1
|
Sil M, Roy A, Bhat HNP, Palden T, Karanth KP, Aravind NA. Role of paleoclimatic and paleohydrological processes in lineage divergence in freshwater organisms: A snippet from lentic genus Pila. Mol Phylogenet Evol 2023; 181:107723. [PMID: 36720420 DOI: 10.1016/j.ympev.2023.107723] [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: 11/18/2021] [Revised: 11/09/2022] [Accepted: 01/24/2023] [Indexed: 01/31/2023]
Abstract
The Indian subcontinent is extremely diverse in terms of its flora and fauna. However, only a handful of studies have aimed to understand the diversity of freshwater invertebrates using multiple lines of evidence in recent times. Here we aimed to estimate the cryptic diversity of two widespread freshwater snail species within the genus Pila (Röding, 1798) and uncover the processes behind lineage diversification in these species. We sequenced mitochondrial and nuclear markers from a comprehensive sampling of specimens from different river basins in India. We implemented an integrative taxonomy approach to delimit the lineages in these groups, employing phylogenetic, geometric morphometric and niche modelling-based methods. Then, we investigated the drivers of lineage divergence in these species using population genetic tools in conjunction with divergence time estimation. We found that both species consist of several genetically and ecologically distinct lineages. The genetic data showed that several of these lineages are restricted to a single or a few river basins. The divergence time estimation analyses indicated that the time frame of divergence within the species coincided with paleohydrological and paleoclimatic events in the Miocene. The diversification was primarily driven by allopatric isolation into different river basins. To conclude, the study sheds light on the complex interaction between the habitat preference of the species and the environment in shaping the diversification patterns in this group.
Collapse
Affiliation(s)
- Maitreya Sil
- Suri Sehgal Centre for Biodiversity and Conservation, Ashoka Trust for Research in Ecology and the Environment (ATREE), Royal Enclave, Srirampura, Jakkur PO, Bangalore 560064, India; National Institute for Science Education and Research, Bhubaneswar 752050, India.
| | - Abhisikta Roy
- Suri Sehgal Centre for Biodiversity and Conservation, Ashoka Trust for Research in Ecology and the Environment (ATREE), Royal Enclave, Srirampura, Jakkur PO, Bangalore 560064, India
| | - H N Poorna Bhat
- Suri Sehgal Centre for Biodiversity and Conservation, Ashoka Trust for Research in Ecology and the Environment (ATREE), Royal Enclave, Srirampura, Jakkur PO, Bangalore 560064, India
| | - Tenzin Palden
- Centre for Ecological Sciences, Indian Institute of Science, Malleshwaram, Bangalore 560012, India
| | - K Praveen Karanth
- Centre for Ecological Sciences, Indian Institute of Science, Malleshwaram, Bangalore 560012, India
| | - N A Aravind
- Suri Sehgal Centre for Biodiversity and Conservation, Ashoka Trust for Research in Ecology and the Environment (ATREE), Royal Enclave, Srirampura, Jakkur PO, Bangalore 560064, India; Yenepoya Research Centre, Yenepoya University, Derlakatte, Mangalore, India.
| |
Collapse
|
2
|
Tamagawa K, Yoshida K, Ohrui S, Takahashi Y. Population transcriptomics reveals the effect of gene flow on the evolution of range limits. Sci Rep 2022; 12:1318. [PMID: 35079049 PMCID: PMC8789792 DOI: 10.1038/s41598-022-05248-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 01/10/2022] [Indexed: 11/17/2022] Open
Abstract
One of the most important questions in evolutionary biology is how the spatial distribution of species is limited. Asymmetric gene flow from core populations is suggested to increase the number of poorly adapted immigrants in the populations at the range edge. Genetic load due to migration, i.e., migration load, should prevent adaptation to the local habitat, leading to decreases in distribution range via local extinction or the limiting range expansion. However, few experimental studies have examined the effects of immigration on fitness and natural selection within recipient populations. To investigate the influence of migration load on the evolution of distribution range, we performed field and laboratory observations as well as population transcriptomics for the common river snail, Semisulcospira reiniana. This species meets the conditions that migration from source populations can prevent local adaptation in a sink population because they inhabit the broader range of environments, including middle/upper reaches of a river and estuaries within a single river and they may be more vulnerable to being swept away by water currents due to lowered spontaneous (upward) locomotion activity. We found that river steepness was related to the lower distribution limit of S. reiniana, with a narrower distribution range in the steeper river. Population transcriptomic analysis showed that gene flow was heavily asymmetric from the upstream populations to downstream ones in the steep river, suggesting a greater migration load in the steep river. The number of genes putatively involved in adaptation to the local habitat was lower in the steep river than in the gentle river. Gene expression profiles suggested that individuals achieve better local adaptation in the gentle river. Laboratory experiments suggested that evolutionary differences in salinity tolerance among local populations were only found in the gentle river. Our results consistent with the hypothesis that migration load owing to asymmetric gene flow disturbs local adaptation and restricts the distribution range of river snails.
Collapse
Affiliation(s)
- Katsunori Tamagawa
- Graduate School of Science, Chiba University, 1-33, Yayoi, Inage, Chiba, 263-8522, Japan.
- Graduate School of Life Sciences, Tohoku University, 6-3, Aoba, Aramaki, Sendai, Miyagi, 980-8578, Japan.
| | - Kotone Yoshida
- Graduate School of Science and Engineering, Chiba University, 1-33, Yayoi, Inage, Chiba, 263-8522, Japan
| | - Shiori Ohrui
- Graduate School of Science and Engineering, Chiba University, 1-33, Yayoi, Inage, Chiba, 263-8522, Japan
| | - Yuma Takahashi
- Graduate School of Science, Chiba University, 1-33, Yayoi, Inage, Chiba, 263-8522, Japan.
| |
Collapse
|
3
|
Jofre GI, Rosenthal GG. A narrow window for geographic cline analysis using genomic data: Effects of age, drift, and migration on error rates. Mol Ecol Resour 2021; 21:2278-2287. [PMID: 33979028 DOI: 10.1111/1755-0998.13428] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Revised: 05/04/2021] [Accepted: 05/07/2021] [Indexed: 01/11/2023]
Abstract
The use of genomic and phenotypic data to scan for outliers is a mainstay for studies of hybridization and speciation. Geographic cline analysis of natural hybrid zones is widely used to identify putative signatures of selection by detecting deviations from baseline patterns of introgression. As with other outlier-based approaches, demographic histories can make neutral regions appear to be under selection and vice versa. In this study, we use a forward-time individual-based simulation approach to evaluate the robustness of geographic cline analysis under different evolutionary scenarios. We modelled multiple stepping-stone hybrid zones with distinct age, deme sizes, and migration rates, and evolving under different types of selection. We found that drift distorts cline shapes and increases false positive rates for signatures of selection. This effect increases with hybrid zone age, particularly if migration between demes is low. Drift can also distort the signature of deleterious effects of hybridization, with genetic incompatibilities and particularly underdominance prone to spurious typing as adaptive introgression. Our results suggest that geographic clines are most useful for outlier analysis in young hybrid zones with large populations of hybrid individuals. Current approaches may overestimate adaptive introgression and underestimate selection against maladaptive genotypes.
