienda de San José de La Huerta, 58190, Morelia, Michoacán, Mexico.
| | - Ricardo Betancur-R
- Department of Biology, The University of Oklahoma, 730 Van Vleet Oval, Norman, OK, 73019, USA
| | - Omar Domínguez-Domínguez
- Laboratorio de Biología Acuática, Facultad de Biología, Universidad Michoacana de San Nicolás de Hidalgo, Edificio "R" Planta Baja, Ciudad Universitaria, 58030, Morelia, Michoacán, Mexico.
- Laboratorio Nacional de Análisis y Síntesis Ecológica Para la Conservación de Recursos Genéticos de México, Escuela Nacional de Estudios Superiores, Unidad Morelia, Universidad Nacional Autónoma de México, Apartado Postal 27-3 (Xangari), 58089, Michoacán, Morelia, Mexico.
| |
Collapse
|
10
|
Abstract
Speciation is the process by which barriers to gene flow evolve between populations. Although we now know that speciation is largely driven by natural selection, knowledge of the agents of selection and the genetic and genomic mechanisms that facilitate divergence is required for a satisfactory theory of speciation. In this essay, we highlight three advances/problems in our understanding of speciation that have arisen from studies of the genes and genomic regions that underlie the evolution of reproductive isolation. First, we describe how the identification of “speciation” genes makes it possible to identify the agents of selection causing the evolution of reproductive isolation, while also noting that the link between the genetics of phenotypic divergence and intrinsic postzygotic reproductive barriers remains tenuous. Second, we discuss the important role of recombination suppressors in facilitating speciation with gene flow, but point out that the means and timing by which reproductive barriers become associated with recombination cold spots remains uncertain. Third, we establish the importance of ancient genetic variation in speciation, although we argue that the focus of speciation studies on evolutionarily young groups may bias conclusions in favor of ancient variation relative to new mutations.
Collapse
|
11
|
Kennedy SR, Ying Lim J, Ashley Adams S, Krehenwinkel H, Gillespie RG. What is adaptive radiation? Many manifestations of the phenomenon in an iconic lineage of Hawaiian spiders. Mol Phylogenet Evol 2022; 175:107564. [PMID: 35787456 DOI: 10.1016/j.ympev.2022.107564] [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: 03/25/2022] [Revised: 05/27/2022] [Accepted: 06/02/2022] [Indexed: 11/16/2022]
Abstract
Adaptive radiation provides the ideal context for identifying and testing the processes that drive evolutionary diversification. However, different adaptive radiations show a variety of different patterns, making it difficult to come up with universal rules that characterize all such systems. Diversification may occur via several mechanisms including non-adaptive divergence, adaptation to novel environments, or character displacement driven by competition. Here, we characterize the ways these different drivers contribute to present-day diversity patterns, using the exemplary adaptive radiation of Hawaiian long-jawed orbweaver (Tetragnatha) spiders. We present the most taxonomically comprehensive phylogenetic hypothesis to date for this group, using 10 molecular markers and representatives from every known species across the archipelago. Among the lineages that make up this remarkable radiation, we find evidence for multiple diversification modalities. Several clades appear to have diversified in allopatry under a narrow range of ecological conditions, highlighting the role of niche conservatism in speciation. Others have shifted into new environments and evolved traits that appear to be adaptive in those environments. Still others show evidence for character displacement by close relatives, often resulting in convergent evolution of stereotyped ecomorphs. All of the above mechanisms seem to have played a role in giving rise to the exceptional diversity of morphological, ecological and behavioral traits represented among the many species of Hawaiian Tetragnatha. Taking all these processes into account, and testing how they operate in different systems, may allow us to identify universal principles underlying adaptive radiation.
Collapse
Affiliation(s)
| | - Jun Ying Lim
- Department of Biological Sciences, National University of Singapore, Singapore
| | - Seira Ashley Adams
- Department of Environmental Science, Policy and Management, University of California Berkeley, USA
| | | | - Rosemary G Gillespie
- Department of Environmental Science, Policy and Management, University of California Berkeley, USA
| |
Collapse
|
12
|
Non-parallel morphological divergence following colonization of a new host plant. Evol Ecol 2022. [DOI: 10.1007/s10682-022-10189-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
AbstractAdaptation to new ecological niches is known to spur population diversification and may lead to speciation if gene flow is ceased. While adaptation to the same ecological niche is expected to be parallel, it is more difficult to predict whether selection against maladaptive hybridization in secondary sympatry results in parallel divergence also in traits that are not directly related to the ecological niches. Such parallelisms in response to selection for reproductive isolation can be identified through estimating parallelism in reproductive character displacement across different zones of secondary contact. Here, we use a host shift in the phytophagous peacock fly Tephritis conura, with both host races represented in two geographically separate areas East and West of the Baltic Sea to investigate convergence in morphological adaptations. We asked (i) if there are consistent morphological adaptations to a host plant shift and (ii) if the response to secondary sympatry with the alternate host race is parallel across contact zones. We found surprisingly low and variable, albeit significant, divergence between host races. Only one trait, the length of the female ovipositor, which serves an important function in the interaction with the hosts, was consistently different between host races. Instead, co-existence with the other host race significantly affected the degree of morphological divergence, but the divergence was largely driven by different traits in different contact zones. Thus, local stochastic fixation or reinforcement could generate trait divergence, and additional evidence is needed to conclude whether divergence is locally adaptive.
Collapse
|
13
|
Thompson KA, Schluter D. Heterosis counteracts hybrid breakdown to forestall speciation by parallel natural selection. Proc Biol Sci 2022; 289:20220422. [PMID: 35506223 PMCID: PMC9065978 DOI: 10.1098/rspb.2022.0422] [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: 03/04/2022] [Accepted: 03/30/2022] [Indexed: 01/04/2023] Open
Abstract
In contrast to ecological speciation, where reproductive isolation evolves as a consequence of divergent natural selection, speciation by parallel natural selection has been less thoroughly studied. To test whether parallel evolution drives speciation, we leveraged the repeated evolution of benthic and limnetic ecotypes of threespine stickleback fish and estimated fitness for pure crosses and within-ecotype hybrids in semi-natural ponds and in laboratory aquaria. In ponds, we detected hybrid breakdown in both ecotypes but this was counterbalanced by heterosis and the strength of post-zygotic isolation was nil. In aquaria, we detected heterosis in limnetic crosses and breakdown in benthic crosses, which is suggestive of process- and ecotype-specific environment-dependence. In ponds, heterosis and breakdown were three times greater in limnetic crosses than in benthic crosses, contrasting the prediction that the fitness consequences of hybridization should be greater in crosses among more derived ecotypes. Consistent with a primary role for stochastic processes, patterns differed among crosses between populations from different lakes. Yet, the observation of qualitatively similar patterns of heterosis and hybrid breakdown for both ecotypes when averaging the lake pairs indicates that the outcome of hybridization is repeatable in a general sense.
