1
|
Lackey ACR, Murray AC, Mirza NA, Powell THQ. The role of sexual isolation during rapid ecological divergence: Evidence for a new dimension of isolation in Rhagoletis pomonella. J Evol Biol 2023. [PMID: 37173822 DOI: 10.1111/jeb.14179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Revised: 03/05/2023] [Accepted: 03/23/2023] [Indexed: 05/15/2023]
Abstract
The pace of divergence and likelihood of speciation often depends on how and when different types of reproductive barriers evolve. Questions remain about how reproductive isolation evolves after initial divergence. We tested for the presence of sexual isolation (reduced mating between populations due to divergent mating preferences and traits) in Rhagoletis pomonella flies, a model system for incipient ecological speciation. We measured the strength of sexual isolation between two very recently diverged (~170 generations) sympatric populations, adapted to different host fruits (hawthorn and apple). We found that flies from both populations were more likely to mate within than between populations. Thus, sexual isolation may play an important role in reducing gene flow allowed by early-acting ecological barriers. We also tested how warmer temperatures predicted under climate change could alter sexual isolation and found that sexual isolation was markedly asymmetric under warmer temperatures - apple males and hawthorn females mated randomly while apple females and hawthorn males mated more within populations than between. Our findings provide a window into the early speciation process and the role of sexual isolation after initial ecological divergence, in addition to examining how environmental conditions could shape the likelihood of further divergence.
Collapse
Affiliation(s)
- Alycia C R Lackey
- University of Louisville, Louisville, Kentucky, USA
- Binghamton University, Binghamton, New York, USA
| | | | | | | |
Collapse
|
2
|
BeVier GT, Ayton C, Brock KM. It ain’t easy being orange: lizard colour morphs occupying highly vegetated microhabitats suffer greater ectoparasitism. AMPHIBIA-REPTILIA 2022. [DOI: 10.1163/15685381-bja10097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Abstract
Intraspecific colour morphs usually differ in more traits than just colour. These traits can manifest as differences in morph physiology, behaviour, and ecology. Ecological differences among colour morphs, such as the degree of parasitism, can influence the evolution, maintenance, and loss of morphs from populations. High ectoparasite load can directly and deleteriously impact host fitness, and thus could influence colour morph persistence in populations if certain morphs are more frequently exposed to parasites or are more susceptible to parasitism. The Aegean wall lizard, Podarcis erhardii, is a colour polymorphic island lizard that is parasitized externally by ticks and mites. These ectoparasites can affect aspects of host lizard behaviour and physiology – including thermoregulation and body mass – and therefore are an important factor influencing the ecology and fitness of P. erhardii. We find that among sympatric colour morphs, ectoparasite loads differ; namely, monochromatic orange morphs have the highest numbers of ectoparasites, and in general, morphs with orange alleles (orange, orange-white, and orange-yellow) are more heavily parasitized by ticks and mites than the other morphs. Our results indicate that morphs with orange alleles tend to occupy microhabitats with significantly more vegetation cover and thus may increase their exposure to ticks and mites. Ecological differences between morphs could be an important factor contributing to demonstrated patterns of orange morph rarity and loss in P. erhardii populations.
Collapse
Affiliation(s)
| | - Cole Ayton
- Department of Life and Environmental Science, School of Natural Sciences, University of California, Merced, CA 95343, USA
| | - Kinsey M. Brock
- Department of Environmental Science, Policy, and Management, College of Natural Resources, University of California, Berkeley, CA 94720, USA
| |
Collapse
|
3
|
Tschol M, Reid JM, Bocedi G. Strong spatial population structure shapes the temporal coevolutionary dynamics of costly female preference and male display. Evolution 2021; 76:636-648. [PMID: 34964487 PMCID: PMC9302702 DOI: 10.1111/evo.14426] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 11/17/2021] [Accepted: 11/26/2021] [Indexed: 12/01/2022]
Abstract
Female mating preferences for exaggerated male display traits are commonplace. Yet, comprehensive understanding of the evolution and persistence of costly female preference through indirect (Fisherian) selection in finite populations requires some explanation for the persistence of additive genetic variance (Va) underlying sexual traits, given that directional preference is expected to deplete Va in display and hence halt preference evolution. However, the degree to which Va, and hence preference‐display coevolution, may be prolonged by spatially variable sexual selection arising solely from limited gene flow and genetic drift within spatially structured populations has not been examined. Our genetically and spatially explicit model shows that spatial population structure arising in an ecologically homogeneous environment can facilitate evolution and long‐term persistence of costly preference given small subpopulations and low dispersal probabilities. Here, genetic drift initially creates spatial variation in female preference, leading to persistence of Va in display through “migration‐bias” of genotypes maladapted to emerging local sexual selection, thus fueling coevolution of costly preference and display. However, costs of sexual selection increased the probability of subpopulation extinction, limiting persistence of high preference‐display genotypes. Understanding long‐term dynamics of sexual selection systems therefore requires joint consideration of coevolution of sexual traits and metapopulation dynamics.
Collapse
Affiliation(s)
- Maximilian Tschol
- School of Biological Sciences, University of Aberdeen, Zoology Building, Tillydrone Avenue, Aberdeen, AB24 2TZ, UK
| | - Jane M Reid
- School of Biological Sciences, University of Aberdeen, Zoology Building, Tillydrone Avenue, Aberdeen, AB24 2TZ, UK.,Centre for Biodiversity Dynamics, Institutt for Biologi, NTNU, Realfagbygget, Gløshaugen, Høgskoleringen 5, Trondheim, N-7491, Norway
| | - Greta Bocedi
- School of Biological Sciences, University of Aberdeen, Zoology Building, Tillydrone Avenue, Aberdeen, AB24 2TZ, UK
| |
Collapse
|
4
|
Brock KM, McTavish EJ, Edwards DL. Color Polymorphism is a Driver of Diversification in the Lizard Family Lacertidae. Syst Biol 2021; 71:24-39. [PMID: 34146110 PMCID: PMC8677543 DOI: 10.1093/sysbio/syab046] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 06/05/2021] [Accepted: 06/11/2021] [Indexed: 11/13/2022] Open
Abstract
Color polymorphism-two or more heritable color phenotypes maintained within a single breeding population-is an extreme type of intraspecific diversity widespread across the tree of life. Color polymorphism is hypothesized to be an engine for speciation, where morph loss or divergence between distinct color morphs within a species results in the rapid evolution of new lineages, and thus, color polymorphic lineages are expected to display elevated diversification rates. Multiple species in the lizard family Lacertidae are color polymorphic, making them an ideal group to investigate the evolutionary history of this trait and its influence on macroevolution. Here, we produce a comprehensive species-level phylogeny of the lizard family Lacertidae to reconstruct the evolutionary history of color polymorphism and test if color polymorphism has been a driver of diversification. Accounting for phylogenetic uncertainty with multiple phylogenies and simulation studies, we estimate an ancient origin of color polymorphism (111 Ma) within the Lacertini tribe (subfamily Lacertinae). Color polymorphism most likely evolved few times in the Lacertidae and has been lost at a much faster rate than gained. Evolutionary transitions to color polymorphism are associated with shifts in increased net diversification rate in this family of lizards. Taken together, our empirical results support long-standing theoretical expectations that color polymorphism is a driver of diversification.[Color polymorphism; Lacertidae; state-dependent speciation extinction models; trait-dependent diversification.].