Collapse
Affiliation(s)
- Gaston I Jofre
- Department of Biology, Texas A&M University, TAMU, College Station, TX, USA.,Centro de Investigaciones Cientıficas de las Huastecas "Aguazarca", Calnali Hidalgo, Mexico.,Department of Biology, University of North Carolina, Chapel Hill, NC, USA
| | - Gil G Rosenthal
- Department of Biology, Texas A&M University, TAMU, College Station, TX, USA.,Centro de Investigaciones Cientıficas de las Huastecas "Aguazarca", Calnali Hidalgo, Mexico
| |
Collapse
|
4
|
Haenel Q, Oke KB, Laurentino TG, Hendry AP, Berner D. Clinal genomic analysis reveals strong reproductive isolation across a steep habitat transition in stickleback fish. Nat Commun 2021; 12:4850. [PMID: 34381033 PMCID: PMC8358029 DOI: 10.1038/s41467-021-25039-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Accepted: 07/20/2021] [Indexed: 11/29/2022] Open
Abstract
How ecological divergence causes strong reproductive isolation between populations in close geographic contact remains poorly understood at the genomic level. We here study this question in a stickleback fish population pair adapted to contiguous, ecologically different lake and stream habitats. Clinal whole-genome sequence data reveal numerous genome regions (nearly) fixed for alternative alleles over a distance of just a few hundred meters. This strong polygenic adaptive divergence must constitute a genome-wide barrier to gene flow because a steep cline in allele frequencies is observed across the entire genome, and because the cline center closely matches the habitat transition. Simulations confirm that such strong divergence can be maintained by polygenic selection despite high dispersal and small per-locus selection coefficients. Finally, comparing samples from near the habitat transition before and after an unusual ecological perturbation demonstrates the fragility of the balance between gene flow and selection. Overall, our study highlights the efficacy of divergent selection in maintaining reproductive isolation without physical isolation, and the analytical power of studying speciation at a fine eco-geographic and genomic scale.
Collapse
Affiliation(s)
- Quiterie Haenel
- Department of Environmental Sciences, Zoology, University of Basel, Basel, Switzerland.
| | - Krista B Oke
- College of Fisheries and Ocean Sciences, University of Alaska Fairbanks, Juneau, AK, USA
- Redpath Museum and Department of Biology, McGill University, Montréal, QC, Canada
| | - Telma G Laurentino
- Department of Environmental Sciences, Zoology, University of Basel, Basel, Switzerland
| | - Andrew P Hendry
- Redpath Museum and Department of Biology, McGill University, Montréal, QC, Canada
| | - Daniel Berner
- Department of Environmental Sciences, Zoology, University of Basel, Basel, Switzerland.
| |
Collapse
|
5
|
Paccard A, Hanson D, Stuart YE, von Hippel FA, Kalbe M, Klepaker T, Skúlason S, Kristjánsson BK, Bolnick DI, Hendry AP, Barrett RDH. Repeatability of Adaptive Radiation Depends on Spatial Scale: Regional Versus Global Replicates of Stickleback in Lake Versus Stream Habitats. J Hered 2021; 111:43-56. [PMID: 31690947 DOI: 10.1093/jhered/esz056] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Accepted: 09/30/2019] [Indexed: 11/13/2022] Open
Abstract
The repeatability of adaptive radiation is expected to be scale-dependent, with determinism decreasing as greater spatial separation among "replicates" leads to their increased genetic and ecological independence. Threespine stickleback (Gasterosteus aculeatus) provide an opportunity to test whether this expectation holds for the early stages of adaptive radiation-their diversification in freshwater ecosystems has been replicated many times. To better understand the repeatability of that adaptive radiation, we examined the influence of geographic scale on levels of parallel evolution by quantifying phenotypic and genetic divergence between lake and stream stickleback pairs sampled at regional (Vancouver Island) and global (North America and Europe) scales. We measured phenotypes known to show lake-stream divergence and used reduced representation genome-wide sequencing to estimate genetic divergence. We assessed the scale dependence of parallel evolution by comparing effect sizes from multivariate models and also the direction and magnitude of lake-stream divergence vectors. At the phenotypic level, parallelism was greater at the regional than the global scale. At the genetic level, putative selected loci showed greater lake-stream parallelism at the regional than the global scale. Generally, the level of parallel evolution was low at both scales, except for some key univariate traits. Divergence vectors were often orthogonal, highlighting possible ecological and genetic constraints on parallel evolution at both scales. Overall, our results confirm that the repeatability of adaptive radiation decreases at increasing spatial scales. We suggest that greater environmental heterogeneity at larger scales imposes different selection regimes, thus generating lower repeatability of adaptive radiation at larger spatial scales.