Collapse
Affiliation(s)
- Ken A. Thompson
- Department of Zoology and Biodiversity Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Dolph Schluter
- Department of Zoology and Biodiversity Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| |
Collapse
|
14
|
Imbalanced segregation of recombinant haplotypes in hybrid populations reveals inter- and intrachromosomal Dobzhansky-Muller incompatibilities. PLoS Genet 2022; 18:e1010120. [PMID: 35344560 PMCID: PMC8989332 DOI: 10.1371/journal.pgen.1010120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 04/07/2022] [Accepted: 02/25/2022] [Indexed: 11/19/2022] Open
Abstract
Dobzhansky-Muller incompatibilities (DMIs) are a major component of reproductive isolation between species. DMIs imply negative epistasis and are exposed when two diverged populations hybridize. Mapping the locations of DMIs has largely relied on classical genetic mapping. Approaches to date are hampered by low power and the challenge of identifying DMI loci on the same chromosome, because strong initial linkage of parental haplotypes weakens statistical tests. Here, we propose new statistics to infer negative epistasis from haplotype frequencies in hybrid populations. When two divergent populations hybridize, the variance in heterozygosity at two loci decreases faster with time at DMI loci than at random pairs of loci. When two populations hybridize at near-even admixture proportions, the deviation of the observed variance from its expectation becomes negative for the DMI pair. This negative deviation enables us to detect intermediate to strong negative epistasis both within and between chromosomes. In practice, the detection window in hybrid populations depends on the demographic scenario, the recombination rate, and the strength of epistasis. When the initial proportion of the two parental populations is uneven, only strong DMIs can be detected with our method unless migration prevents parental haplotypes from being lost. We use the new statistics to infer candidate DMIs from three hybrid populations of swordtail fish. We identify numerous new DMI candidates, some of which are inferred to interact with several loci within and between chromosomes. Moreover, we discuss our results in the context of an expected enrichment in intrachromosomal over interchromosomal DMIs.
Collapse
|
15
|
Thompson KA, Peichel CL, Rennison DJ, McGee MD, Albert AYK, Vines TH, Greenwood AK, Wark AR, Brandvain Y, Schumer M, Schluter D. Analysis of ancestry heterozygosity suggests that hybrid incompatibilities in threespine stickleback are environment dependent. PLoS Biol 2022; 20:e3001469. [PMID: 35007278 PMCID: PMC8746713 DOI: 10.1371/journal.pbio.3001469] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Accepted: 11/04/2021] [Indexed: 12/25/2022] Open
Abstract
Hybrid incompatibilities occur when interactions between opposite ancestry alleles at different loci reduce the fitness of hybrids. Most work on incompatibilities has focused on those that are "intrinsic," meaning they affect viability and sterility in the laboratory. Theory predicts that ecological selection can also underlie hybrid incompatibilities, but tests of this hypothesis using sequence data are scarce. In this article, we compiled genetic data for F2 hybrid crosses between divergent populations of threespine stickleback fish (Gasterosteus aculeatus L.) that were born and raised in either the field (seminatural experimental ponds) or the laboratory (aquaria). Because selection against incompatibilities results in elevated ancestry heterozygosity, we tested the prediction that ancestry heterozygosity will be higher in pond-raised fish compared to those raised in aquaria. We found that ancestry heterozygosity was elevated by approximately 3% in crosses raised in ponds compared to those raised in aquaria. Additional analyses support a phenotypic basis for incompatibility and suggest that environment-specific single-locus heterozygote advantage is not the cause of selection on ancestry heterozygosity. Our study provides evidence that, in stickleback, a coarse-albeit indirect-signal of environment-dependent hybrid incompatibility is reliably detectable and suggests that extrinsic incompatibilities can evolve before intrinsic incompatibilities.
Collapse
Affiliation(s)
- Ken A. Thompson
- Department of Zoology & Biodiversity Research Centre, University of British Columbia, Canada
| | - Catherine L. Peichel
- Division of Evolutionary Ecology, Institute of Ecology and Evolution, University of Bern, Bern, Switzerland
| | - Diana J. Rennison
- Division of Biological Sciences, University of California San Diego, San Diego, California, United States of America
| | - Matthew D. McGee
- School of Biological Sciences, Monash University, Melbourne, Victoria, Australia
| | | | - Timothy H. Vines
- DataSeer Research Data Services, Vancouver, British Columbia, Canada
| | | | - Abigail R. Wark
- Harvard Medical School, Cambridge, Massachusetts, United States of America
| | - Yaniv Brandvain
- Department of Plant and Microbial Biology, University of Minnesota, Saint Paul, Minnesota, United States of America
| | - Molly Schumer
- Department of Biology, Stanford University, Stanford, California, United States of America
- Howard Hughes Medical Institute, Maryland, United States of America
| | - Dolph Schluter
- Department of Zoology & Biodiversity Research Centre, University of British Columbia, Canada
| |
Collapse
|
16
|
Corney RH, Haley AL, Weir LK. Flexibility of nuptial colouration in a unique ecotype of threespine stickleback (Gasterosteus aculeatus). CAN J ZOOL 2021. [DOI: 10.1139/cjz-2021-0008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Nuptial colouration in animals may serve as a signal of competitor and (or) mate quality during breeding. In many temperate fishes, nuptial colouration develops during discrete breeding seasons and is a target of sexual selection. We examine nuptial colouration and behaviour of a unique ecotype of threespine stickleback (Gasterosteus aculeatus Linnaeus, 1758), wherein males turn from dull brown-grey to pearlescent white during the breeding season. The main goal of this work was to determine the relative role of white colouration in intersexual competition and mate choice. In a combination of field and laboratory work, we found that males are brightest white when engaging in courtship activities in the presence of a female; this indicates that white colouration may be primarily related to enhancing signalling during mate attraction. White colouration intensity increased as the breeding season progressed and may be related to an influx of conspecifics. Colour change from cryptic grey to bright white occurred rapidly (<90 s) and may be deployed to enhance behavioural signals. We conclude that bright white colouration in the white ecotype is a potential signal of mate quality and may have evolved from a previously existing capacity for colour plasticity in common threespine stickleback.
Collapse
Affiliation(s)
- Rachel H. Corney
- Biology Department, Saint Mary’s University, 923 Robie Street, Halifax, NS B3H 3C3, Canada
- Biology Department, Saint Mary’s University, 923 Robie Street, Halifax, NS B3H 3C3, Canada
| | - Anne L. Haley
- Biology Department, Saint Mary’s University, 923 Robie Street, Halifax, NS B3H 3C3, Canada
- Biology Department, Saint Mary’s University, 923 Robie Street, Halifax, NS B3H 3C3, Canada
| | - Laura K. Weir
- Biology Department, Saint Mary’s University, 923 Robie Street, Halifax, NS B3H 3C3, Canada
- Biology Department, Saint Mary’s University, 923 Robie Street, Halifax, NS B3H 3C3, Canada
| |
Collapse
|
17
|
Hausmann AE, Kuo CY, Freire M, Rueda-M N, Linares M, Pardo-Diaz C, Salazar C, Merrill RM. Light environment influences mating behaviours during the early stages of divergence in tropical butterflies. Proc Biol Sci 2021; 288:20210157. [PMID: 33757348 PMCID: PMC8059652 DOI: 10.1098/rspb.2021.0157] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 02/23/2021] [Indexed: 12/31/2022] Open
Abstract
Speciation is facilitated when traits under divergent selection also act as mating cues. Fluctuations in sensory conditions can alter signal perception independently of adaptation to the broader sensory environment, but how this fine-scale variation may constrain or promote behavioural isolation has received little attention. The warning patterns of Heliconius butterflies are under selection for aposematism and act as mating cues. Using computer vision, we extracted behavioural data from 1481 h of video footage, for 387 individuals. We show that the putative hybrid species H. heurippa and its close relative H. timareta linaresi differ in their response to divergent warning patterns, but that these differences are strengthened with increased local illuminance. Trials with live individuals reveal low-level assortative mating that is sufficiently explained by differences in visual attraction. Finally, results from hybrid butterflies are consistent with linkage between a major warning pattern gene and the corresponding behaviour, though the differences in behaviour we observe are unlikely to cause rapid reproductive isolation as predicted under a model of hybrid trait speciation. Overall, our results reveal that the contribution of ecological mating cues to reproductive isolation may depend on the immediate sensory conditions during which they are displayed to conspecifics.