Collapse
Affiliation(s)
- Kinsey M Brock
- Department of Life & Environmental Sciences, School of Natural Sciences, University of California, Merced 5400 N. Lake Rd., Merced, CA 95340 USA
- Quantitative & Systems Biology Graduate Group, School of Natural Sciences, University of California, Merced 5400 N. Lake Rd., Merced, CA 95340 USA
| | - Emily Jane McTavish
- Department of Life & Environmental Sciences, School of Natural Sciences, University of California, Merced 5400 N. Lake Rd., Merced, CA 95340 USA
| | - Danielle L Edwards
- Department of Life & Environmental Sciences, School of Natural Sciences, University of California, Merced 5400 N. Lake Rd., Merced, CA 95340 USA
| |
Collapse
|
5
|
Chelini MC, Brock K, Yeager J, Edwards DL. Environmental drivers of sexual dimorphism in a lizard with alternative mating strategies. J Evol Biol 2021; 34:1241-1255. [PMID: 34101919 DOI: 10.1111/jeb.13881] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 03/29/2021] [Accepted: 05/12/2021] [Indexed: 11/28/2022]
Abstract
Understanding the relative importance of sexual and natural selection in shaping morphological traits is a long-standing goal of evolutionary ecology. Male-biased sexual size dimorphism (SSD) is typically associated with male-male competition. Similarly, male polymorphisms are considered a consequence of competitive social interactions. This classic paradigm overlooks the fact that environmental factors mediate social interactions and can lead to ecological adaptations. Common side-blotched lizards, Uta stansburiana, are a model system for this paradigm due to well-known rock-paper-scissors social dynamics between male morphs. SSD in this species has been considered primarily a consequence of social interactions, with male size resulting from the number of morphs in each population and female size being constrained through fecundity benefits. We test if the environment explains intraspecific variation in SSD and number of male morphs in U. stansburiana. By compiling data from 49 populations, we show that environmental variables are stronger predictors of SSD than the number of male morphs. Similarly, we show that the environment mediates SSD and potentially contributes to morph loss in colder environments. We propose that the environment favours smaller males in areas of high seasonality. Our results demonstrate the importance of the environment as a mediator of SSD.
Collapse
Affiliation(s)
| | - Kinsey Brock
- School of Natural Sciences, University of California, Merced, Merced, CA, USA
| | - Justin Yeager
- School of Natural Sciences, University of California, Merced, Merced, CA, USA
| | - Danielle L Edwards
- School of Natural Sciences, University of California, Merced, Merced, CA, USA
| |
Collapse
|
6
|
Hodge JR, Santini F, Wainwright PC. Colour dimorphism in labrid fishes as an adaptation to life on coral reefs. Proc Biol Sci 2020; 287:20200167. [PMID: 32183627 PMCID: PMC7126040 DOI: 10.1098/rspb.2020.0167] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Accepted: 03/02/2020] [Indexed: 12/23/2022] Open
Abstract
Conspicuous coloration displayed by animals that express sexual colour dimorphism is generally explained as an adaptation to sexual selection, yet the interactions and relative effects of selective forces influencing colour dimorphism are largely unknown. Qualitatively, colour dimorphism appears more pronounced in marine fishes that live on coral reefs where traits associated with strong sexual selection are purportedly more common. Using phylogenetic comparative analysis, we show that wrasses and parrotfishes exclusive to coral reefs are the most colour dimorphic, but surprisingly, the effect of habitat is not influenced by traits associated with strong sexual selection. Rather, habitat-specific selective forces, including clear water and structural refuge, promote the evolution of pronounced colour dimorphism that manifests colours less likely to be displayed in other habitats. Our results demonstrate that environmental context ultimately determines the evolution of conspicuous coloration in colour-dimorphic labrid fishes, despite other influential selective forces.
Collapse
Affiliation(s)
- J R Hodge
- Department of Evolution and Ecology, University of California, Davis, CA 95616, USA
| | - F Santini
- Department of Evolution and Ecology, University of California, Davis, CA 95616, USA
| | - P C Wainwright
- Department of Evolution and Ecology, University of California, Davis, CA 95616, USA
| |
Collapse
|
7
|
Gripshover ND, Jayne BC. Visual Contrast and Intensity Affect Perch Choice of Brown Tree Snakes (Boiga irregularis) and Boa Constrictors (Boa constrictor). ZOOLOGY 2020; 139:125744. [PMID: 32070798 DOI: 10.1016/j.zool.2020.125744] [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: 10/16/2019] [Revised: 01/15/2020] [Accepted: 01/16/2020] [Indexed: 10/25/2022]
Abstract
Habitat structure can affect animal movement both by affecting the mechanical demands of locomotion and by influencing where animals choose to go. Arboreal habitats facilitate studying path choice by animals because variation in branch structure has known mechanical consequences, and different branches create discrete choices. Recent laboratory studies have found that arboreal snakes can use vision to select shapes and locations of destinations that mechanically facilitate bridging gaps. However, the extent to which the appearance of objects unrelated to biomechanical demands affects the choice of destinations remains poorly understood for most animal taxa including snakes. Hence, we manipulated the intensity (black, gray, or white), contrast, structure, and locations of destinations to test for their combined effects on perch choice during gap bridging of brown tree snakes and boa constrictors. For a white background and a given perch structure and location, both species had significant preferences for darker perches. The preference for darker destinations was strong enough to override or reduce some preferences for biomechanically advantageous destinations such as those having secondary branches or being located closer or along a straighter trajectory. These results provide a striking example of how visual cues unrelated to the physical structure of surfaces, such as contrast and intensity, can bias choice and, in some cases, supersede a preference for mechanically beneficial surfaces. Because these two species are so phylogenetically distant, some of their similar preferences suggest a sensory bias that may be widespread in snakes. The manipulation of surface color may facilitate management of invasive species, such as the brown tree snakes, by enhancing the efficiency of traps or making certain objects less attractive to them.
Collapse
Affiliation(s)
- Noah D Gripshover
- Department of Biological Sciences, PO Box 210006, University of Cincinnati, Cincinnati, OH, 45221-0006, USA.
| | - Bruce C Jayne
- Department of Biological Sciences, PO Box 210006, University of Cincinnati, Cincinnati, OH, 45221-0006, USA
| |
Collapse
|
8
|
Dong CM, McLean CA, Moussalli A, Stuart‐Fox D. Conserved visual sensitivities across divergent lizard lineages that differ in an ultraviolet sexual signal. Ecol Evol 2019; 9:11824-11832. [PMID: 31695890 PMCID: PMC6822044 DOI: 10.1002/ece3.5686] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Revised: 09/02/2019] [Accepted: 09/05/2019] [Indexed: 01/04/2023] Open
Abstract
The sensory drive hypothesis predicts the correlated evolution of signaling traits and sensory perception in differing environments. For visual signals, adaptive divergence in both color signals and visual sensitivities between populations may contribute to reproductive isolation and promote speciation, but this has rarely been tested or shown in terrestrial species. We tested whether opsin protein expression differs between divergent lineages of the tawny dragon (Ctenophorus decresii) that differ in the presence/absence of an ultraviolet sexual signal. We measured the expression of four retinal cone opsin genes (SWS1, SWS2, RH2, and LWS) using droplet digital PCR. We show that gene expression between lineages does not differ significantly, including the UV wavelength sensitive SWS1. We discuss these results in the context of mounting evidence that visual sensitivities are highly conserved in terrestrial systems. Multiple competing requirements may constrain divergence of visual sensitivities in response to sexual signals. Instead, signal contrast could be increased via alternative mechanisms, such as background selection. Our results contribute to a growing understanding of the roles of visual ecology, phylogeny, and behavior on visual system evolution in reptiles.
Collapse
Affiliation(s)
- Caroline M. Dong
- School of BioSciencesThe University of MelbourneParkvilleVictoriaAustralia
- Sciences DepartmentMuseums VictoriaCarltonVictoriaAustralia
| | - Claire A. McLean
- School of BioSciencesThe University of MelbourneParkvilleVictoriaAustralia
- Sciences DepartmentMuseums VictoriaCarltonVictoriaAustralia
| | | | - Devi Stuart‐Fox
- School of BioSciencesThe University of MelbourneParkvilleVictoriaAustralia
| |
Collapse
|
9
|
Resolving tradeoffs among crypsis, escape behavior, and microhabitat use in sexually dichromatic species. Oecologia 2018; 189:91-104. [PMID: 30430233 DOI: 10.1007/s00442-018-4301-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Accepted: 11/08/2018] [Indexed: 10/27/2022]
Abstract
Variation in color pattern between populations of cryptic animals is common and typically attributed to selection pressures from visual predators combined with variation in substrate composition. However, little is known about how cryptic color pattern relates to varied rates of predation, and few studies simultaneously analyze patterns of escape behavior and microhabitat use along with variation in color pattern, even though these traits evolve in tandem. Here, we use a combination of calibrated photographs and spectrometry to examine the influence of spatial heterogeneity in rates of predation on dorsal brightness in the Florida scrub lizard (Sceloporus woodi), a cryptic and sexually dimorphic species. Simultaneously, we analyze patterns of escape behavior and microhabitat use measured in the field. The results of this study indicate that populations inhabiting environments of increased predation have less color variation and more closely match the color of local substrate than populations sampled in environments of relaxed predation. Populations exposed to increased predation also show more pronounced escape behavior and are more selective in their use of microhabitat. Interestingly, geographic variation of dorsal brightness, escape behavior, and microhabitat use were greater for females than for males. Our results not only provide empirical evidence for theories of adaptive coloration, but suggest that sexual dichromatism can be maintained by selection pressures related to predation.