Collapse
Affiliation(s)
- Antoine Paccard
- Redpath Museum and Department of Biology, McGill University, Montreal, Canada
| | - Dieta Hanson
- Redpath Museum and Department of Biology, McGill University, Montreal, Canada
| | - Yoel E Stuart
- Department of Integrative Biology, University of Texas at Austin, Austin, TX
| | - Frank A von Hippel
- Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ
| | - Martin Kalbe
- Department of Evolutionary Ecology, Max Planck Institute for Evolutionary Biology, Plön, Germany
| | - Tom Klepaker
- University of Bergen, Department of Biology, Bergen, Norway
| | - Skúli Skúlason
- Department of Aquaculture and Fish Biology, Hólar University College, Sauðárkrókur, Iceland
| | - Bjarni K Kristjánsson
- Department of Aquaculture and Fish Biology, Hólar University College, Sauðárkrókur, Iceland
| | - Daniel I Bolnick
- Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT
| | - Andrew P Hendry
- Redpath Museum and Department of Biology, McGill University, Montreal, Canada
| | - Rowan D H Barrett
- Redpath Museum and Department of Biology, McGill University, Montreal, Canada
| |
Collapse
|
6
|
Ducret V, Richards AJ, Videlier M, Scalvenzi T, Moore KA, Paszkiewicz K, Bonneaud C, Pollet N, Herrel A. Transcriptomic analysis of the trade-off between endurance and burst-performance in the frog Xenopus allofraseri. BMC Genomics 2021; 22:204. [PMID: 33757428 PMCID: PMC7986297 DOI: 10.1186/s12864-021-07517-1] [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: 09/17/2020] [Accepted: 03/08/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Variation in locomotor capacity among animals often reflects adaptations to different environments. Despite evidence that physical performance is heritable, the molecular basis of locomotor performance and performance trade-offs remains poorly understood. In this study we identify the genes, signaling pathways, and regulatory processes possibly responsible for the trade-off between burst performance and endurance observed in Xenopus allofraseri, using a transcriptomic approach. RESULTS We obtained a total of about 121 million paired-end reads from Illumina RNA sequencing and analyzed 218,541 transcripts obtained from a de novo assembly. We identified 109 transcripts with a significant differential expression between endurant and burst performant individuals (FDR ≤ 0.05 and logFC ≥2), and blast searches resulted in 103 protein-coding genes. We found major differences between endurant and burst-performant individuals in the expression of genes involved in the polymerization and ATPase activity of actin filaments, cellular trafficking, proteoglycans and extracellular proteins secreted, lipid metabolism, mitochondrial activity and regulators of signaling cascades. Remarkably, we revealed transcript isoforms of key genes with functions in metabolism, apoptosis, nuclear export and as a transcriptional corepressor, expressed in either burst-performant or endurant individuals. Lastly, we find two up-regulated transcripts in burst-performant individuals that correspond to the expression of myosin-binding protein C fast-type (mybpc2). This suggests the presence of mybpc2 homoeologs and may have been favored by selection to permit fast and powerful locomotion. CONCLUSION These results suggest that the differential expression of genes belonging to the pathways of calcium signaling, endoplasmic reticulum stress responses and striated muscle contraction, in addition to the use of alternative splicing and effectors of cellular activity underlie locomotor performance trade-offs. Ultimately, our transcriptomic analysis offers new perspectives for future analyses of the role of single nucleotide variants, homoeology and alternative splicing in the evolution of locomotor performance trade-offs.
Collapse
Affiliation(s)
- Valérie Ducret
- UMR 7179 MECADEV, C.N.R.S/M.N.H.N., Département Adaptations du Vivant, 55 Rue Buffon, 75005, Paris, France.
| | - Adam J Richards
- Station d'Ecologie Expérimentale du CNRS, USR 2936, 09200, Moulis, France
| | - Mathieu Videlier
- Functional Ecology Lab, Department of Biology, University of Ottawa, 30 Marie Curie, Ottawa, ON, K1N 6N5, Canada
| | - Thibault Scalvenzi
- Evolution, Génomes, Comportement & Ecologie, Université Paris-Saclay, CNRS, IRD, 91198, Gif-sur-Yvette, France
| | - Karen A Moore
- Exeter Sequencing Service, College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4QD, UK
| | - Konrad Paszkiewicz
- Exeter Sequencing Service, College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4QD, UK
| | - Camille Bonneaud
- Station d'Ecologie Expérimentale du CNRS, USR 2936, 09200, Moulis, France
- Centre for Ecology & Conservation, College of Life and Environmental Sciences, University of Exeter, Penryn, Cornwall, UK
| | - Nicolas Pollet
- Evolution, Génomes, Comportement & Ecologie, Université Paris-Saclay, CNRS, IRD, 91198, Gif-sur-Yvette, France
| | - Anthony Herrel
- Station d'Ecologie Expérimentale du CNRS, USR 2936, 09200, Moulis, France
- Evolutionary Morphology of Vertebrates, Ghent University, B-9000, Ghent, Belgium
| |
Collapse
|
7
|
Reid JM, Arcese P, Nietlisbach P, Wolak ME, Muff S, Dickel L, Keller LF. Immigration counter-acts local micro-evolution of a major fitness component: Migration-selection balance in free-living song sparrows. Evol Lett 2021; 5:48-60. [PMID: 33552535 PMCID: PMC7857281 DOI: 10.1002/evl3.214] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 11/28/2020] [Accepted: 12/18/2020] [Indexed: 01/11/2023] Open
Abstract
Ongoing adaptive evolution, and resulting “evolutionary rescue” of declining populations, requires additive genetic variation in fitness. Such variation can be increased by gene flow resulting from immigration, potentially facilitating evolution. But, gene flow could in fact constrain rather than facilitate local adaptive evolution if immigrants have low additive genetic values for local fitness. Local migration‐selection balance and micro‐evolutionary stasis could then result. However, key quantitative genetic effects of natural immigration, comprising the degrees to which gene flow increases the total local additive genetic variance yet counteracts local adaptive evolutionary change, have not been explicitly quantified in wild populations. Key implications of gene flow for population and evolutionary dynamics consequently remain unclear. Our quantitative genetic analyses of long‐term data from free‐living song sparrows (Melospiza melodia) show that mean breeding value for local juvenile survival to adulthood, a major component of fitness, increased across cohorts more than expected solely due to drift. Such micro‐evolutionary change should be expected given nonzero additive genetic variance and consistent directional selection. However, this evolutionary increase was counteracted by negative additive genetic effects of recent immigrants, which increased total additive genetic variance but prevented a net directional evolutionary increase in total additive genetic value. These analyses imply an approximate quantitative genetic migration‐selection balance in a major fitness component, and hence demonstrate a key mechanism by which substantial additive genetic variation can be maintained yet decoupled from local adaptive evolutionary change.
Collapse
Affiliation(s)
- Jane M Reid
- Centre for Biodiversity Dynamics NTNU Trondheim Norway.,School of Biological Sciences University of Aberdeen Aberdeen UK
| | - Peter Arcese
- Forest & Conservation Sciences University of British Columbia Vancouver British Columbia Canada
| | - Pirmin Nietlisbach
- School of Biological Sciences Illinois State University Normal Illinois USA
| | - Matthew E Wolak
- Department of Biological Sciences Auburn University Auburn Alaska USA
| | - Stefanie Muff
- Centre for Biodiversity Dynamics NTNU Trondheim Norway.,Department of Mathematical Sciences NTNU Trondheim Norway
| | - Lisa Dickel
- Centre for Biodiversity Dynamics NTNU Trondheim Norway
| | - Lukas F Keller
- Department of Evolutionary Biology & Environmental Studies University of Zurich Zurich Switzerland.,Zoological Museum University of Zurich Zurich Switzerland
| |
Collapse
|
8
|
Maciejewski MF, Jiang C, Stuart YE, Bolnick DI. Microhabitat contributes to microgeographic divergence in threespine stickleback. Evolution 2020; 74:749-763. [PMID: 32058582 DOI: 10.1111/evo.13942] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 01/22/2020] [Accepted: 01/27/2020] [Indexed: 12/20/2022]
Abstract
Since the New Synthesis, most migration-selection balance theory has predicted that there should be negligible differentiation over small spatial scales (relative to dispersal), because gene flow should erode any effect of divergent selection. Nevertheless, there are classic examples of microgeographic divergence, which theory suggests can arise under specific conditions: exceptionally strong selection, phenotypic plasticity in philopatric individuals, or nonrandom dispersal. Here, we present evidence of microgeographic morphological variation within lake and stream populations of threespine stickleback (Gasterosteus aculeatus). It seems reasonable to assume that a given lake or stream population of fish is well-mixed. However, we found this assumption to be untenable. We examined trap-to-trap variation in 34 morphological traits measured on stickleback from 16 lakes and 16 streams. Most traits varied appreciably among traps within populations. Both between-trap distance and microhabitat characteristics such as depth and substrate explained some of the within-population morphological variance. Microhabitat was also associated with genotype at particular loci but there was no genetic isolation by distance, implying that heritable habitat preferences may contribute to microgeographic variation. Our study adds to growing evidence that microgeographic divergence can occur across small spatial scales within individuals' daily dispersal neighborhood where gene flow is expected to be strong.