Collapse
Affiliation(s)
- Alexander E. Hausmann
- Division of Evolutionary Biology, Ludwig-Maximilians-Universität München, Grosshaderner Strasse 2, 82152 Planegg-Martinsried, Germany
| | - Chi-Yun Kuo
- Division of Evolutionary Biology, Ludwig-Maximilians-Universität München, Grosshaderner Strasse 2, 82152 Planegg-Martinsried, Germany
- Smithsonian Tropical Research Institute, Gamboa 0843-03092, Panama
| | - Marília Freire
- Division of Evolutionary Biology, Ludwig-Maximilians-Universität München, Grosshaderner Strasse 2, 82152 Planegg-Martinsried, Germany
| | - Nicol Rueda-M
- Department of Biology, Faculty of Natural Sciences, Universidad del Rosario, Carrera 24 No 63C-69, Bogotá 111221, Colombia
| | - Mauricio Linares
- Department of Biology, Faculty of Natural Sciences, Universidad del Rosario, Carrera 24 No 63C-69, Bogotá 111221, Colombia
| | - Carolina Pardo-Diaz
- Department of Biology, Faculty of Natural Sciences, Universidad del Rosario, Carrera 24 No 63C-69, Bogotá 111221, Colombia
| | - Camilo Salazar
- Department of Biology, Faculty of Natural Sciences, Universidad del Rosario, Carrera 24 No 63C-69, Bogotá 111221, Colombia
| | - Richard M. Merrill
- Division of Evolutionary Biology, Ludwig-Maximilians-Universität München, Grosshaderner Strasse 2, 82152 Planegg-Martinsried, Germany
| |
Collapse
|
18
|
Xu M, Shaw KL. Extensive Linkage and Genetic Coupling of Song and Preference Loci Underlying Rapid Speciation in Laupala Crickets. J Hered 2021; 112:204-213. [PMID: 33438016 DOI: 10.1093/jhered/esab001] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Accepted: 01/11/2021] [Indexed: 12/20/2022] Open
Abstract
In nature, closely related species commonly display divergent mating behaviors, suggesting a central role for such traits in the origin of species. Elucidating the genetic basis of divergence in these traits is necessary to understand the evolutionary process leading to reproductive barriers and speciation. The rapidly speciating Hawaiian crickets of the genus Laupala provides an ideal system for dissecting the genetic basis of mating behavior divergence. In Laupala, closely related species differ markedly in male song pulse rate and female preference for pulse rate. These behaviors play an important role in determining mating patterns. Previous studies identified a genetic architecture consisting of numerous small to moderate effect loci causing interspecific differences in pulse rate and preference, including colocalizing pulse rate and preference QTL on linkage group one (LG1). To further interrogate these QTL, we conduct a fine mapping study using high-density SNP linkage maps. With improved statistical power and map resolution, we provide robust evidence for genetic coupling between song and preference, along with two additional pulse rate QTL on LG1, revealing a more resolved picture of the genetic architecture underlying mating behavior divergence. Our sequence-based genetic map, along with dramatically narrowed QTL confidence intervals, allowed us to annotate genes within the QTL regions and identify several exciting candidate genes underlying variation in pulse rate and preference divergence. Such knowledge suggests potential molecular mechanisms underlying the evolution of behavioral barriers.
Collapse
Affiliation(s)
- Mingzi Xu
- Department of Neurobiology and Behavior, Cornell University, Ithaca, NY
| | - Kerry L Shaw
- Department of Neurobiology and Behavior, Cornell University, Ithaca, NY
| |
Collapse
|
19
|
Dean LL, Dunstan HR, Reddish A, MacColl ADC. Courtship behavior, nesting microhabitat, and assortative mating in sympatric stickleback species pairs. Ecol Evol 2021; 11:1741-1755. [PMID: 33614001 PMCID: PMC7882950 DOI: 10.1002/ece3.7164] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2020] [Revised: 11/26/2020] [Accepted: 12/14/2020] [Indexed: 12/28/2022] Open
Abstract
The maintenance of reproductive isolation in the face of gene flow is a particularly contentious topic, but differences in reproductive behavior may provide the key to explaining this phenomenon. However, we do not yet fully understand how behavior contributes to maintaining species boundaries. How important are behavioral differences during reproduction? To what extent does assortative mating maintain reproductive isolation in recently diverged populations and how important are "magic traits"? Assortative mating can arise as a by-product of accumulated differences between divergent populations as well as an adaptive response to contact between those populations, but this is often overlooked. Here we address these questions using recently described species pairs of three-spined stickleback (Gasterosteus aculeatus), from two separate locations and a phenotypically intermediate allopatric population on the island of North Uist, Scottish Western Isles. We identified stark differences in the preferred nesting substrate and courtship behavior of species pair males. We showed that all males selectively court females of their own ecotype and all females prefer males of the same ecotype, regardless of whether they are from species pairs or allopatric populations. We also showed that mate choice does not appear to be driven by body size differences (a potential "magic trait"). By explicitly comparing the strength of these mating preferences between species pairs and single-ecotype locations, we were able to show that present levels of assortative mating due to direct mate choice are likely a by-product of other adaptations between ecotypes, and not subject to obvious selection in species pairs. Our results suggest that ecological divergence in mating characteristics, particularly nesting microhabitat may be more important than direct mate choice in maintaining reproductive isolation in stickleback species pairs.
Collapse
Affiliation(s)
- Laura L. Dean
- School of Life SciencesUniversity of NottinghamNottinghamUK
| | | | - Amelia Reddish
- School of Life SciencesUniversity of NottinghamNottinghamUK
| | | |
Collapse
|
20
|
Byers KJRP, Darragh K, Fernanda Garza S, Abondano Almeida D, Warren IA, Rastas PMA, Merrill RM, Schulz S, McMillan WO, Jiggins CD. Clustering of loci controlling species differences in male chemical bouquets of sympatric Heliconius butterflies. Ecol Evol 2021; 11:89-107. [PMID: 33437416 PMCID: PMC7790645 DOI: 10.1002/ece3.6947] [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: 07/23/2020] [Revised: 09/29/2020] [Accepted: 09/30/2020] [Indexed: 12/23/2022] Open
Abstract
The degree to which loci promoting reproductive isolation cluster in the genome-that is, the genetic architecture of reproductive isolation-can influence the tempo and mode of speciation. Tight linkage between these loci can facilitate speciation in the face of gene flow. Pheromones play a role in reproductive isolation in many Lepidoptera species, and the role of endogenously produced compounds as secondary metabolites decreases the likelihood of pleiotropy associated with many barrier loci. Heliconius butterflies use male sex pheromones to both court females (aphrodisiac wing pheromones) and ward off male courtship (male-transferred antiaphrodisiac genital pheromones), and it is likely that these compounds play a role in reproductive isolation between Heliconius species. Using a set of backcross hybrids between H. melpomene and H. cydno, we investigated the genetic architecture of putative male pheromone compound production. We found a set of 40 significant quantitative trait loci (QTL) representing 33 potential pheromone compounds. QTL clustered significantly on two chromosomes, chromosome 8 for genital compounds and chromosome 20 for wing compounds, and chromosome 20 was enriched for potential pheromone biosynthesis genes. There was minimal overlap between pheromone QTL and known QTL for mate choice and color pattern. Nonetheless, we did detect linkage between a QTL for wing androconial area and optix, a color pattern locus known to play a role in reproductive isolation in these species. This tight clustering of putative pheromone loci might contribute to coincident reproductive isolating barriers, facilitating speciation despite ongoing gene flow.