Collapse
|
10
|
Chang CH, Schult JE, Sanders J, Liu SH, Fuller RC. The vertical distributions and spawning site choices of red and yellow bluefin killifish Lucania goodei colour morphs. JOURNAL OF FISH BIOLOGY 2018; 93:396-400. [PMID: 30241110 DOI: 10.1111/jfb.13661] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Accepted: 05/27/2018] [Indexed: 06/08/2023]
Abstract
A genetic colour polymorphism is present in bluefin killifish Lucania goodei, where red and yellow anal-fin morphs coexist in clear springs, but the source of balancing selection is unknown. In a field study, vertical distributions did not differ between the morphs and there was little evidence that light environments differed qualitatively over the 200 cm at which fish were collected. A greenhouse study showed that both morphs preferred to spawn at shallow depths and hence vertical distribution and spawning site choice are unlikely to explain the maintenance of the colour polymorphism.
Collapse
Affiliation(s)
- Chia-Hao Chang
- Department of Animal Biology, School of Integrative Biology, University of Illinois, Champaign, Illinois
| | - Jessica E Schult
- College of Veterinary Medicine, University of Illinois, Champaign, Illinois
| | - Jonathan Sanders
- School of Integrative Biology, University of Illinois, Champaign, Illinois
| | - Shih-Hui Liu
- Biodiversity Research Center, Academia Sinica, Taipei City, Taiwan
| | - Rebecca C Fuller
- Department of Animal Biology, School of Integrative Biology, University of Illinois, Champaign, Illinois
| |
Collapse
|
11
|
Mitchem LD, Stanis S, Sutton NM, Turner Z, Fuller RC. The pervasive effects of lighting environments on sensory drive in bluefin killifish: an investigation into male/male competition, female choice, and predation. Curr Zool 2018; 64:499-512. [PMID: 30108631 PMCID: PMC6084612 DOI: 10.1093/cz/zoy038] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Accepted: 05/17/2018] [Indexed: 12/25/2022] Open
Abstract
Sensory drive predicts that the conditions under which signaling takes place have large effects on signals, sensory systems, and behavior. The coupling of an ecological genetics approach with sensory drive has been fruitful. An ecological genetics approach compares populations that experience different environments and asks whether population differences are adaptive and are the result of genetic and/or environmental variation. The multi-faceted effects of signaling environments are well-exemplified by the bluefin killifish. In this system, males with blue anal fins are abundant in tannin-stained swamps that lack UV/blue light but are absent in clear springs where UV/blue light is abundant. Past work indicates that lighting environments shape genetic and environmental variation in color patterns, visual systems, and behavior. Less is known about the selective forces creating the across population correlations between UV/blue light and the abundance of blue males. Here, we present three new experiments that investigate the roles of lighting environments on male competition, female mate choice, and predation. We found strong effects of lighting environments on male competition where blue males were more likely to emerge as dominant in tea-stained water than in clear water. Our preliminary study on predation indicated that blue males may be less susceptible to predation in tea-stained water than in clear water. However, there was little evidence for female preferences favoring blue males. The resulting pattern is one where the effects of lighting environments on genetic variation and phenotypic plasticity match the direction of selection and favor the expression of blue males in swamps.
Collapse
Affiliation(s)
- Lisa D Mitchem
- School of Integrative Biology, University of Illinois, Urbana, IL, USA
- Department of Biology, University of Virginia, Charlottesville, VA, USA
| | - Shannon Stanis
- School of Integrative Biology, University of Illinois, Urbana, IL, USA
| | - Nicholas M Sutton
- School of Integrative Biology, University of Illinois, Urbana, IL, USA
| | - Zachary Turner
- Department of Mathematics, University of Illinois, Urbana, IL, USA
| | - Rebecca C Fuller
- School of Integrative Biology, University of Illinois, Urbana, IL, USA
| | | |
Collapse
|
12
|
Paterson JE, Blouin-Demers G. Male throat colour polymorphism is related to differences in space use and in habitat selection in tree lizards. J Zool (1987) 2018. [DOI: 10.1111/jzo.12576] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- J. E. Paterson
- Department of Biology; University of Ottawa; Ottawa ON Canada
| | | |
Collapse
|
13
|
Ponkshe A, Endler JA. Effects of female preference intensity on the permissiveness of sexual trait polymorphisms. Ecol Evol 2018; 8:4518-4524. [PMID: 29760892 PMCID: PMC5938471 DOI: 10.1002/ece3.3957] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 01/31/2018] [Accepted: 02/05/2018] [Indexed: 11/20/2022] Open
Abstract
Recent developments in sexual selection theory suggest that on their own, mate preferences can promote the maintenance of sexual trait diversity. However, how mate preferences constrain the permissiveness of sexual trait diversity in different environmental regimes remains an open question. Here, we examine how a range of mate choice parameters affect the permissiveness of sexual trait polymorphism under several selection regimes. We use the null model of sexual selection and show that environments with strong assortative mating significantly increase the permissiveness of sexual trait polymorphism. We show that for a given change in mate choice parameters, the permissiveness of polymorphism changes more in environments with strong natural selection on sexual traits than in environments with weak selection. Sets of nearly stable polymorphic populations with weak assortative mating are more likely to show accidental divergence in sexual traits than sets of populations with strong assortative mating. The permissiveness of sexual trait polymorphism critically depends upon particular combinations of natural selection and mate choice parameters.
Collapse
Affiliation(s)
- Aditya Ponkshe
- Centre for Integrative Ecology School of Life & Environmental Sciences Deakin University Waurn Ponds Vic. Australia
| | - John A Endler
- Centre for Integrative Ecology School of Life & Environmental Sciences Deakin University Waurn Ponds Vic. Australia
| |
Collapse
|
14
|
Pérez i de Lanuza G, Ábalos J, Bartolomé A, Font E. Through the eye of a lizard: hue discrimination in a lizard with ventral polymorphic coloration. J Exp Biol 2018; 221:jeb.169565. [DOI: 10.1242/jeb.169565] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Accepted: 01/18/2018] [Indexed: 12/19/2022]
Abstract
Colour polymorphisms are thought to be maintained by complex evolutionary processes some of which require that the colours of the alternative morphs function as chromatic signals to conspecifics. Unfortunately, a key aspect of this hypothesis has rarely been studied: whether the study species perceives its own colour variation as discrete rather than continuous. The European common wall lizard (Podarcis muralis) presents a striking colour polymorphism: the ventral surface of adults of both sexes may be coloured orange, white, yellow, or with a mosaic of scales combining two colours (orange-white, orange-yellow). Here we use a discrimination learning paradigm to test if P. muralis is capable of discriminating colour stimuli designed to match the ventral colours of conspecifics. We trained 20 lizards to eat from colour-coded wells bored in wooden blocks. Blocks had four colour-coded wells (orange, white, yellow, and an achromatic control), but only one contained food (mealworm larvae). After six trials, the lizards performed significantly better than expected by chance, showing a decrease in both the number of wells explored and the latency to finding the food. Using visual modelling techniques we found that, based on their spectral properties and the lizards’ cone sensitivities, the ventral colours of P. muralis correspond to discrete rather than continuous colour categories, and that colour discriminability (i.e. distance in perceptual space) varies depending on the morphs compared, which may have implications for signal detection and discrimination. These results suggest that P. muralis can discriminate hue differences matching their own ventral colour variation.