Collapse
Affiliation(s)
- Meghan F Maciejewski
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, Connecticut, 06269
| | - Cynthia Jiang
- Department of Integrative Biology, University of Texas at Austin, Austin, Texas, 78705.,Long School of Medicine, UT Health Science Center San Antonio, San Antonio, Texas, 78229
| | - Yoel E Stuart
- Department of Integrative Biology, University of Texas at Austin, Austin, Texas, 78705.,Loyola University Chicago, Chicago, Illinois, 60660
| | - Daniel I Bolnick
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, Connecticut, 06269.,Department of Integrative Biology, University of Texas at Austin, Austin, Texas, 78705
| |
Collapse
|
9
|
Sasaki MC, Dam HG. Integrating patterns of thermal tolerance and phenotypic plasticity with population genetics to improve understanding of vulnerability to warming in a widespread copepod. GLOBAL CHANGE BIOLOGY 2019; 25:4147-4164. [PMID: 31449341 DOI: 10.1111/gcb.14811] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 08/12/2019] [Accepted: 08/20/2019] [Indexed: 06/10/2023]
Abstract
Differences in population vulnerability to warming are defined by spatial patterns in thermal adaptation. These patterns may be driven by natural selection over spatial environmental gradients, but can also be shaped by gene flow, especially in marine taxa with high dispersal potential. Understanding and predicting organismal responses to warming requires disentangling the opposing effects of selection and gene flow. We begin by documenting genetic divergence of thermal tolerance and developmental phenotypic plasticity. Ten populations of the widespread copepod Acartia tonsa were collected from sites across a large thermal gradient, ranging from the Florida Keys to Northern New Brunswick, Canada (spanning over 20° latitude). Thermal performance curves (TPCs) from common garden experiments revealed local adaptation at the sampling range extremes, with thermal tolerance increasing at low latitudes and decreasing at high latitudes. The opposite pattern was observed in phenotypic plasticity, which was strongest at high latitudes. No relationship was observed between phenotypic plasticity and environmental variables. Instead, the results are consistent with the hypothesis of a trade-off between thermal tolerance and the strength of phenotypic plasticity. Over a large portion of the sampled range, however, we observed a remarkable lack of differentiation of TPCs. To examine whether this lack of divergence is the result of selection for a generalist performance curve or constraint by gene flow, we analyzed cytochrome oxidase I mtDNA sequences, which revealed four distinct genetic clades, abundant genetic diversity, and widely distributed haplotypes. Strong divergence in thermal performance within genetic clades, however, suggests that the pace of thermal adaptation can be relatively rapid. The combined insight from the laboratory physiological experiments and genetic data indicate that gene flow constrains differentiation of TPCs. This balance between gene flow and selection has implications for patterns of vulnerability to warming. Taking both genetic differentiation and phenotypic plasticity into account, our results suggest that local adaptation does not increase vulnerability to warming, and that low-latitude populations in general may be more vulnerable to predicted temperature change over the next century.
Collapse
Affiliation(s)
- Matthew C Sasaki
- Department of Marine Sciences, University of Connecticut, Groton, CT, USA
| | - Hans G Dam
- Department of Marine Sciences, University of Connecticut, Groton, CT, USA
| |
Collapse
|
10
|
Brady SP, Bolnick DI, Barrett RDH, Chapman L, Crispo E, Derry AM, Eckert CG, Fraser DJ, Fussmann GF, Gonzalez A, Guichard F, Lamy T, Lane J, McAdam AG, Newman AEM, Paccard A, Robertson B, Rolshausen G, Schulte PM, Simons AM, Vellend M, Hendry A. Understanding Maladaptation by Uniting Ecological and Evolutionary Perspectives. Am Nat 2019; 194:495-515. [PMID: 31490718 DOI: 10.1086/705020] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Evolutionary biologists have long trained their sights on adaptation, focusing on the power of natural selection to produce relative fitness advantages while often ignoring changes in absolute fitness. Ecologists generally have taken a different tack, focusing on changes in abundance and ranges that reflect absolute fitness while often ignoring relative fitness. Uniting these perspectives, we articulate various causes of relative and absolute maladaptation and review numerous examples of their occurrence. This review indicates that maladaptation is reasonably common from both perspectives, yet often in contrasting ways. That is, maladaptation can appear strong from a relative fitness perspective, yet populations can be growing in abundance. Conversely, resident individuals can appear locally adapted (relative to nonresident individuals) yet be declining in abundance. Understanding and interpreting these disconnects between relative and absolute maladaptation, as well as the cases of agreement, is increasingly critical in the face of accelerating human-mediated environmental change. We therefore present a framework for studying maladaptation, focusing in particular on the relationship between absolute and relative fitness, thereby drawing together evolutionary and ecological perspectives. The unification of these ecological and evolutionary perspectives has the potential to bring together previously disjunct research areas while addressing key conceptual issues and specific practical problems.
Collapse
|
11
|
Bolnick DI, Barrett RD, Oke KB, Rennison DJ, Stuart YE. (Non)Parallel Evolution. ANNUAL REVIEW OF ECOLOGY EVOLUTION AND SYSTEMATICS 2018. [DOI: 10.1146/annurev-ecolsys-110617-062240] [Citation(s) in RCA: 155] [Impact Index Per Article: 25.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Parallel evolution across replicate populations has provided evolutionary biologists with iconic examples of adaptation. When multiple populations colonize seemingly similar habitats, they may evolve similar genes, traits, or functions. Yet, replicated evolution in nature or in the laboratory often yields inconsistent outcomes: Some replicate populations evolve along highly similar trajectories, whereas other replicate populations evolve to different extents or in distinct directions. To understand these heterogeneous outcomes, biologists are increasingly treating parallel evolution not as a binary phenomenon but rather as a quantitative continuum ranging from parallel to nonparallel. By measuring replicate populations’ positions along this (non)parallel continuum, we can test hypotheses about evolutionary and ecological factors that influence the extent of repeatable evolution. We review evidence regarding the manifestation of (non)parallel evolution in the laboratory, in natural populations, and in applied contexts such as cancer. We enumerate the many genetic, ecological, and evolutionary processes that contribute to variation in the extent of parallel evolution.