Collapse
Affiliation(s)
- Kelsey J. R. P. Byers
- Department of ZoologyUniversity of CambridgeCambridgeUK
- Smithsonian Tropical Research InstitutePanamaPanama
- Present address:
Department of Cell and Developmental BiologyJohn Innes CentreNorwichUK
| | - Kathy Darragh
- Department of ZoologyUniversity of CambridgeCambridgeUK
- Smithsonian Tropical Research InstitutePanamaPanama
- Present address:
Department of Evolution and EcologyUniversity of California DavisDavisCAUSA
| | - Sylvia Fernanda Garza
- Smithsonian Tropical Research InstitutePanamaPanama
- Present address:
Department of Collective BehaviourMax Planck Institute of Animal BehaviourKonstanzGermany
| | - Diana Abondano Almeida
- Smithsonian Tropical Research InstitutePanamaPanama
- Present address:
Institute for Ecology, Evolution and DiversityGoethe UniversitätFrankfurtGermany
| | - Ian A. Warren
- Department of ZoologyUniversity of CambridgeCambridgeUK
| | | | - Richard M. Merrill
- Smithsonian Tropical Research InstitutePanamaPanama
- Division of Evolutionary BiologyLudwig‐Maximilians‐Universität MünchenMunichGermany
| | - Stefan Schulz
- Institute of Organic ChemistryDepartment of Life SciencesTechnische Universität BraunschweigBraunschweigGermany
| | | | - Chris D. Jiggins
- Department of ZoologyUniversity of CambridgeCambridgeUK
- Smithsonian Tropical Research InstitutePanamaPanama
| |
Collapse
|
21
|
Kulikov AM, Sorokina SY, Melnikov AI, Gornostaev NG, Seleznev DG, Lazebny OE. The effects of the sex chromosomes on the inheritance of species-specific traits of the copulatory organ shape in Drosophila virilis and Drosophila lummei. PLoS One 2020; 15:e0244339. [PMID: 33373382 PMCID: PMC7771703 DOI: 10.1371/journal.pone.0244339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Accepted: 12/07/2020] [Indexed: 11/30/2022] Open
Abstract
The shape of the male genitalia in many taxa is the most rapidly evolving morphological structure, often driving reproductive isolation, and is therefore widely used in systematics as a key character to distinguish between sibling species. However, only a few studies have used the genital arch of the male copulatory organ as a model to study the genetic basis of species-specific differences in the Drosophila copulatory system. Moreover, almost nothing is known about the effects of the sex chromosomes on the shape of the male mating organ. In our study, we used a set of crosses between D. virilis and D. lummei and applied the methods of quantitative genetics to assess the variability of the shape of the male copulatory organ and the effects of the sex chromosomes and autosomes on its variance. Our results showed that the male genital shape depends on the species composition of the sex chromosomes and autosomes. Epistatic interactions of the sex chromosomes with autosomes and the species origin of the Y-chromosome in a male in interspecific crosses also influenced the expression of species-specific traits in the shape of the male copulatory system. Overall, the effects of sex chromosomes were comparable to the effects of autosomes despite the great differences in gene numbers between them. It may be reasonably considered that sexual selection for specific genes associated with the shape of the male mating organ prevents the demasculinization of the X chromosome.
Collapse
Affiliation(s)
- Alex M. Kulikov
- Department of Evolutionary Genetics of Development, Koltzov Institute of Developmental Biology of the Russian Academy of Sciences, Moscow, Russia
| | - Svetlana Yu. Sorokina
- Department of Evolutionary Genetics of Development, Koltzov Institute of Developmental Biology of the Russian Academy of Sciences, Moscow, Russia
| | - Anton I. Melnikov
- Department of Evolutionary Genetics of Development, Koltzov Institute of Developmental Biology of the Russian Academy of Sciences, Moscow, Russia
| | - Nick G. Gornostaev
- Department of Evolutionary Genetics of Development, Koltzov Institute of Developmental Biology of the Russian Academy of Sciences, Moscow, Russia
| | - Dmitriy G. Seleznev
- Department of Ecology of Aquatic Invertebrates, Papanin Institute for Biology of Inland Waters of the Russian Academy of Sciences, Borok village, Yaroslavl Region, Russia
| | - Oleg E. Lazebny
- Department of Evolutionary Genetics of Development, Koltzov Institute of Developmental Biology of the Russian Academy of Sciences, Moscow, Russia
- * E-mail:
| |
Collapse
|
22
|
Smolinský R, Baláž V, Nürnberger B. Tadpoles of hybridising fire-bellied toads (B. bombina and B. variegata) differ in their susceptibility to predation. PLoS One 2020; 15:e0231804. [PMID: 33285552 PMCID: PMC7721483 DOI: 10.1371/journal.pone.0231804] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 11/17/2020] [Indexed: 12/02/2022] Open
Abstract
The role of adaptive divergence in the formation of new species has been the subject of much recent debate. The most direct evidence comes from traits that can be shown to have diverged under natural selection and that now contribute to reproductive isolation. Here, we investigate differential adaptation of two fire-bellied toads (Anura, Bombinatoridae) to two types of aquatic habitat. Bombina bombina and B. variegata are two anciently diverged taxa that now reproduce in predator-rich ponds and ephemeral aquatic sites, respectively. Nevertheless, they hybridise extensively wherever their distribution ranges adjoin. We show in laboratory experiments that, as expected, B. variegata tadpoles are at relatively greater risk of predation from dragonfly larvae, even when they display a predator-induced phenotype. These tadpoles spent relatively more time swimming and so prompted more attacks from the visually hunting predators. We argue in the discussion that genomic regions linked to high activity in B. variegata should be barred from introgression into the B. bombina gene pool and thus contribute to gene flow barriers that keep the two taxa from merging into one.
Collapse
Affiliation(s)
- Radovan Smolinský
- Research Facility Studenec, Institute of Vertebrate Biology, Czech Academy of Sciences, Brno, Czech Republic
| | - Vojtech Baláž
- Faculty of Veterinary Hygiene and Ecology, University of Veterinary and Pharmaceutical Sciences, Brno, Czech Republic
| | - Beate Nürnberger
- Research Facility Studenec, Institute of Vertebrate Biology, Czech Academy of Sciences, Brno, Czech Republic
| |
Collapse
|
23
|
Kess T, Brachmann M, Boulding EG. Putative chromosomal rearrangements are associated primarily with ecotype divergence rather than geographic separation in an intertidal, poorly dispersing snail. J Evol Biol 2020; 34:193-207. [PMID: 33108001 DOI: 10.1111/jeb.13724] [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: 10/29/2019] [Revised: 09/29/2020] [Accepted: 10/14/2020] [Indexed: 12/12/2022]
Abstract
Littorina saxatilis is becoming a model system for understanding the genomic basis of ecological speciation. The parallel formation of crab-adapted ecotypes that exhibit partial reproductive isolation from wave-adapted ecotypes has enabled genomic investigation of conspicuous shell traits. Recent genomic studies suggest that chromosomal rearrangements may enable ecotype divergence by reducing gene flow. However, the genomic architecture of traits that are divergent between ecotypes remains poorly understood. Here, we use 11,504 single nucleotide polymorphism (SNP) markers called using the recently released L. saxatilis genome to genotype 462 crab ecotype, wave ecotype and phenotypically intermediate Spanish L. saxatilis individuals with scored phenotypes. We used redundancy analysis to study the genetic architecture of loci associated with shell shape, shape corrected for size, shell size and shell ornamentation, and to compare levels of co-association among different traits. We discovered 341 SNPs associated with shell traits. Loci associated with trait divergence between ecotypes were often located inside putative chromosomal rearrangements recently characterized in Swedish L. saxatilis. In contrast, we found that shell shape corrected for size varied primarily by geographic site rather than by ecotype and showed little association with these putative rearrangements. We conclude that genomic regions of elevated divergence inside putative rearrangements were associated with divergence of L. saxatilis ecotypes along steep environmental axes-consistent with models of adaptation with gene flow-but were not associated with divergence among the three geographical sites. Our findings support predictions from models indicating the importance of genomic regions of reduced recombination allowing co-association of loci during ecological speciation with ongoing gene flow.