Collapse
Affiliation(s)
- Guillem Pérez i de Lanuza
- CIBIO/InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos da Universidade do Porto, Portugal
| | - Javier Ábalos
- CIBIO/InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos da Universidade do Porto, Portugal
- Ethology Lab, Instituto Cavanilles de Biodiversidad y Biología Evolutiva, Universitat de València, Spain
| | - Alicia Bartolomé
- CIBIO/InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos da Universidade do Porto, Portugal
- Ethology Lab, Instituto Cavanilles de Biodiversidad y Biología Evolutiva, Universitat de València, Spain
| | - Enrique Font
- Ethology Lab, Instituto Cavanilles de Biodiversidad y Biología Evolutiva, Universitat de València, Spain
| |
Collapse
|
15
|
White TE, Kemp DJ. Colour polymorphic lures exploit innate preferences for spectral versus luminance cues in dipteran prey. BMC Evol Biol 2017; 17:191. [PMID: 28806928 PMCID: PMC5557064 DOI: 10.1186/s12862-017-1043-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Accepted: 08/08/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Theory predicts that colour polymorphism may be favored by variation in the visual context under which signals are perceived. The context encompasses all environmental determinants of light availability and propagation, but also the dynamics of perception in receivers. Color vision involves the neural separation of information into spectral versus luminance channels, which often differentially guide specific tasks. Here we explicitly tested whether this discrete perceptual basis contributes to the maintenance of polymorphism in a prey-luring system. The orb-weaving spider Gasteracantha fornicata is known to attract a broad community of primarily dipteran prey due to their conspicuous banded dorsal signal. They occur in two morphs ("white" and "yellow") which should, respectively, generate greater luminance and color contrast in the dipteran eye. Given that arthropods often rely upon luminance-versus-spectral cues for relatively small-versus-large stimulus detection, we predicted a switch in relative attractiveness among morphs according to apparent spider size. RESULTS Our experimental tests used colour-naïve individuals of two known prey species (Drosophila hydei and Musca domestica) in replicate Y-maze choice trials designed to manipulate the apparent size of spider models via the distance at which they are viewed. Initial trials confirmed that flies were attracted to each G. fornicata morph in single presentations. When given a simultaneous choice between morphs against a viewing background typical of those encountered in nature, flies exhibited no preference regardless of the visual angle subtended by models. However, when backgrounds were adjusted to nearer the extremes of those of each morph in the wild, flies were more attracted by white morphs when presented at longer range (consistent with a reliance on achromatic cues), yet were unbiased in their close-range choice. CONCLUSION While not fully consistent with predictions (given the absence of a differential preference for stimuli at close range), our results demonstrate an effect of apparent stimulus size upon relative morph attractiveness in the direction anticipated from present knowledge of fly visual ecology. This implies the potential tuning of G. fornicata morph signal structure according to a perceptual feature that is likely common across their breadth of arthropod prey, and complements recent observational work in suggesting a candidate mechanism for the maintenance of deceptive polymorphism through the exploitation of different visual channels in prey.
Collapse
Affiliation(s)
- Thomas E White
- Department of Biological Science, Macquarie University, Sydney, 2109, Australia.
| | - Darrell J Kemp
- Department of Biological Science, Macquarie University, Sydney, 2109, Australia
| |
Collapse
|
16
|
Brock CD, Cummings ME, Bolnick DI. Phenotypic plasticity drives a depth gradient in male conspicuousness in threespine stickleback,Gasterosteus aculeatus. Evolution 2017; 71:2022-2036. [DOI: 10.1111/evo.13282] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Accepted: 05/04/2017] [Indexed: 01/04/2023]
Affiliation(s)
- Chad D. Brock
- Department of Integrative Biology; University of Texas at Austin; Texas 78712
- Biodiversity Institute and the Department of Botany; University of Wyoming; Laramie Wyoming 82071
| | - Molly E. Cummings
- Department of Integrative Biology; University of Texas at Austin; Texas 78712
| | - Daniel I. Bolnick
- Department of Integrative Biology; University of Texas at Austin; Texas 78712
| |
Collapse
|
17
|
Pérez i de Lanuza G, Carretero MA, Font E. Intensity of male‐male competition predicts morph diversity in a color polymorphic lizard. Evolution 2017; 71:1832-1840. [DOI: 10.1111/evo.13256] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2016] [Revised: 04/01/2017] [Accepted: 04/13/2017] [Indexed: 01/28/2023]
Affiliation(s)
- Guillem Pérez i de Lanuza
- CIBIO Research Centre in Biodiversity and Genetic Resources, InBIOUniversidade do Porto Campus de Vairão, Rua Padre Armando Quintas, 7 4485–661 Vairão, Vila do Conde Portugal
- Cavanilles Institute of Biodiversity and Evolutionary BiologyUniversity of Valencia. APDO 22085 46071 València Spain
| | - Miguel A. Carretero
- CIBIO Research Centre in Biodiversity and Genetic Resources, InBIOUniversidade do Porto Campus de Vairão, Rua Padre Armando Quintas, 7 4485–661 Vairão, Vila do Conde Portugal
| | - Enrique Font
- Cavanilles Institute of Biodiversity and Evolutionary BiologyUniversity of Valencia. APDO 22085 46071 València Spain
| |
Collapse
|
18
|
Svensson EI. Back to basics: using colour polymorphisms to study evolutionary processes. Mol Ecol 2017; 26:2204-2211. [DOI: 10.1111/mec.14025] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Revised: 01/10/2017] [Accepted: 01/10/2017] [Indexed: 12/16/2022]
Affiliation(s)
- Erik I. Svensson
- Evolutionary Ecology Unit; Department of Biology; Lund University; SE-223 62 Lund Sweden
| |
Collapse
|
19
|
Nattero J, Pita S, Calleros L, Crocco L, Panzera Y, Rodríguez CS, Panzera F. Morphological and Genetic Differentiation within the Southernmost Vector of Chagas Disease: Triatoma patagonica (Hemiptera - Reduviidae). PLoS One 2016; 11:e0168853. [PMID: 28005972 PMCID: PMC5179239 DOI: 10.1371/journal.pone.0168853] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Accepted: 12/07/2016] [Indexed: 11/18/2022] Open
Abstract
The epidemiological importance of Chagas disease vectors largely depends on their spreading ability and adaptation to domestic habitats. Triatoma patagonica is a secondary vector of Chagas disease endemic of Argentina, and it has been found colonizing domiciles and most commonly peridomiciliary structures in several Argentine provinces and morphological variation along its distribution range have been described. To asses if population differentiation represents geographic variants or true biological species, multiple genetic and phenotypic approaches and laboratory cross-breeding were performed in T. patagonica peridomestic populations. Analyses of chromatic variation of forewings, their size and the content of C-heterochromatin on chromosomes revealed that populations are structured following a North-South latitudinal variation. Cytochrome c oxidase I mitochondrial gene (COI) nucleotide analysis showed a mean genetic distance of 5.2% between the most distant populations. The cross-breeding experiments suggest a partial reproductive isolation between some populations with 40% of couples not laying eggs and low hatching efficiency. Our findings reveal phenotypic and genetic variations that suggest an incipient differentiation processes among T. patagonica populations with a pronounced phenotypic and genetic divergence between the most distant populations. The population differentiation here reported is probably related to differential environmental conditions and it could reflect the occurrence of an incipient speciation process in T. patagonica.