Collapse
Affiliation(s)
- Daniel I. Bolnick
- Department of Integrative Biology, University of Texas at Austin, Austin, Texas 78712, USA
- Current affiliation: Department of Ecology and Evolution, University of Connecticut, Storrs, Connecticut 06268, USA
| | | | - Krista B. Oke
- Redpath Museum, McGill University, Montreal, Quebec H3A 2K6, Canada
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, California 95060, USA
| | - Diana J. Rennison
- Institute of Ecology and Evolution, University of Bern, 3012 Bern, Switzerland
| | - Yoel E. Stuart
- Department of Integrative Biology, University of Texas at Austin, Austin, Texas 78712, USA
| |
Collapse
|
12
|
McDonald TK, Yeaman S. Effect of migration and environmental heterogeneity on the maintenance of quantitative genetic variation: a simulation study. J Evol Biol 2018; 31:1386-1399. [PMID: 29938863 DOI: 10.1111/jeb.13341] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Revised: 06/15/2018] [Accepted: 06/19/2018] [Indexed: 01/15/2023]
Abstract
The paradox of high genetic variation observed in traits under stabilizing selection is a long-standing problem in evolutionary theory, as mutation rates appear too low to explain observed levels of standing genetic variation under classic models of mutation-selection balance. Spatially or temporally heterogeneous environments can maintain more standing genetic variation within populations than homogeneous environments, but it is unclear whether such conditions can resolve the above discrepancy between theory and observation. Here, we use individual-based simulations to explore the effect of various types of environmental heterogeneity on the maintenance of genetic variation (VA ) for a quantitative trait under stabilizing selection. We find that VA is maximized at intermediate migration rates in spatially heterogeneous environments and that the observed patterns are robust to changes in population size. Spatial environmental heterogeneity increased variation by as much as 10-fold over mutation-selection balance alone, whereas pure temporal environmental heterogeneity increased variance by only 45% at max. Our results show that some combinations of spatial heterogeneity and migration can maintain considerably more variation than mutation-selection balance, potentially reconciling the discrepancy between theoretical predictions and empirical observations. However, given the narrow regions of parameter space required for this effect, this is unlikely to provide a general explanation for the maintenance of variation. Nonetheless, our results suggest that habitat fragmentation may affect the maintenance of VA and thereby reduce the adaptive capacity of populations.
Collapse
Affiliation(s)
| | - Sam Yeaman
- Department of Biological Sciences, University of Calgary, Calgary, Canada
| |
Collapse
|
13
|
Barts N, Greenway R, Passow CN, Arias-Rodriguez L, Kelley JL, Tobler M. Molecular evolution and expression of oxygen transport genes in livebearing fishes (Poeciliidae) from hydrogen sulfide rich springs. Genome 2018; 61:273-286. [DOI: 10.1139/gen-2017-0051] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Hydrogen sulfide (H2S) is a natural toxicant in some aquatic environments that has diverse molecular targets. It binds to oxygen transport proteins, rendering them non-functional by reducing oxygen-binding affinity. Hence, organisms permanently inhabiting H2S-rich environments are predicted to exhibit adaptive modifications to compensate for the reduced capacity to transport oxygen. We investigated 10 lineages of fish of the family Poeciliidae that have colonized freshwater springs rich in H2S—along with related lineages from non-sulfidic environments—to test hypotheses about the expression and evolution of oxygen transport genes in a phylogenetic context. We predicted shifts in the expression of and signatures of positive selection on oxygen transport genes upon colonization of H2S-rich habitats. Our analyses indicated significant shifts in gene expression for multiple hemoglobin genes in lineages that have colonized H2S-rich environments, and three hemoglobin genes exhibited relaxed selection in sulfidic compared to non-sulfidic lineages. However, neither changes in gene expression nor signatures of selection were consistent among all lineages in H2S-rich environments. Oxygen transport genes may consequently be predictable targets of selection during adaptation to sulfidic environments, but changes in gene expression and molecular evolution of oxygen transport genes in H2S-rich environments are not necessarily repeatable across replicated lineages.
Collapse
Affiliation(s)
- Nicholas Barts
- Division of Biology, Kansas State University, 116 Ackert Hall, Manhattan, KS 66506, USA
| | - Ryan Greenway
- Division of Biology, Kansas State University, 116 Ackert Hall, Manhattan, KS 66506, USA
| | - Courtney N. Passow
- Ecology, Evolution and Behavior, University of Minnesota St. Paul, 205 Cargill Building, St. Paul, MN 55108, USA
| | - Lenin Arias-Rodriguez
- División Académica de Ciencias Biológicas, Universidad Juárez Autónoma de Tabasco (UJAT), C.P. 86150, Villahermosa, Tabasco, México
| | - Joanna L. Kelley
- Department of Biological Sciences, Washington State University, 431 Heald Hall, Pullman, WA 99164, USA
| | - Michael Tobler
- Division of Biology, Kansas State University, 116 Ackert Hall, Manhattan, KS 66506, USA
| |
Collapse
|
14
|
Walter RP, Roy D, Hussey NE, Stelbrink B, Kovacs KM, Lydersen C, McMeans BC, Svavarsson J, Kessel ST, Biton Porsmoguer S, Wildes S, Tribuzio CA, Campana SE, Petersen SD, Grubbs RD, Heath DD, Hedges KJ, Fisk AT. Origins of the Greenland shark ( Somniosus microcephalus): Impacts of ice-olation and introgression. Ecol Evol 2017; 7:8113-8125. [PMID: 29043060 PMCID: PMC5632604 DOI: 10.1002/ece3.3325] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Revised: 06/07/2017] [Accepted: 07/21/2017] [Indexed: 12/04/2022] Open
Abstract
Herein, we use genetic data from 277 sleeper sharks to perform coalescent‐based modeling to test the hypothesis of early Quaternary emergence of the Greenland shark (Somniosus microcephalus) from ancestral sleeper sharks in the Canadian Arctic‐Subarctic region. Our results show that morphologically cryptic somniosids S. microcephalus and Somniosus pacificus can be genetically distinguished using combined mitochondrial and nuclear DNA markers. Our data confirm the presence of genetically admixed individuals in the Canadian Arctic and sub‐Arctic, and temperate Eastern Atlantic regions, suggesting introgressive hybridization upon secondary contact following the initial species divergence. Conservative substitution rates fitted to an Isolation with Migration (IM) model indicate a likely species divergence time of 2.34 Ma, using the mitochondrial sequence DNA, which in conjunction with the geographic distribution of admixtures and Pacific signatures likely indicates speciation associated with processes other than the closing of the Isthmus of Panama. This time span coincides with further planetary cooling in the early Quaternary period followed by the onset of oscillating glacial‐interglacial cycles. We propose that the initial S. microcephalus–S. pacificus split, and subsequent hybridization events, were likely associated with the onset of Pleistocene glacial oscillations, whereby fluctuating sea levels constrained connectivity among Arctic oceanic basins, Arctic marginal seas, and the North Atlantic Ocean. Our data demonstrates support for the evolutionary consequences of oscillatory vicariance via transient oceanic isolation with subsequent secondary contact associated with fluctuating sea levels throughout the Quaternary period—which may serve as a model for the origins of Arctic marine fauna on a broad taxonomic scale.