Collapse
Affiliation(s)
- Tony Kess
- Department of Integrative Biology, University of Guelph, Guelph, ON, Canada
| | - Matthew Brachmann
- Department of Integrative Biology, University of Guelph, Guelph, ON, Canada
| | | |
Collapse
|
24
|
Berdan EL, Fuller RC, Kozak GM. Genomic landscape of reproductive isolation in Lucania killifish: The role of sex loci and salinity. J Evol Biol 2020; 34:157-174. [PMID: 33118222 PMCID: PMC7894299 DOI: 10.1111/jeb.13725] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2019] [Revised: 10/01/2020] [Accepted: 10/14/2020] [Indexed: 01/24/2023]
Abstract
Adaptation to different environments can directly and indirectly generate reproductive isolation between species. Bluefin killifish (Lucania goodei) and rainwater killifish (L. parva) are sister species that have diverged across a salinity gradient and are reproductively isolated by habitat, behavioural, extrinsic and intrinsic post-zygotic isolation. We asked if salinity adaptation contributes indirectly to other forms of reproductive isolation via linked selection and hypothesized that low recombination regions, such as sex chromosomes or chromosomal rearrangements, might facilitate this process. We conducted QTL mapping in backcrosses between L. parva and L. goodei to explore the genetic architecture of salinity tolerance, behavioural isolation and intrinsic isolation. We mapped traits relative to a chromosome that has undergone a centric fusion in L. parva (relative to L. goodei). We found that the sex locus appears to be male determining (XX-XY), was located on the fused chromosome and was implicated in intrinsic isolation. QTL associated with salinity tolerance were spread across the genome and did not overly co-localize with regions associated with behavioural or intrinsic isolation. This preliminary analysis of the genetic architecture of reproductive isolation between Lucania species does not support the hypothesis that divergent natural selection for salinity tolerance led to behavioural and intrinsic isolation as a by-product. Combined with previous studies in this system, our work suggests that adaptation as a function of salinity contributes to habitat isolation and that reinforcement may have contributed to the evolution of behavioural isolation instead, possibly facilitated by linkage between behavioural isolation and intrinsic isolation loci on the fused chromosome.
Collapse
Affiliation(s)
- Emma L Berdan
- Department of Marine Sciences, University of Gothenburg, Gothenburg, Sweden
| | - Rebecca C Fuller
- Department of Animal Biology, University of Illinois Urbana-Champaign, Champaign, IL, USA
| | - Genevieve M Kozak
- Department of Biology, University of Massachusetts-Dartmouth, Dartmouth, MA, USA
| |
Collapse
|
25
|
Rossi M, Hausmann AE, Thurman TJ, Montgomery SH, Papa R, Jiggins CD, McMillan WO, Merrill RM. Visual mate preference evolution during butterfly speciation is linked to neural processing genes. Nat Commun 2020; 11:4763. [PMID: 32958765 PMCID: PMC7506007 DOI: 10.1038/s41467-020-18609-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Accepted: 08/26/2020] [Indexed: 02/06/2023] Open
Abstract
Many animal species remain separate not because their individuals fail to produce viable hybrids but because they "choose" not to mate. However, we still know very little of the genetic mechanisms underlying changes in these mate preference behaviours. Heliconius butterflies display bright warning patterns, which they also use to recognize conspecifics. Here, we couple QTL for divergence in visual preference behaviours with population genomic and gene expression analyses of neural tissue (central brain, optic lobes and ommatidia) across development in two sympatric Heliconius species. Within a region containing 200 genes, we identify five genes that are strongly associated with divergent visual preferences. Three of these have previously been implicated in key components of neural signalling (specifically an ionotropic glutamate receptor and two regucalcins), and overall our candidates suggest shifts in behaviour involve changes in visual integration or processing. This would allow preference evolution without altering perception of the wider environment.
Collapse
Affiliation(s)
- Matteo Rossi
- Division of Evolutionary Biology, LMU, Munich, Germany.
- Smithsonian Tropical Research Institute, Panama City, Panama.
| | | | - Timothy J Thurman
- Smithsonian Tropical Research Institute, Panama City, Panama
- Division of Biological Sciences, University of Montana, Montana, USA
| | | | - Riccardo Papa
- Smithsonian Tropical Research Institute, Panama City, Panama
- Department of Biology, University of Puerto Rico, San Juan, Puerto Rico
- Molecular Sciences and Research Center, University of Puerto Rico, San Juan, Puerto Rico
| | - Chris D Jiggins
- Smithsonian Tropical Research Institute, Panama City, Panama
- Department of Zoology, University of Cambridge, Cambridge, UK
| | - W Owen McMillan
- Smithsonian Tropical Research Institute, Panama City, Panama
| | - Richard M Merrill
- Division of Evolutionary Biology, LMU, Munich, Germany.
- Smithsonian Tropical Research Institute, Panama City, Panama.
| |
Collapse
|
26
|
Wang X, He Z, Shi S, Wu CI. Genes and speciation: is it time to abandon the biological species concept? Natl Sci Rev 2020; 7:1387-1397. [PMID: 34692166 PMCID: PMC8288927 DOI: 10.1093/nsr/nwz220] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Revised: 12/17/2019] [Accepted: 12/31/2019] [Indexed: 01/04/2023] Open
Abstract
The biological species concept (BSC) is the cornerstone of neo-Darwinian thinking. In BSC, species do not exchange genes either during or after speciation. However, as gene flow during speciation is increasingly being reported in a substantial literature, it seems time to reassess the revered, but often doubted, BSC. Contrary to the common perception, BSC should expect substantial gene flow at the onset of speciation, not least because geographical isolation develops gradually. Although BSC does not stipulate how speciation begins, it does require a sustained period of isolation for speciation to complete its course. Evidence against BSC must demonstrate that the observed gene flow does not merely occur at the onset of speciation but continues until its completion. Importantly, recent genomic analyses cannot reject this more realistic version of BSC, although future analyses may still prove it wrong. The ultimate acceptance or rejection of BSC is not merely about a historical debate; rather, it is about the fundamental nature of species - are species (and, hence, divergent adaptations) driven by a relatively small number of genes, or by thousands of them? Many levels of biology, ranging from taxonomy to biodiversity, depend on this resolution.
Collapse
Affiliation(s)
- Xinfeng Wang
- State Key Laboratory of Biocontrol, Guangdong Key Lab of Plant Resources, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Ziwen He
- State Key Laboratory of Biocontrol, Guangdong Key Lab of Plant Resources, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Suhua Shi
- State Key Laboratory of Biocontrol, Guangdong Key Lab of Plant Resources, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Chung-I Wu
- State Key Laboratory of Biocontrol, Guangdong Key Lab of Plant Resources, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
- Department of Ecology and Evolution, University of Chicago, Illinois 60637, USA
| |
Collapse
|
27
|
Veller C, Muralidhar P, Haig D. On the logic of Fisherian sexual selection. Evolution 2020; 74:1234-1245. [PMID: 32128812 DOI: 10.1111/evo.13944] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Revised: 01/22/2020] [Accepted: 02/11/2020] [Indexed: 12/29/2022]
Abstract
In Fisher's model of sexual selection, a female preference for a male trait spreads together with the trait because their genetic bases become correlated. This can be interpreted as a "greenbeard" system: a preference gene, by inducing a female to mate with a trait-bearing male, favors itself because the male is disproportionately likely also to carry the preference gene. Here, we use this logic to argue that Fisherian sexual selection in diploids proceeds via two channels: (i) trait-bearing males are disproportionately the product of matings between preference-bearing mothers and trait-bearing fathers, and thus trait and preference genes are correlated "in trans"; (ii) trait and preference genes come into gametic phase disequilibrium, and thus are correlated "in cis." Gametic phase disequilibrium is generated by three distinct mechanisms that we identify. The trans channel does not operate when sexual selection is restricted to the haploid phase, and therefore represents a fundamental difference between haploid and diploid models of sexual selection. We show that the cis and trans channels contribute equally to the spread of the preference when recombination between the preference and trait loci is free, but that the trans channel is substantially more important when linkage is tight.