Collapse
Affiliation(s)
- Julieta Nattero
- Cátedra de Introducción a la Biología, Facultad de Ciencias Exactas Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas -IIByT (CONICET—Universidad Nacional de Córdoba). Avda. Vélez Sarsfield, piso 2, Córdoba, Argentina
- Present address: Laboratorio de Eco-Epidemiología, Instituto de Ecología, Genética y Evolución de Buenos Aires, CONICET, EGE, FCEyN, UBA, Intendente Güiraldes 2160—Ciudad Universitaria—Pabellón 2, Buenos Aires, Argentina
- * E-mail: (JN); (FP)
| | - Sebastián Pita
- Sección Genética Evolutiva, Facultad de Ciencias, Universidad de la República. Iguá, Montevideo, Uruguay
| | - Lucía Calleros
- Sección Genética Evolutiva, Facultad de Ciencias, Universidad de la República. Iguá, Montevideo, Uruguay
| | - Liliana Crocco
- Cátedra de Introducción a la Biología, Facultad de Ciencias Exactas Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas -IIByT (CONICET—Universidad Nacional de Córdoba). Avda. Vélez Sarsfield, piso 2, Córdoba, Argentina
| | - Yanina Panzera
- Sección Genética Evolutiva, Facultad de Ciencias, Universidad de la República. Iguá, Montevideo, Uruguay
| | - Claudia S. Rodríguez
- Cátedra de Introducción a la Biología, Facultad de Ciencias Exactas Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas -IIByT (CONICET—Universidad Nacional de Córdoba). Avda. Vélez Sarsfield, piso 2, Córdoba, Argentina
| | - Francisco Panzera
- Sección Genética Evolutiva, Facultad de Ciencias, Universidad de la República. Iguá, Montevideo, Uruguay
- * E-mail: (JN); (FP)
| |
Collapse
|
20
|
Lackey ACR, Boughman JW. Evolution of reproductive isolation in stickleback fish. Evolution 2016; 71:357-372. [PMID: 27901265 DOI: 10.1111/evo.13114] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Revised: 10/15/2016] [Accepted: 10/24/2016] [Indexed: 12/21/2022]
Abstract
To understand how new species form and what causes their collapse, we examined how reproductive isolation evolves during the speciation process, considering species pairs with little to extensive divergence, including a recently collapsed pair. We estimated many reproductive barriers in each of five sets of stickleback fish species pairs using our own data and decades of previous work. We found that the types of barriers important early in the speciation process differ from those important late. Two premating barriers-habitat and sexual isolation-evolve early in divergence and remain two of the strongest barriers throughout speciation. Premating isolation evolves before postmating isolation, and extrinsic isolation is far stronger than intrinsic. Completing speciation, however, may require postmating intrinsic incompatibilities. Reverse speciation in one species pair was characterized by significant loss of sexual isolation. We present estimates of barrier strengths before and after collapse of a species pair; such detail regarding the loss of isolation has never before been documented. Additionally, despite significant asymmetries in individual barriers, which can limit speciation, total isolation was essentially symmetric between species. Our study provides important insight into the order of barrier evolution and the relative importance of isolating barriers during speciation and tests fundamental predictions of ecological speciation.
Collapse
Affiliation(s)
- Alycia C R Lackey
- Department of Integrative Biology, Michigan State University, East Lansing, Michigan.,Ecology, Evolutionary Biology, and Behavior Program, Michigan State University, East Lansing, Michigan.,BEACON Center for the Study of Evolution in Action, Michigan State University, East Lansing, Michigan.,Department of Biological Sciences, Watershed Studies Institute, Murray State University, 2112 Biology Building, Murray, State University, Murray, Kentucky, 42071
| | - Janette W Boughman
- Department of Integrative Biology, Michigan State University, East Lansing, Michigan.,Ecology, Evolutionary Biology, and Behavior Program, Michigan State University, East Lansing, Michigan.,BEACON Center for the Study of Evolution in Action, Michigan State University, East Lansing, Michigan
| |
Collapse
|
21
|
Pérez i de Lanuza G, Font E, Carretero MÁ. Colour assortative pairing in a colour polymorphic lizard is independent of population morph diversity. Naturwissenschaften 2016; 103:82. [DOI: 10.1007/s00114-016-1407-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Revised: 09/06/2016] [Accepted: 09/09/2016] [Indexed: 11/29/2022]
|
22
|
Marques DA, Lucek K, Haesler MP, Feller AF, Meier JI, Wagner CE, Excoffier L, Seehausen O. Genomic landscape of early ecological speciation initiated by selection on nuptial colour. Mol Ecol 2016; 26:7-24. [DOI: 10.1111/mec.13774] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Revised: 06/30/2016] [Accepted: 07/14/2016] [Indexed: 12/12/2022]
Affiliation(s)
- David Alexander Marques
- Institute of Ecology & Evolution; University of Bern; Bern Switzerland
- Eawag: Swiss Federal Institute of Aquatic Science and Technology; Kastanienbaum Switzerland
| | - Kay Lucek
- Institute of Ecology & Evolution; University of Bern; Bern Switzerland
- Eawag: Swiss Federal Institute of Aquatic Science and Technology; Kastanienbaum Switzerland
- University of Sheffield; Sheffield UK
| | - Marcel Philipp Haesler
- Institute of Ecology & Evolution; University of Bern; Bern Switzerland
- Eawag: Swiss Federal Institute of Aquatic Science and Technology; Kastanienbaum Switzerland
| | - Anna Fiona Feller
- Institute of Ecology & Evolution; University of Bern; Bern Switzerland
- Eawag: Swiss Federal Institute of Aquatic Science and Technology; Kastanienbaum Switzerland
| | - Joana Isabel Meier
- Institute of Ecology & Evolution; University of Bern; Bern Switzerland
- Eawag: Swiss Federal Institute of Aquatic Science and Technology; Kastanienbaum Switzerland
| | - Catherine E. Wagner
- Institute of Ecology & Evolution; University of Bern; Bern Switzerland
- Eawag: Swiss Federal Institute of Aquatic Science and Technology; Kastanienbaum Switzerland
- Department of Botany, Biodiversity Institute; University of Wyoming; Laramie WY USA
| | - Laurent Excoffier
- Institute of Ecology & Evolution; University of Bern; Bern Switzerland
- Swiss Institute of Bioinformatics; Lausanne Switzerland
| | - Ole Seehausen
- Institute of Ecology & Evolution; University of Bern; Bern Switzerland
- Eawag: Swiss Federal Institute of Aquatic Science and Technology; Kastanienbaum Switzerland
| |
Collapse
|
23
|
White TE, Kemp DJ. Color polymorphic lures target different visual channels in prey. Evolution 2016; 70:1398-408. [DOI: 10.1111/evo.12948] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Revised: 04/09/2016] [Accepted: 04/28/2016] [Indexed: 11/29/2022]
Affiliation(s)
- Thomas E. White
- Department of Biological Science Macquarie University North Ryde 2109 Australia
| | - Darrell J. Kemp
- Department of Biological Science Macquarie University North Ryde 2109 Australia
| |
Collapse
|
24
|
Bloch NI. Evolution of opsin expression in birds driven by sexual selection and habitat. Proc Biol Sci 2015; 282:20142321. [PMID: 25429020 DOI: 10.1098/rspb.2014.2321] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Theories of sexual and natural selection predict coevolution of visual perception with conspecific colour and/or the light environment animals occupy. One way to test these theories is to focus on the visual system, which can be achieved by studying the opsin-based visual pigments that mediate vision. Birds vary greatly in colour, but opsin gene coding sequences and associated visual pigment spectral sensitivities are known to be rather invariant across birds. Here, I studied expression of the four cone opsin genes (Lws, Rh2, Sws2 and Sws1) in 16 species of New World warblers (Parulidae). I found levels of opsin expression vary both across species and between the sexes. Across species, female, but not male Sws2 expression is associated with an index of sexual selection, plumage dichromatism. This fits predictions of classic sexual selection models, in which the sensory system changes in females, presumably impacting female preference, and co-evolves with male plumage. Expression of the opsins at the extremes of the light spectrum, Lws and Uvs, correlates with the inferred light environment occupied by the different species. Unlike opsin spectral tuning, regulation of opsin gene expression allows for fast adaptive evolution of the visual system in response to natural and sexual selection, and in particular, sex-specific selection pressures.
Collapse
Affiliation(s)
- Natasha I Bloch
- Department of Ecology and Evolution, University of Chicago, Chicago, IL, USA
| |
Collapse
|
25
|
Pérez i de Lanuza G, Font E. Differences in conspicuousness between alternative color morphs in a polychromatic lizard. Behav Ecol 2015. [DOI: 10.1093/beheco/arv075] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
|
26
|
|
27
|
Tsubaki Y, Okuyama H. Adaptive loss of color polymorphism and character displacements in sympatric Mnais damselflies. Evol Ecol 2015. [DOI: 10.1007/s10682-015-9778-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
28
|
Chang CH, Shao YT, Fu WC, Anraku K, Lin YS, Yan HY. Differentiation of visual spectra and nuptial colorations of two Paratanakia himantegus subspecies (Cyprinoidea: Acheilognathidae) in response to the distinct photic conditions of their habitats. Zool Stud 2015; 54:e43. [PMID: 31966130 DOI: 10.1186/s40555-015-0121-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Accepted: 05/06/2015] [Indexed: 11/10/2022]
Abstract
BACKGROUND Vision, an important sensory modality of many animals, exhibits plasticity in that it adapts to environmental conditions to maintain its sensory efficiency. Nuptial coloration is used to attract mates and hence should be tightly coupled to vision. In Taiwan, two closely related bitterlings (Paratanakia himantegus himantegus and Paratanakia himantegus chii) with different male nuptial colorations reside in different habitats. We compared the visual spectral sensitivities of these subspecies with the ambient light spectra of their habitats to determine whether their visual abilities correspond with photic parameters and correlate with nuptial colorations. RESULTS Theelectroretinogram (ERG) results revealed that the relative spectral sensitivity of P.h. himantegus was higher at 670 nm, but lower at 370 nm, than the sensitivity of P. h. chii. Both bitterlings could perceive and reflect UV light, but the UV reflection patterns differed between genders. Furthermore, the relative irradiance intensity of the light spectra in the habitat of P. h. himantegus was higher at long wavelengths (480-700 nm), but lower at short wavelengths (350-450 nm), than the light spectra in the habitats of P. h.chii. CONCLUSIONS Two phylogenetically closely related bitterlings, P. h. himantegus and P. h. chii, dwell in different waters and exhibit different nuptial colorations and spectral sensitivities, which may be the results of speciation by sensory drive. Sensory ability and signal diversity accommodating photic environment may promote diversity of bitterling fishes. UV light was demonstrated to be a possible component of bitterling visual communication. The UV cue may assist bitterlings in genderidentification.