Collapse
Affiliation(s)
- Ryan P Walter
- Department of Biological Science California State University Fullerton CA USA.,Great Lakes Institute for Environmental Research University of Windsor Windsor ON Canada
| | - Denis Roy
- Department of Natural Resources and the Environment Wildlife and Fisheries Conservation Center and Center for Environmental Sciences and Engineering University of Connecticut Storrs CT USA
| | - Nigel E Hussey
- Biological Sciences University of Windsor Windsor ON Canada
| | | | - Kit M Kovacs
- Fram Centre Norwegian Polar Institute Tromsø Norway
| | | | - Bailey C McMeans
- Great Lakes Institute for Environmental Research University of Windsor Windsor ON Canada.,Department of Biology University of Toronto Mississauga Mississauga ON Canada
| | - Jörundur Svavarsson
- Faculty of Life and Environmental Sciences University of Iceland Reykjavík Iceland
| | - Steven T Kessel
- Department of Fisheries and Wildlife Michigan State University East Lansing MI USA
| | - Sebastián Biton Porsmoguer
- Mediterranean Institute of Oceanography (MIO) UM 110 Aix-Marseille University CNRS/INSU Toulon University IRD Marseille France
| | - Sharon Wildes
- Auke Bay Laboratories AFSC/NMFS/NOAA/DOC Ted Stevens Marine Research Institute Juneau AK USA
| | - Cindy A Tribuzio
- Auke Bay Laboratories AFSC/NMFS/NOAA/DOC Ted Stevens Marine Research Institute Juneau AK USA
| | - Steven E Campana
- Faculty of Life and Environmental Sciences University of Iceland Reykjavík Iceland
| | - Stephen D Petersen
- Conservation and Research Department Assiniboine Park Zoo Winnipeg MB Canada
| | - R Dean Grubbs
- Coastal and Marine Laboratory Florida State University St. Teresa FL USA
| | - Daniel D Heath
- Great Lakes Institute for Environmental Research University of Windsor Windsor ON Canada
| | - Kevin J Hedges
- Arctic Aquatic Research Division Fisheries and Oceans Canada Winnipeg MB Canada
| | - Aaron T Fisk
- Great Lakes Institute for Environmental Research University of Windsor Windsor ON Canada
| |
Collapse
|
15
|
Inderjit, Catford JA, Kalisz S, Simberloff D, Wardle DA. A framework for understanding human‐driven vegetation change. OIKOS 2017. [DOI: 10.1111/oik.04587] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Inderjit
- Dept of Environmental Studies Centre for Environmental Management of Degraded Ecosystems (CEMDE), Univ. of Delhi Delhi India
| | - Jane A. Catford
- Biological Sciences Univ. of Southampton, Southampton, UK, and: School of BioSciences, The Univ. of Melbourne Victoria Australia
| | - Susan Kalisz
- Dept of Ecology and Evolutionary Biology Univ. of Tennessee Knoxville TN USA
| | - Daniel Simberloff
- Dept of Ecology and Evolutionary Biology Univ. of Tennessee Knoxville TN USA
| | - David A. Wardle
- Dept of Forest Ecology and Management Swedish Univ. of Agricultural Sciences Umeå Sweden
- Asian School of the Environment, Nanyang Technological Univ. Singapore
| |
Collapse
|
16
|
Feng X, He D, Sui X, Chen Y, Chen Y. Morphological and genetic divergence between lake and river populations of Triplophysa in Ngangtse Co, Tibet. Mitochondrial DNA A DNA Mapp Seq Anal 2017; 29:778-784. [PMID: 28756717 DOI: 10.1080/24701394.2017.1357711] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Ngangtse Co (4535 m a.s.l., 840 km2) is a typical endorheic lake in Tibet. In 2015, we investigated the fish resource in this lake and its rivers and collected two Triplophysa species, including T. brevicauda and T. stewarti. To understand the evolutionary dynamics of Triplophysa in Ngangtse Co, the adaptive and genetic divergence between river and lake populations were investigated by analysing their morphological characteristics and mitochondrial COI and Cytb sequences. Among all of 277 samples, the ratios of the number of T. brevicauda to T. stewarti were 27:8, 34:11, 14:24, 37:0, 16:23 and 0:83 in river populations RA, RB, RC, RD, lakeside population LSE and lake population L, respectively. For T. brevicauda, a small but significant genetic divergence (mean FST = 0.0890) was detected between population RD and other three river populations, and significant morphological differences of body length/body height and body length/caudal peduncle length were observed between population RD and RA, RB, suggesting an association between differentiation and geographical distance. For T. stewarti, very high levels of genetic differentiation was observed between population L and other populations with the FST values ranging from 0.4737 (L-RA) to 0.7074 (L-RC). In addition, significant differences of most of morphological characteristics were observed between the lake (L) and river (RC) populations, indicating that lake fish of T. stewarti was a population that showed a long-term adaptation to the saltwater lake. These results provide insights on the evolutionary dynamics of Triplophysa in Ngangtse Co and help us to understand the fish speciation in endorheic lakes on the Qinghai-Tibetan Plateau.