Collapse
Affiliation(s)
- Carl Veller
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, 02138.,Program for Evolutionary Dynamics, Harvard University, Cambridge, MA, 02138
| | - Pavitra Muralidhar
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, 02138.,Program for Evolutionary Dynamics, Harvard University, Cambridge, MA, 02138
| | - David Haig
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, 02138
| |
Collapse
|
28
|
González-Rojas MF, Darragh K, Robles J, Linares M, Schulz S, McMillan WO, Jiggins CD, Pardo-Diaz C, Salazar C. Chemical signals act as the main reproductive barrier between sister and mimetic Heliconius butterflies. Proc Biol Sci 2020; 287:20200587. [PMID: 32370676 PMCID: PMC7282924 DOI: 10.1098/rspb.2020.0587] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Colour pattern is the main trait that drives mate recognition between Heliconius species that are phylogenetically close. However, when this cue is compromised such as in cases of mimetic, sympatric and closely related species, alternative mating signals must evolve to ensure reproductive isolation and species integrity. The closely related species Heliconius melpomene malleti and H. timareta florencia occur in the same geographical region, and despite being co-mimics, they display strong reproductive isolation. In order to test which cues differ between species, and potentially contribute to reproductive isolation, we quantified differences in the wing phenotype and the male chemical profile. As expected, the wing colour pattern was indistinguishable between the two species, while the chemical profile of the androconial and genital males' extracts showed marked differences. We then conducted behavioural experiments to study the importance of these signals in mate recognition by females. In agreement with our previous results, we found that chemical blends and not wing colour pattern drive the preference of females for conspecific males. Also, experiments with hybrid males and females suggested an important genetic component for both chemical production and preference. Altogether, these results suggest that chemicals are the major reproductive barrier opposing gene flow between these two sister and co-mimic species.
Collapse
Affiliation(s)
- M F González-Rojas
- Department of Biology, Faculty of Natural Sciences and Mathematics, Universidad del Rosario, Bogota 111221, Colombia
| | - K Darragh
- Department of Zoology, University of Cambridge, Cambridge, Cambridgeshire CB2 3EJ, UK
| | - J Robles
- Department of Chemistry, Pontificia Universidad Javeriana, Bogota, Colombia
| | - M Linares
- Department of Biology, Faculty of Natural Sciences and Mathematics, Universidad del Rosario, Bogota 111221, Colombia
| | - S Schulz
- Institute of Organic Chemistry, Technische Universität Braunschweig, Braunschweig, Germany
| | | | - C D Jiggins
- Department of Zoology, University of Cambridge, Cambridge, Cambridgeshire CB2 3EJ, UK
| | - C Pardo-Diaz
- Department of Biology, Faculty of Natural Sciences and Mathematics, Universidad del Rosario, Bogota 111221, Colombia
| | - C Salazar
- Department of Biology, Faculty of Natural Sciences and Mathematics, Universidad del Rosario, Bogota 111221, Colombia
| |
Collapse
|
29
|
Fuxjäger L, Wanzenböck S, Ringler E, Wegner KM, Ahnelt H, Shama LNS. Within-generation and transgenerational plasticity of mate choice in oceanic stickleback under climate change. Philos Trans R Soc Lond B Biol Sci 2020; 374:20180183. [PMID: 30966960 DOI: 10.1098/rstb.2018.0183] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Plasticity, both within and across generations, can shape sexual traits involved in mate choice and reproductive success, and thus direct measures of fitness. Especially, transgenerational plasticity (TGP), where parental environment influences offspring plasticity in future environments, could compensate for otherwise negative effects of environmental change on offspring sexual traits. We conducted a mate choice experiment using stickleback ( Gasterosteus aculeatus) with different thermal histories (ambient 17°C or elevated 21°C) within and across generations under simulated ocean warming using outdoor mesocosms. Parentage analysis of egg clutches revealed that maternal developmental temperature and reproductive (mesocosm) environment affected egg size, with females that developed at 17°C laying smaller eggs in 21°C mesocosms, likely owing to metabolic costs at elevated temperature. Paternal developmental temperature interacted with the reproductive environment to influence mating success, particularly under simulated ocean warming, with males that developed at 21°C showing lower overall mating success compared with 17°C males, but higher mating success in 21°C mesocosms. Furthermore, mating success of males was influenced by the interaction between F1 developmental temperature and F0 parent acclimation temperature, demonstrating the potential role of both TGP and within-generation plasticity in shaping traits involved in sexual selection and mate choice, potentially facilitating rapid responses to environmental change. This article is part of the theme issue 'The role of plasticity in phenotypic adaptation to rapid environmental change'.
Collapse
Affiliation(s)
- Lukas Fuxjäger
- 1 Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung , Coastal Ecology Section, Wadden Sea Station Sylt, Hafenstrasse 43, 25992 List , Germany.,2 Department of Theoretical Biology, University of Vienna , Althanstrasse 14, Vienna , Austria
| | - Sylvia Wanzenböck
- 1 Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung , Coastal Ecology Section, Wadden Sea Station Sylt, Hafenstrasse 43, 25992 List , Germany.,2 Department of Theoretical Biology, University of Vienna , Althanstrasse 14, Vienna , Austria
| | - Eva Ringler
- 3 Messerli Research Institute, University of Veterinary Medicine Vienna, Medical University of Vienna, University of Vienna , Veterinaerplatz 1, 1210 Vienna , Austria
| | - K Mathias Wegner
- 1 Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung , Coastal Ecology Section, Wadden Sea Station Sylt, Hafenstrasse 43, 25992 List , Germany
| | - Harald Ahnelt
- 2 Department of Theoretical Biology, University of Vienna , Althanstrasse 14, Vienna , Austria.,4 First Zoological Department, Natural History Museum in Vienna , Burgring 7, 1010 Vienna , Austria
| | - Lisa N S Shama
- 1 Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung , Coastal Ecology Section, Wadden Sea Station Sylt, Hafenstrasse 43, 25992 List , Germany
| |
Collapse
|
30
|
Raffini F, Schneider RF, Franchini P, Kautt AF, Meyer A. Diving into divergence: Differentiation in swimming performances, physiology and gene expression between locally‐adapted sympatric cichlid fishes. Mol Ecol 2019; 29:1219-1234. [DOI: 10.1111/mec.15304] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2019] [Revised: 10/24/2019] [Accepted: 11/08/2019] [Indexed: 12/25/2022]
Affiliation(s)
- Francesca Raffini
- Lehrstuhl für Zoologie und Evolutionsbiologie Department of Biology University of Konstanz Konstanz Germany
- International Max Planck Research School (IMPRS) for Organismal Biology Max‐Planck‐Institut für Ornithologie Radolfzell Germany
- Max Planck Institute for Ornithology Radolfzell Germany
| | - Ralf F. Schneider
- Lehrstuhl für Zoologie und Evolutionsbiologie Department of Biology University of Konstanz Konstanz Germany
- International Max Planck Research School (IMPRS) for Organismal Biology Max‐Planck‐Institut für Ornithologie Radolfzell Germany
| | - Paolo Franchini
- Lehrstuhl für Zoologie und Evolutionsbiologie Department of Biology University of Konstanz Konstanz Germany
| | - Andreas F. Kautt
- Lehrstuhl für Zoologie und Evolutionsbiologie Department of Biology University of Konstanz Konstanz Germany
| | - Axel Meyer