Collapse
Affiliation(s)
- Chia-Hao Chang
- Department of Biological Science and Technology, National Chiao Tung University, Hsinchu, Taiwan.,Department of Biology, St. Louis University, St. Louis, MO, USA
| | - Yi Ta Shao
- Sensory Physiology Laboratory, Marine Research Station, Academia Sinica, I-Lan, Taiwan.,Present Address: Institute of Marine Biology, National Taiwan Ocean University, Keelung, Taiwan
| | - Wen-Chung Fu
- Sensory Physiology Laboratory, Marine Research Station, Academia Sinica, I-Lan, Taiwan
| | - Kazuhiko Anraku
- Faculty of Fisheries, Kagoshima University, Kagoshima, Japan
| | - Yeong-Shin Lin
- Department of Biological Science and Technology, National Chiao Tung University, Hsinchu, Taiwan.,Institute of Bioinformatics and Systems Biology, National Chiao Tung University, Hsinchu, Taiwan
| | - Hong Young Yan
- Sensory Physiology Laboratory, Marine Research Station, Academia Sinica, I-Lan, Taiwan.,Hanse-Wissenschaftskolleg Institute of Advanced Study, Delmenhorst, Germany
| |
Collapse
|
29
|
Bossu CM, Near TJ. Ecological constraint and the evolution of sexual dichromatism in darters. Evolution 2015; 69:1219-31. [PMID: 25824960 DOI: 10.1111/evo.12655] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Accepted: 03/20/2015] [Indexed: 12/30/2022]
Abstract
It is not known how environmental pressures and sexual selection interact to influence the evolution of extravagant male traits. Sexual and natural selection are often viewed as antagonistic forces shaping the evolution of visual signals, where conspicuousness is favored by sexual selection and crypsis is favored by natural selection. Although typically investigated independently, the interaction between natural and sexual selection remains poorly understood. Here, we investigate whether sexual dichromatism evolves stochastically, independent from, or in concert with habitat use in darters, a species-rich lineage of North American freshwater fish. We find the evolution of sexual dichromatism is coupled to habitat use in darter species. Comparative analyses reveal that mid-water darter lineages exhibit a narrow distribution of dichromatism trait space surrounding a low optimum, suggesting a constraint imposed on the evolution of dichromatism, potentially through predator-mediated selection. Alternatively, the transition to benthic habitats coincides with greater variability in the levels of dichromatism that surround a higher optimum, likely due to relaxation of the predator-mediated selection and heterogeneous microhabitat dependent selection regimes. These results suggest a complex interaction of sexual selection with potentially two mechanisms of natural selection, predation and sensory drive, that influence the evolution of diverse male nuptial coloration in darters.
Collapse
Affiliation(s)
- Christen M Bossu
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, Connecticut, 06520.
| | - Thomas J Near
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, Connecticut, 06520
| |
Collapse
|
30
|
Abstract
The extraordinary species richness of freshwater fishes has attracted much research on mechanisms and modes of speciation. We here review research on speciation in freshwater fishes in light of speciation theory, and place this in a context of broad-scale diversity patterns in freshwater fishes. We discuss several major repeated themes in freshwater fish speciation and the speciation mechanisms they are frequently associated with. These include transitions between marine and freshwater habitats, transitions between discrete freshwater habitats, and ecological transitions within habitats, as well as speciation without distinct niche shifts. Major research directions in the years to come include understanding the transition from extrinsic environment-dependent to intrinsic reproductive isolation and its influences on species persistence and understanding the extrinsic and intrinsic constraints to speciation and how these relate to broad-scale diversification patterns through time.
Collapse
Affiliation(s)
- Ole Seehausen
- Division of Aquatic Ecology and Evolution, Institute of Ecology and Evolution, University of Bern, CH-3012 Bern, Switzerland
- Department of Fish Ecology and Evolution, EAWAG Swiss Federal Institute of Aquatic Science and Technology, Center of Ecology, Evolution and Biogeochemistry, 6047 Kastanienbaum, Switzerland
| | - Catherine E. Wagner
- Division of Aquatic Ecology and Evolution, Institute of Ecology and Evolution, University of Bern, CH-3012 Bern, Switzerland
- Department of Fish Ecology and Evolution, EAWAG Swiss Federal Institute of Aquatic Science and Technology, Center of Ecology, Evolution and Biogeochemistry, 6047 Kastanienbaum, Switzerland
| |
Collapse
|
31
|
Deng B, Estes A, Grieb B, Richard D, Hinds B, Hebets E. A male spider's ornamentation polymorphism maintained by opposing selection with two niches. J Theor Biol 2014; 357:103-11. [PMID: 24831413 DOI: 10.1016/j.jtbi.2014.05.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Revised: 04/16/2014] [Accepted: 05/01/2014] [Indexed: 11/24/2022]
Abstract
The Levene mechanism to maintain genotypic polymorphism by opposing selection on genotypes in multiple niches was proposed 60 years ago, and yet no systems were found to satisfy the mechanism's rather restrictive conditions. Reported here is such an example that a wolf spider population lives in a habitat of mixed rocks and leafy litter for which the females are phenotypically indistinguishable and the males have two distinct phenotypes subject to opposing selection with respect to the substrates. Census data is best-fitted to a population genetics model of the Levene type. A majority of the best fit support polymorphism, with many fitted parameter values quantitatively consistent with various laboratory studies on two closely related species.
Collapse
Affiliation(s)
- Bo Deng
- Department of Mathematics, University of Nebraska-Lincoln, United States.
| | - Alex Estes
- Department of Mathematics, University of Nebraska-Lincoln, United States.
| | - Brett Grieb
- School of Biological Sciences, University of Nebraska-Lincoln, United States.
| | - Douglas Richard
- Department of Mathematics, University of Nebraska-Lincoln, United States.
| | - Brittney Hinds
- Department of Mathematics, University of Nebraska-Lincoln, United States.
| | - Eileen Hebets
- School of Biological Sciences, University of Nebraska-Lincoln, United States.
| |
Collapse
|
32
|
Massatti R, Knowles LL. MICROHABITAT DIFFERENCES IMPACT PHYLOGEOGRAPHIC CONCORDANCE OF CODISTRIBUTED SPECIES: GENOMIC EVIDENCE IN MONTANE SEDGES (CAREXL.) FROM THE ROCKY MOUNTAINS. Evolution 2014; 68:2833-46. [DOI: 10.1111/evo.12491] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2014] [Accepted: 06/25/2014] [Indexed: 01/15/2023]
Affiliation(s)
- Rob Massatti
- Department of Ecology and Evolutionary Biology; The University of Michigan; Ann Arbor Michigan 41809
| | - L. Lacey Knowles
- Department of Ecology and Evolutionary Biology; The University of Michigan; Ann Arbor Michigan 41809
| |
Collapse
|
33
|
Hurtado-Gonzales JL, Loew ER, Uy JAC. Variation in the visual habitat may mediate the maintenance of color polymorphism in a poeciliid fish. PLoS One 2014; 9:e101497. [PMID: 24987856 PMCID: PMC4079317 DOI: 10.1371/journal.pone.0101497] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Accepted: 06/06/2014] [Indexed: 12/22/2022] Open
Abstract
The conspicuousness of animal signals is influenced by their contrast against the background. As such, signal conspicuousness will tend to vary in nature because habitats are composed of a mosaic of backgrounds. Variation in attractiveness could result in variation in conspecific mate choice and risk of predation, which, in turn, may create opportunities for balancing selection to maintain distinct polymorphisms. We quantified male coloration, the absorbance spectrum of visual pigments and the photic environment of Poecilia parae, a fish species with five distinct male color morphs: a drab (i.e., grey), a striped, and three colorful (i.e., blue, red and yellow) morphs. Then, using physiological models, we assessed how male color patterns can be perceived in their natural visual habitats by conspecific females and a common cichlid predator, Aequidens tetramerus. Our estimates of chromatic and luminance contrasts suggest that the three most colorful morphs were consistently the most conspicuous across all habitats. However, variation in the visual background resulted in variation in which morph was the most conspicuous to females at each locality. Likewise, the most colorful morphs were the most conspicuous morphs to cichlid predators. If females are able to discriminate between conspicuous prospective mates and those preferred males are also more vulnerable to predation, variable visual habitats could influence the direction and strength of natural and sexual selection, thereby allowing for the persistence of color polymorphisms in natural environments.