Collapse
Affiliation(s)
- Xiu Feng
- a The Key Laboratory of Aquatic Biodiversity and Conservation , Institute of Hydrobiology, Chinese Academy of Sciences , Wuhan , China
| | - Dekui He
- a The Key Laboratory of Aquatic Biodiversity and Conservation , Institute of Hydrobiology, Chinese Academy of Sciences , Wuhan , China
| | - Xiaoyun Sui
- a The Key Laboratory of Aquatic Biodiversity and Conservation , Institute of Hydrobiology, Chinese Academy of Sciences , Wuhan , China
| | - Yongxia Chen
- b College of Life Sciences , Hebei University , Baoding , China
| | - Yifeng Chen
- a The Key Laboratory of Aquatic Biodiversity and Conservation , Institute of Hydrobiology, Chinese Academy of Sciences , Wuhan , China
| |
Collapse
|
17
|
Pedersen SH, Ferchaud AL, Bertelsen MS, Bekkevold D, Hansen MM. Low genetic and phenotypic divergence in a contact zone between freshwater and marine sticklebacks: gene flow constrains adaptation. BMC Evol Biol 2017; 17:130. [PMID: 28587593 PMCID: PMC5461706 DOI: 10.1186/s12862-017-0982-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Accepted: 05/26/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Distinct hybrid zones and phenotypic and genomic divergence is often observed between marine and freshwater threespine sticklebacks (Gasterosteus aculeatus). Nevertheless, cases also exist where marine-freshwater divergence is diffuse despite seemingly similar environmental settings. In order to assess what characterizes these highly different outcomes, we focused on the latter kind of system in the Odder River, Denmark. Here, a previous study based on RAD (Restriction site Associated DNA) sequencing found non-significant genome-wide differentiation between marine and freshwater sticklebacks. In the present study, we analyzed samples on a finer geographical scale. We assessed if the system should be regarded as panmictic, or if fine-scale genetic structure and local selection was present but dominated by strong migration. We also asked if specific population components, that is the two sexes and different lateral plate morphs, contributed disproportionally more to dispersal. RESULTS We assessed variation at 96 SNPs and the Eda gene that affects lateral plate number, conducted molecular sex identification, and analyzed morphological traits. Genetic differentiation estimated by FST was non-significant throughout the system. Nevertheless, spatial autocorrelation analysis suggested fine scale genetic structure with a genetic patch size of 770 m. There was no evidence for sex-biased dispersal, but full-plated individuals showed higher dispersal than low- and partial-plated individuals. The system was dominated by full-plated morphs characteristic of marine sticklebacks, but in the upstream part of the river body shape and frequency of low-plated morphs changed in the direction expected for freshwater sticklebacks. Five markers including Eda were under possible diversifying selection. However, only subtle clinal patterns were observed for traits and markers. CONCLUSIONS We suggest that gene flow from marine sticklebacks overwhelms adaptation to freshwater conditions, but the short genetic patch size means that the effect of gene flow on the most upstream region must be indirect and occurs over generations. The occurrence of both weak unimodal and strong bimodal hybrid zones within the same species is striking. We suggest environmental and demographic factors that could determine these outcomes, but also highlight the possibility that long-term population history and the presence or absence of genomic incompatibilities could be a contributing factor.
Collapse
Affiliation(s)
- Susanne Holst Pedersen
- Department of Bioscience, Aarhus University, Ny Munkegade 114, DK-8000, Aarhus C, Denmark
| | - Anne-Laure Ferchaud
- Department of Bioscience, Aarhus University, Ny Munkegade 114, DK-8000, Aarhus C, Denmark.,Present address: Département de Biologie, Institut de Biologie Intégrative et des Systèmes (IBIS), Pavillon Charles-Eugène-Marchand, Université Laval, Québec City, QC, Canada
| | - Mia S Bertelsen
- Department of Bioscience, Aarhus University, Ny Munkegade 114, DK-8000, Aarhus C, Denmark
| | - Dorte Bekkevold
- National Institute of Aquatic Resources, Technical University of Denmark, Vejlsøvej 39, 8600, Silkeborg, Denmark
| | - Michael M Hansen
- Department of Bioscience, Aarhus University, Ny Munkegade 114, DK-8000, Aarhus C, Denmark.
| |
Collapse
|
18
|
Abstract
Evolutionary biologists typically represent clines as spatial gradients in a univariate character (or a principal-component axis) whose mean changes as a function of location along a transect spanning an environmental gradient or ecotone. This univariate approach may obscure the multivariate nature of phenotypic evolution across a landscape. Clines might instead be plotted as a series of vectors in multidimensional morphospace, connecting sequential geographic sites. We present a model showing that clines may trace nonlinear paths that arc through morphospace rather than elongating along a single major trajectory. Arcing clines arise because different characters diverge at different rates or locations along a geographic transect. We empirically confirm that some clines arc through morphospace, using morphological data from threespine stickleback sampled along eight independent transects from lakes down their respective outlet streams. In all eight clines, successive vectors of lake-stream divergence fluctuate in direction and magnitude in trait space, rather than pointing along a single phenotypic axis. Most clines exhibit surprisingly irregular directions of divergence as one moves downstream, although a few clines exhibit more directional arcs through morphospace. Our results highlight the multivariate complexity of clines that cannot be captured with the traditional graphical framework. We discuss hypotheses regarding the causes, and implications, of such arcing multivariate clines.
Collapse
|
19
|
Jiang Y, Peichel CL, Torrance L, Rizvi Z, Thompson S, Palivela VV, Pham H, Ling F, Bolnick DI. Sensory trait variation contributes to biased dispersal of threespine stickleback in flowing water. J Evol Biol 2017; 30:681-695. [PMID: 28029723 DOI: 10.1111/jeb.13035] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Revised: 12/16/2016] [Accepted: 12/20/2016] [Indexed: 12/13/2022]
Abstract
Gene flow is widely thought to homogenize spatially separate populations, eroding effects of divergent selection. The resulting theory of 'migration-selection balance' is predicated on a common assumption that all genotypes are equally prone to dispersal. If instead certain genotypes are disproportionately likely to disperse, then migration can actually promote population divergence. For example, previous work has shown that threespine stickleback (Gasterosteus aculeatus) differ in their propensity to move up- or downstream ('rheotactic response'), which may facilitate genetic divergence between adjoining lake and stream populations of stickleback. Here, we demonstrate that intraspecific variation in a sensory system (superficial neuromast lines) contributes to this variation in swimming behaviour in stickleback. First, we show that intact neuromasts are necessary for a typical rheotactic response. Next, we showed that there is heritable variation in the number of neuromasts and that stickleback with more neuromasts are more likely to move downstream. Variation in pectoral fin shape contributes to additional variation in rheotactic response. These results illustrate how within-population quantitative variation in sensory and locomotor traits can influence dispersal behaviour, thereby biasing dispersal between habitats and favouring population divergence.