- Lehrstuhl für Zoologie und Evolutionsbiologie Department of Biology University of Konstanz Konstanz Germany
- International Max Planck Research School (IMPRS) for Organismal Biology Max‐Planck‐Institut für Ornithologie Radolfzell Germany
| |
Collapse
|
31
|
Xu M, Shaw KL. Genetic coupling of signal and preference facilitates sexual isolation during rapid speciation. Proc Biol Sci 2019; 286:20191607. [PMID: 31640515 DOI: 10.1098/rspb.2019.1607] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The divergence of sexual signals is ultimately a coevolutionary process: while signals and preferences diverge between lineages, they must remain coordinated within lineages for matings to occur. Divergence in sexual signals makes a major contribution to evolving species barriers. Therefore, the genetic architecture underlying signal-preference coevolution is essential to understanding speciation but remains largely unknown. In Laupala crickets where male song pulse rate and female pulse rate preferences have coevolved repeatedly and rapidly, we tested two contrasting hypotheses for the genetic architecture underlying signal-preference coevolution: linkage disequilibrium between unlinked loci and genetic coupling (linkage disequilibrium resulting from pleiotropy of a shared locus or tight physical linkage). Through selective introgression and quantitative trait locus (QTL) fine mapping, we estimated the location of QTL underlying interspecific variation in both female preference and male pulse rate from the same mapping populations. Remarkably, map estimates of the pulse rate and preference loci are as close as 0.06 cM apart, the strongest evidence to date for genetic coupling between signal and preference loci. As the second pair of colocalizing signal and preference loci in the Laupala genome, our finding supports an intriguing pattern, pointing to a major role for genetic coupling in the quantitative evolution of a reproductive barrier and rapid speciation in Laupala. Owing to its effect on suppressing recombination, a coupled, quantitative genetic architecture offers a powerful and parsimonious genetic mechanism for signal-preference coevolution and the establishment of positive genetic covariance on which the Fisherian runaway process of sexual selection relies.
Collapse
Affiliation(s)
- Mingzi Xu
- Department of Neurobiology and Behavior, Cornell University, 215 Tower Rd, Ithaca, NY 14853, USA
| | - Kerry L Shaw
- Department of Neurobiology and Behavior, Cornell University, 215 Tower Rd, Ithaca, NY 14853, USA
| |
Collapse
|
32
|
Major Histocompatibility Complex (MHC) Genes and Disease Resistance in Fish. Cells 2019; 8:cells8040378. [PMID: 31027287 PMCID: PMC6523485 DOI: 10.3390/cells8040378] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Revised: 04/12/2019] [Accepted: 04/23/2019] [Indexed: 12/20/2022] Open
Abstract
Fascinating about classical major histocompatibility complex (MHC) molecules is their polymorphism. The present study is a review and discussion of the fish MHC situation. The basic pattern of MHC variation in fish is similar to mammals, with MHC class I versus class II, and polymorphic classical versus nonpolymorphic nonclassical. However, in many or all teleost fishes, important differences with mammalian or human MHC were observed: (1) The allelic/haplotype diversification levels of classical MHC class I tend to be much higher than in mammals and involve structural positions within but also outside the peptide binding groove; (2) Teleost fish classical MHC class I and class II loci are not linked. The present article summarizes previous studies that performed quantitative trait loci (QTL) analysis for mapping differences in teleost fish disease resistance, and discusses them from MHC point of view. Overall, those QTL studies suggest the possible importance of genomic regions including classical MHC class II and nonclassical MHC class I genes, whereas similar observations were not made for the genomic regions with the highly diversified classical MHC class I alleles. It must be concluded that despite decades of knowing MHC polymorphism in jawed vertebrate species including fish, firm conclusions (as opposed to appealing hypotheses) on the reasons for MHC polymorphism cannot be made, and that the types of polymorphism observed in fish may not be explained by disease-resistance models alone.
Collapse
|
33
|
Inter-chromosomal coupling between vision and pigmentation genes during genomic divergence. Nat Ecol Evol 2019; 3:657-667. [PMID: 30833758 DOI: 10.1038/s41559-019-0814-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Accepted: 01/11/2019] [Indexed: 12/30/2022]
Abstract
Recombination between loci underlying mate choice and ecological traits is a major evolutionary force acting against speciation with gene flow. The evolution of linkage disequilibrium between such loci is therefore a fundamental step in the origin of species. Here, we show that this process can take place in the absence of physical linkage in hamlets-a group of closely related reef fishes from the wider Caribbean that differ essentially in colour pattern and are reproductively isolated through strong visually-based assortative mating. Using full-genome analysis, we identify four narrow genomic intervals that are consistently differentiated among sympatric species in a backdrop of extremely low genomic divergence. These four intervals include genes involved in pigmentation (sox10), axial patterning (hoxc13a), photoreceptor development (casz1) and visual sensitivity (SWS and LWS opsins) that develop islands of long-distance and inter-chromosomal linkage disequilibrium as species diverge. The relatively simple genomic architecture of species differences facilitates the evolution of linkage disequilibrium in the presence of gene flow.
Collapse
|
34
|
Merrill RM, Rastas P, Martin SH, Melo MC, Barker S, Davey J, McMillan WO, Jiggins CD. Genetic dissection of assortative mating behavior. PLoS Biol 2019; 17:e2005902. [PMID: 30730873 PMCID: PMC6366751 DOI: 10.1371/journal.pbio.2005902] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2018] [Accepted: 11/06/2018] [Indexed: 12/26/2022] Open
Abstract
The evolution of new species is made easier when traits under divergent ecological selection are also mating cues. Such ecological mating cues are now considered more common than previously thought, but we still know little about the genetic changes underlying their evolution or more generally about the genetic basis for assortative mating behaviors. Both tight physical linkage and the existence of large-effect preference loci will strengthen genetic associations between behavioral and ecological barriers, promoting the evolution of assortative mating. The warning patterns of Heliconius melpomene and H. cydno are under disruptive selection due to increased predation of nonmimetic hybrids and are used during mate recognition. We carried out a genome-wide quantitative trait locus (QTL) analysis of preference behaviors between these species and showed that divergent male preference has a simple genetic basis. We identify three QTLs that together explain a large proportion (approximately 60%) of the difference in preference behavior observed between the parental species. One of these QTLs is just 1.2 (0-4.8) centiMorgans (cM) from the major color pattern gene optix, and, individually, all three have a large effect on the preference phenotype. Genomic divergence between H. cydno and H. melpomene is high but broadly heterogenous, and admixture is reduced at the preference-optix color pattern locus but not the other preference QTLs. The simple genetic architecture we reveal will facilitate the evolution and maintenance of new species despite ongoing gene flow by coupling behavioral and ecological aspects of reproductive isolation.