Collapse
Affiliation(s)
| | - Ellis R. Loew
- Department of Biomedical Sciences, Cornell University, Ithaca, New York, United States of America
| | - J. Albert C. Uy
- Department of Biology, Syracuse University, Syracuse, New York, United States of America
- Department of Biology, University of Miami, Coral Gables, Florida, United States of America
| |
Collapse
|
34
|
Limeri LB, Morehouse NI. Sensory limitations and the maintenance of colour polymorphisms: viewing the ‘alba’ female polymorphism through the visual system of maleColiasbutterflies. Funct Ecol 2014. [DOI: 10.1111/1365-2435.12244] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Lisa B. Limeri
- Department of Biological Sciences; University of Pittsburgh; Pittsburgh PA 15213 USA
| | - Nathan I. Morehouse
- Department of Biological Sciences; University of Pittsburgh; Pittsburgh PA 15213 USA
| |
Collapse
|
35
|
Kemp DJ, Holmes C, Congdon BC, Edwards W. Color Polymorphism in Spiny Spiders (Gasteracantha fornicata): Testing the Adaptive Significance of a Geographically Clinal Lure. Ethology 2013. [DOI: 10.1111/eth.12172] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Darrell J. Kemp
- Centre for Tropical Environmental Sustainability Science and School of Marine and Tropical Biology; James Cook University; Cairns Qld Australia
- Department of Biological Sciences; Macquarie University; North Ryde NSW Australia
| | - Claire Holmes
- Centre for Tropical Environmental Sustainability Science and School of Marine and Tropical Biology; James Cook University; Cairns Qld Australia
| | - Bradley C. Congdon
- Centre for Tropical Environmental Sustainability Science and School of Marine and Tropical Biology; James Cook University; Cairns Qld Australia
| | - Will Edwards
- Centre for Tropical Environmental Sustainability Science and School of Marine and Tropical Biology; James Cook University; Cairns Qld Australia
| |
Collapse
|
36
|
Secondi J, Okassa M, Sourice S, Théry M. Habitat-Dependent Species Recognition in Hybridizing Newts. Evol Biol 2013. [DOI: 10.1007/s11692-013-9248-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
|
37
|
Blouin-Demers G, Lourdais O, Bouazza A, Verreault C, El Mouden H, Slimani T. Patterns of throat colour variation in Quedenfeldtia trachyblepharus, a high-altitude gecko endemic to the High Atlas Mountains of Morocco. AMPHIBIA-REPTILIA 2013. [DOI: 10.1163/15685381-00002900] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The persistence of marked phenotypic variation within species is evolutionarily puzzling. We uncovered remarkable variation in throat colouration in a high-altitude gecko (Atlas Day Gecko, Quedenfeldtia trachyblepharus) endemic to the High Atlas Mountains of Morocco. Orange, yellow, and white variants were found in approximately equal proportions in both sexes, and in juveniles and adults. The colour variants did not differ in body size or in body condition, but there was some indication that orange males have relatively longer jaws than white or yellow males. The number of mites harboured by an individual was not a function of its sex or of its throat colouration, but larger lizards did harbour more mites. Our data do not support the hypotheses that throat colour variation is due to selection pressures differing between the sexes or through ontogeny, or signals immunocompetence, but offer some support for the hypothesis that throat colour variation signals dominance. Future investigations on the evolution of throat colour variation in this species should use spectrophotometry to obtain finer colour classification and incorporate measures of fitness.
Collapse
Affiliation(s)
| | - Olivier Lourdais
- 2Centre d’Études Biologiques de Chizé, Centre National de la Recherche Scientifique, Villiers en Bois, 79360 France
| | - Abdellah Bouazza
- 3Laboratoire Biodiversité et Dynamique des Écosystèmes, Faculté des Sciences Semlalia, Université Cadi Ayyad, Marrakech, 40 000 Maroc
| | - Catherine Verreault
- 4Parc de la Gatineau, Commission de la Capitale Nationale, Ottawa, Ontario, K1P 1C7 Canada
| | - Hassan El Mouden
- 3Laboratoire Biodiversité et Dynamique des Écosystèmes, Faculté des Sciences Semlalia, Université Cadi Ayyad, Marrakech, 40 000 Maroc
| | - Tahar Slimani
- 3Laboratoire Biodiversité et Dynamique des Écosystèmes, Faculté des Sciences Semlalia, Université Cadi Ayyad, Marrakech, 40 000 Maroc
| |
Collapse
|
38
|
Hancox D, Wilson RS, White CR. Visual habitat geometry predicts relative morph abundance in the colour-polymorphic ornate rainbowfish. Proc Biol Sci 2012; 280:20122377. [PMID: 23222447 DOI: 10.1098/rspb.2012.2377] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
During colour signalling in aquatic environments, the colour of the ambient light, the background against which signals are viewed and signal transmission through the environment can all have profound impacts on the efficacy of a given signal. In colour-polymorphic species, where alternative morphs persist owing to a balance in the natural and sexual selection for each, changes to the visual context can have large effects on the local success and relative abundance of competing phenotypes. The ornate rainbowfish, Rhadinocentrus ornatus, is composed of populations that vary in the relative frequency of red and blue individuals, and inhabit sites that vary in water transmittance from clear (white) to heavily tannin-stained (red-shifted). Using spectroradiometry, we measured the downwelling and sidewelling irradiance, bank radiance and water transmittance of 10 R. ornatus habitats. We found that the relative local abundance of each morph was predicted not by water transmittance but by chromatic differences between the vertical (downwelling light) and horizontal (bank colour) components of the habitat. This visual habitat geometry should increase contrast between the colour signal and background, with large potential to influence the strength of natural and sexual selection in this system.
Collapse
Affiliation(s)
- Daniel Hancox
- School of Biological Sciences, The University of Queensland, St Lucia, Queensland 4072, Australia.
| | | | | |
Collapse
|
39
|
Pérez i de Lanuza G, Font E, Carazo P. Color-assortative mating in a color-polymorphic lacertid lizard. Behav Ecol 2012. [DOI: 10.1093/beheco/ars164] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
|
40
|
Frame AM, Servedio MR. The evolution of preference strength under sensory bias: a role for indirect selection? Ecol Evol 2012; 2:1572-83. [PMID: 22957163 PMCID: PMC3434938 DOI: 10.1002/ece3.273] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2012] [Revised: 04/02/2012] [Accepted: 04/09/2012] [Indexed: 11/06/2022] Open
Abstract
Evidence suggests that female preferences may sometimes arise through sensory bias, and that males may subsequently evolve traits that increase their conspicuousness to females. Here, we ask whether indirect selection, arising through genetic associations (linkage disequilibrium) during the sexual selection that sensory bias imposes, can itself influence the evolution of preference strength. Specifically, we use population genetic models to consider whether or not modifiers of preference strength can spread under different ecological conditions when female mate choice is driven by sensory bias. We focus on male traits that make a male more conspicuous in certain habitats-and thus both more visible to predators and more attractive to females-and examine modifiers of the strength of preference for conspicuous males. We first solve for the rate of spread of a modifier that strengthens preference within an environmentally uniform population; we illustrate that this spread will be extremely slow. Second, we used a series of simulations to consider the role of habitat structure and movement on the evolution of a modifier of preference strength, using male color polymorphisms as a case study. We find that in most cases, indirect selection does not allow the evolution of stronger or weaker preferences for sensory bias. Only in a "two-island" model, where there is restricted migration between different patches that favor different male phenotypes, did we find that preference strength could evolve. The role of indirect selection in the evolution of sensory bias is of particular interest because of ongoing speculation regarding the role of sensory bias in the evolution of reproductive isolation.
Collapse
Affiliation(s)
- Alicia M Frame
- Department of Biology, University of North Carolina at Chapel Hill CB 3280, Chapel Hill, North Carolina 27599
| | | |
Collapse
|
41
|
Wagner CE, McCune AR, Lovette IJ. Recent speciation between sympatric Tanganyikan cichlid colour morphs. Mol Ecol 2012; 21:3283-92. [PMID: 22612462 DOI: 10.1111/j.1365-294x.2012.05607.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Lake Tanganyika, Africa's oldest lake, harbours an impressive diversity of cichlid fishes. Although diversification in its radiating groups is thought to have been initially rapid, cichlids from Lake Tanganyika show little evidence for ongoing speciation. In contrast, examples of recent divergence among sympatric colour morphs are well known in haplochromine cichlids from Lakes Malawi and Victoria. Here, we report genetic evidence for recent divergence between two sympatric Tanganyikan cichlid colour morphs. These Petrochromis morphs share mitochondrial haplotypes, yet microsatellite loci reveal that their sympatric populations form distinct genetic groups. Nuclear divergence between the two morphs is equivalent to that which arises geographically within one of the morphs over short distances and is substantially smaller than that among other sympatric species in this genus. These patterns suggest that these morphs diverged only recently, yet that barriers to gene flow exist which prevent extensive admixture despite their sympatric distribution. The morphs studied here provide an unusual example of active diversification in Lake Tanganyika's generally ancient cichlid fauna and enable comparisons of speciation processes between Lake Tanganyika and other African lakes.
Collapse
Affiliation(s)
- Catherine E Wagner
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY 14853, USA.
| | | | | |
Collapse
|
42
|
Accelerated speciation in colour-polymorphic birds. Nature 2012; 485:631-4. [DOI: 10.1038/nature11050] [Citation(s) in RCA: 140] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2011] [Accepted: 03/21/2012] [Indexed: 11/08/2022]
|
43
|
|
44
|
Hurtado-Gonzales JL, Uy JAC. Intrasexual competition facilitates the evolution of alternative mating strategies in a colour polymorphic fish. BMC Evol Biol 2010; 10:391. [PMID: 21182755 PMCID: PMC3017046 DOI: 10.1186/1471-2148-10-391] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2010] [Accepted: 12/23/2010] [Indexed: 11/10/2022] Open
Abstract
Background Intense competition for access to females can lead to males exploiting different components of sexual selection, and result in the evolution of alternative mating strategies (AMSs). Males of Poecilia parae, a colour polymorphic fish, exhibit five distinct phenotypes: drab-coloured (immaculata), striped (parae), structural-coloured (blue) and carotenoid-based red and yellow morphs. Previous work indicates that immaculata males employ a sneaker strategy, whereas the red and yellow morphs exploit female preferences for carotenoid-based colours. Mating strategies favouring the maintenance of the other morphs remain to be determined. Here, we report the role of agonistic male-male interactions in influencing female mating preferences and male mating success, and in facilitating the evolution of AMSs. Results Our study reveals variation in aggressiveness among P. parae morphs during indirect and direct interactions with sexually receptive females. Two morphs, parae and yellow, use aggression to enhance their mating success (i.e., number of copulations) by 1) directly monopolizing access to females, and 2) modifying female preferences after winning agonistic encounters. Conversely, we found that the success of the drab-coloured immaculata morph, which specializes in a sneak copulation strategy, relies in its ability to circumvent both male aggression and female choice when facing all but yellow males. Conclusions Strong directional selection is expected to deplete genetic variation, yet many species show striking genetically-based polymorphisms. Most studies evoke frequency dependent selection to explain the persistence of such variation. Consistent with a growing body of evidence, our findings suggest that a complex form of balancing selection may alternatively explain the evolution and maintenance of AMSs in a colour polymorphic fish. In particular, this study demonstrates that intrasexual competition results in phenotypically distinct males exhibiting clear differences in their levels of aggression to exclude potential sexual rivals. By being dominant, the more aggressive males are able to circumvent female mating preferences for attractive males, whereas another male type incorporates subordinate behaviours that allow them to circumvent male aggression and female mating preferences. Together, these and previous results indicate that exploiting different aspects of social interactions may allow males to evolve distinct mating strategies and thus the long term maintenance of polymorphisms within populations.
Collapse
|
45
|
Hancox D, Hoskin CJ, Wilson RS. Evening up the score: sexual selection favours both alternatives in the colour-polymorphic ornate rainbowfish. Anim Behav 2010. [DOI: 10.1016/j.anbehav.2010.08.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
46
|
MCKINNON JEFFREYS, PIEROTTI MICHELEER. Colour polymorphism and correlated characters: genetic mechanisms and evolution. Mol Ecol 2010; 19:5101-25. [DOI: 10.1111/j.1365-294x.2010.04846.x] [Citation(s) in RCA: 231] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
|
47
|
Runemark A, Hansson B, Pafilis P, Valakos ED, Svensson EI. Island biology and morphological divergence of the Skyros wall lizard Podarcis gaigeae: a combined role for local selection and genetic drift on color morph frequency divergence? BMC Evol Biol 2010; 10:269. [PMID: 20813033 PMCID: PMC2939580 DOI: 10.1186/1471-2148-10-269] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2009] [Accepted: 09/02/2010] [Indexed: 05/26/2023] Open
Abstract
BACKGROUND Patterns of spatial variation in discrete phenotypic traits can be used to draw inferences about the adaptive significance of traits and evolutionary processes, especially when compared to patterns of neutral genetic variation. Population divergence in adaptive traits such as color morphs can be influenced by both local ecology and stochastic factors such as genetic drift or founder events. Here, we use quantitative color measurements of males and females of Skyros wall lizard, Podarcis gaigeae, to demonstrate that this species is polymorphic with respect to throat color, and the morphs form discrete phenotypic clusters with limited overlap between categories. We use divergence in throat color morph frequencies and compare that to neutral genetic variation to infer the evolutionary processes acting on islet- and mainland populations. RESULTS Geographically close islet- and mainland populations of the Skyros wall lizard exhibit strong divergence in throat color morph frequencies. Population variation in throat color morph frequencies between islets was higher than that between mainland populations, and the effective population sizes on the islets were small (Ne:s < 100). Population divergence (FST) for throat color morph frequencies fell within the neutral FST-distribution estimated from microsatellite markers, and genetic drift could thus not be rejected as an explanation for the pattern. Moreover, for both comparisons among mainland-mainland population pairs and between mainland-islet population pairs, morph frequency divergence was significantly correlated with neutral divergence, further pointing to some role for genetic drift in divergence also at the phenotypic level of throat color morphs. CONCLUSIONS Genetic drift could not be rejected as an explanation for the pattern of population divergence in morph frequencies. In spite of an expected stabilising selection, throat color frequencies diverged in the islet populations. These results suggest that there is an interaction between selection and genetic drift causing divergence even at a phenotypic level in these small, subdivided populations.
Collapse
Affiliation(s)
- Anna Runemark
- Section for Animal Ecology, Ecology Building, Lund University, SE-223 62 Lund, Sweden.
| | | | | | | | | |
Collapse
|
48
|
Schwartz AK, Hendry AP. Testing the influence of local forest canopy clearing on phenotypic variation in Trinidadian guppies. Funct Ecol 2010. [DOI: 10.1111/j.1365-2435.2009.01652.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
49
|
WANG IANJ, SUMMERS KYLE. Genetic structure is correlated with phenotypic divergence rather than geographic isolation in the highly polymorphic strawberry poison-dart frog. Mol Ecol 2010; 19:447-58. [DOI: 10.1111/j.1365-294x.2009.04465.x] [Citation(s) in RCA: 172] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
50
|
FULLER REBECCAC, JOHNSON ASHLEYM. A test for negative frequency-dependent mating success as a function of male colour pattern in the bluefin killifish. Biol J Linn Soc Lond 2009. [DOI: 10.1111/j.1095-8312.2009.01308.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|