Collapse
Affiliation(s)
- Richard M. Merrill
- Division of Evolutionary Biology, Ludwig-Maximilians-Universität, München, Germany
- Department of Zoology, University of Cambridge, Cambridge, United Kingdom
- Smithsonian Tropical Research Institute, Panama City, Panama
| | - Pasi Rastas
- Department of Zoology, University of Cambridge, Cambridge, United Kingdom
| | - Simon H. Martin
- Department of Zoology, University of Cambridge, Cambridge, United Kingdom
| | - Maria C. Melo
- Smithsonian Tropical Research Institute, Panama City, Panama
- IST Austria, Klosterburg, Austria
| | - Sarah Barker
- Department of Zoology, University of Cambridge, Cambridge, United Kingdom
| | - John Davey
- Department of Zoology, University of Cambridge, Cambridge, United Kingdom
- Department of Biology, University of York, York, United Kingdom
| | | | - Chris D. Jiggins
- Department of Zoology, University of Cambridge, Cambridge, United Kingdom
| |
Collapse
|
35
|
The Genetics of Mating Song Evolution Underlying Rapid Speciation: Linking Quantitative Variation to Candidate Genes for Behavioral Isolation. Genetics 2019; 211:1089-1104. [PMID: 30647070 DOI: 10.1534/genetics.118.301706] [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] [Received: 10/16/2018] [Accepted: 01/11/2019] [Indexed: 02/07/2023] Open
Abstract
Differences in mating behaviors evolve early during speciation, eventually contributing to reproductive barriers between species. Knowledge of the genetic and genomic basis of these behaviors is therefore integral to a causal understanding of speciation. Acoustic behaviors are often part of the mating ritual in animal species. The temporal rhythms of mating songs are notably species-specific in many vertebrates and arthropods and often underlie assortative mating. Despite discoveries of mutations that disrupt the temporal rhythm of these songs, we know surprisingly little about genes affecting naturally occurring variation in the temporal pattern of singing behavior. In the rapidly speciating Hawaiian cricket genus Laupala, the striking species variation in song rhythms constitutes a behavioral barrier to reproduction between species. Here, we mapped the largest-effect locus underlying interspecific variation in song rhythm between two Laupala species to a narrow genomic region, wherein we find no known candidate genes affecting song temporal rhythm in Drosophila Whole-genome sequencing, gene prediction, and functional annotation of this region reveal an exciting and promising candidate gene, the putative cyclic nucleotide-gated ion channel-like gene, for natural variation in mating behavior. Identification and molecular characterization of the candidate gene reveals a nonsynonymous mutation in a conserved binding domain, suggesting that ion channels are important targets of selection on rhythmic signaling during establishment of behavioral isolation and rapid speciation.
Collapse
|
36
|
Role of sexual imprinting in assortative mating and premating isolation in Darwin's finches. Proc Natl Acad Sci U S A 2018; 115:E10879-E10887. [PMID: 30348758 DOI: 10.1073/pnas.1813662115] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Global biodiversity is being degraded at an unprecedented rate, so it is important to preserve the potential for future speciation. Providing for the future requires understanding speciation as a contemporary ecological process. Phylogenetically young adaptive radiations are a good choice for detailed study because diversification is ongoing. A key question is how incipient species become reproductively isolated from each other. Barriers to gene exchange have been investigated experimentally in the laboratory and in the field, but little information exists from the quantitative study of mating patterns in nature. Although the degree to which genetic variation underlying mate-preference learning is unknown, we provide evidence that two species of Darwin's finches imprint on morphological cues of their parents and mate assortatively. Statistical evidence of presumed imprinting is stronger for sons than for daughters and is stronger for imprinting on fathers than on mothers. In combination, morphology and species-specific song learned from the father constitute a barrier to interbreeding. The barrier becomes stronger the more the species diverge morphologically and ecologically. It occasionally breaks down, and the species hybridize. Hybridization is most likely to happen when species are similar to each other in adaptive morphological traits, e.g., body size and beak size and shape. Hybridization can lead to the formation of a new species reproductively isolated from the parental species as a result of sexual imprinting. Conservation of sufficiently diverse natural habitat is needed to sustain a large sample of extant biota and preserve the potential for future speciation.
Collapse
|
37
|
Ravinet M. Notes from a snail island: Littorinid evolution and adaptation. Mol Ecol 2018; 27:2781-2789. [PMID: 29802775 DOI: 10.1111/mec.14730] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Revised: 05/01/2018] [Accepted: 05/06/2018] [Indexed: 12/20/2022]
Abstract
The most successful study systems are built on a foundation of decades of research on the basic biology, ecology and life history of the organisms in question. Combined with new technologies, this can provide a formidable means to address important issues in evolutionary biology and molecular ecology. Littorinid marine snails are a good example of this, with a rich literature on their taxonomy, speciation, thermal tolerance and behavioural adaptations. In August 2017, an international meeting on Littorinid evolution was held at the Tjärnö Marine Research Laboratory in Western Sweden. In this meeting review, I provide a summary of some of the exciting work on parallel evolution, sexual selection and adaptation to environmental stress presented there. I argue that newly available genomic resources present an opportunity for integrating the traditionally divergent fields of speciation and environmental adaptation in Littorinid research.
Collapse
Affiliation(s)
- Mark Ravinet
- Centre for Ecological and Evolutionary Synthesis, University of Oslo, Oslo, Norway
| |
Collapse
|
38
|
Zimmer C, Riesch R, Jourdan J, Bierbach D, Arias-Rodriguez L, Plath M. Female Choice Undermines the Emergence of Strong Sexual Isolation between Locally Adapted Populations of Atlantic Mollies ( Poecilia mexicana). Genes (Basel) 2018; 9:E232. [PMID: 29724050 PMCID: PMC5977172 DOI: 10.3390/genes9050232] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Revised: 04/23/2018] [Accepted: 04/25/2018] [Indexed: 11/16/2022] Open
Abstract
Divergent selection between ecologically dissimilar habitats promotes local adaptation, which can lead to reproductive isolation (RI). Populations in the Poecilia mexicana species complex have independently adapted to toxic hydrogen sulfide and show varying degrees of RI. Here, we examined the variation in the mate choice component of prezygotic RI. Mate choice tests across drainages (with stimulus males from another drainage) suggest that specific features of the males coupled with a general female preference for yellow color patterns explain the observed variation. Analyses of male body coloration identified the intensity of yellow fin coloration as a strong candidate to explain this pattern, and common-garden rearing suggested heritable population differences. Male sexual ornamentation apparently evolved differently across sulfide-adapted populations, for example because of differences in natural counterselection via predation. The ubiquitous preference for yellow color ornaments in poeciliid females likely undermines the emergence of strong RI, as female discrimination in favor of own males becomes weaker when yellow fin coloration in the respective sulfide ecotype increases. Our study illustrates the complexity of the (partly non-parallel) pathways to divergence among replicated ecological gradients. We suggest that future work should identify the genomic loci involved in the pattern reported here, making use of the increasing genomic and transcriptomic datasets available for our study system.
Collapse
Affiliation(s)
- Claudia Zimmer
- College of Animal Science & Technology, Northwest A&F University, Yangling 712100, China.
- Department of Ecology and Evolution, Goethe University of Frankfurt, Max-von-Laue-Straße 13, D-60438 Frankfurt am Main, Germany.
| | - Rüdiger Riesch
- Centre for Ecology, Evolution and Behaviour, School of Biological Sciences, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK.
| | - Jonas Jourdan
- Department of River Ecology and Conservation, Senckenberg Research Institute and Natural History Museum Frankfurt, D-63571 Gelnhausen, Germany.
| | - David Bierbach
- Department of Biology and Ecology of Fishes, Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Müggelseedamm 310, D-12587 Berlin, Germany.
| | - Lenin Arias-Rodriguez
- División Académica de Ciencias Biológicas, Universidad Juárez Autónoma de Tabasco (UJAT), 86150 Villahermosa, Tabasco, Mexico.
| | - Martin Plath
- College of Animal Science & Technology, Northwest A&F University, Yangling 712100, China.
- Shaanxi Key Laboratory of Molecular Biology for Agriculture, Northwest A&F University, Yangling 712100, China.
| |
Collapse
|