Collapse
Affiliation(s)
- Y Jiang
- Department of Integrative Biology, University of Texas at Austin, Austin, TX, USA
| | - C L Peichel
- Divisions of Basic Sciences and Human Biology, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - L Torrance
- Texas A&M University, Corpus Christi, TX, USA
| | - Z Rizvi
- Department of Integrative Biology, University of Texas at Austin, Austin, TX, USA
| | - S Thompson
- Department of Integrative Biology, University of Texas at Austin, Austin, TX, USA
| | - V V Palivela
- Department of Integrative Biology, University of Texas at Austin, Austin, TX, USA
| | - H Pham
- University of Texas Health Science Center, Houston, TX, USA
| | - F Ling
- Department of Fisheries Science, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, China
| | - D I Bolnick
- Department of Integrative Biology, University of Texas at Austin, Austin, TX, USA
| |
Collapse
|
20
|
Weber JN, Bradburd GS, Stuart YE, Stutz WE, Bolnick DI. Partitioning the effects of isolation by distance, environment, and physical barriers on genomic divergence between parapatric threespine stickleback. Evolution 2016; 71:342-356. [DOI: 10.1111/evo.13110] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Accepted: 10/15/2016] [Indexed: 01/09/2023]
Affiliation(s)
- Jesse N. Weber
- Department of Integrative Biology University of Texas at Austin Austin Texas 78712
- Division of Biological Sciences University of Montana Missoula Montana 59801
| | - Gideon S. Bradburd
- Department of Integrative Biology Michigan State University East Lansing Michigan 48824
| | - Yoel E. Stuart
- Department of Integrative Biology University of Texas at Austin Austin Texas 78712
| | - William E. Stutz
- Department of Integrative Biology University of Texas at Austin Austin Texas 78712
- Department of Ecology and Evolutionary Biology University of Colorado at Boulder Boulder Colorado 80309
| | - Daniel I. Bolnick
- Department of Integrative Biology University of Texas at Austin Austin Texas 78712
| |
Collapse
|
21
|
Hanson D, Moore JS, Taylor EB, Barrett RDH, Hendry AP. Assessing reproductive isolation using a contact zone between parapatric lake-stream stickleback ecotypes. J Evol Biol 2016; 29:2491-2501. [PMID: 27633750 DOI: 10.1111/jeb.12978] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2016] [Accepted: 09/02/2016] [Indexed: 01/09/2023]
Abstract
Ecological speciation occurs when populations evolve reproductive isolation as a result of divergent natural selection. This isolation can be influenced by many potential reproductive barriers, including selection against hybrids, selection against migrants and assortative mating. How and when these barriers act and interact in nature is understood for relatively few empirical systems. We used a mark-recapture experiment in a contact zone between lake and stream three-spined sticklebacks (Gasterosteus aculeatus, Linnaeus) to evaluate the occurrence of hybrids (allowing inferences about mating isolation), the interannual survival of hybrids (allowing inferences about selection against hybrids) and the shift in lake-like vs. stream-like characteristics (allowing inferences about selection against migrants). Genetic and morphological data suggest the occurrence of hybrids and no selection against hybrids in general, a result contradictory to a number of other studies of sticklebacks. However, we did find selection against more lake-like individuals, suggesting a barrier to gene flow from the lake into the stream. Combined with previous work on this system, our results suggest that multiple (most weakly and often asymmetric) barriers must be combining to yield substantial restrictions on gene flow. This work provides evidence of a reproductive barrier in lake-stream sticklebacks and highlights the value of assessing multiple reproductive barriers in natural contexts.
Collapse
Affiliation(s)
- D Hanson
- Redpath Museum and Department of Biology, McGill University, Montreal, QC, Canada
| | - J-S Moore
- Institut de Biologie Intégrative et des Systèmes, Université Laval, Québec, QC, Canada
| | - E B Taylor
- Department of Zoology and Beaty Biodiversity Museum, University of British Columbia, Vancouver, BC, Canada
| | - R D H Barrett
- Redpath Museum and Department of Biology, McGill University, Montreal, QC, Canada
| | - A P Hendry
- Redpath Museum and Department of Biology, McGill University, Montreal, QC, Canada
| |
Collapse
|
22
|
Takahashi Y, Suyama Y, Matsuki Y, Funayama R, Nakayama K, Kawata M. Lack of genetic variation prevents adaptation at the geographic range margin in a damselfly. Mol Ecol 2016; 25:4450-60. [PMID: 27501054 DOI: 10.1111/mec.13782] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Revised: 07/21/2016] [Accepted: 07/22/2016] [Indexed: 01/21/2023]
Abstract
What limits a species' distribution in the absence of physical barriers? Genetic load due to asymmetric gene flow and the absence of genetic variation due to lack of gene flow are hypothesized to constrain adaptation to novel environments in marginal populations, preventing range expansion. Here, we examined the genetic structure and geographic variation in morphological traits in two damselflies (Ischnura asiatica and I. senegalensis) along a latitudinal gradient in Japan, which is the distribution centre of I. asiatica and the northern limit of I. senegalensis. Genomewide genetic analyses found a loss of genetic diversity at the edge of distribution in I. senegalensis but consistently high diversity in I. asiatica. Gene flow was asymmetric in a south-north direction in both species. Although body size and wing loading showed decreasing latitudinal clines (smaller in north) in I. asiatica in Japan, increasing latitudinal clines (larger in north) in these phenotypic markers were observed in I. senegalensis, particularly near the northern boundary, which coincided well with the location where genetic diversity began a sharp decline. In ectothermic animals, increasing latitudinal cline in these traits was suggested to be established when they failed to adapt to thermal gradient. Therefore, our findings support the possibility that a lack of genetic variation rather than geneflow swamping is responsible for the constraint of adaptation at the margin of geographic distribution.
Collapse
Affiliation(s)
- Yuma Takahashi
- Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, 6-3 Aoba, Aramaki, Aoba, Sendai, Miyagi, 980-8578, Japan. .,Division of Ecology and Evolutionary Biology, Graduate School of Life Sciences, Tohoku University, 6-3 Aoba, Aramaki, Aoba, Sendai, Miyagi, 980-8578, Japan.
| | - Yoshihisa Suyama
- Field Science Center, Graduate School of Agricultural Science, Tohoku University, 232-3 Yomogida, Naruko-onsen, Osaki, Miyagi, 989-6711, Japan
| | - Yu Matsuki
- Field Science Center, Graduate School of Agricultural Science, Tohoku University, 232-3 Yomogida, Naruko-onsen, Osaki, Miyagi, 989-6711, Japan
| | - Ryo Funayama
- Department of Cell Proliferation, United Center for Advanced Research and Translational Medicine, Graduate School of Medicine, Tohoku University, 2-1 Seiryo, Aoba, Sendai, 980-8575, Japan
| | - Keiko Nakayama
- Department of Cell Proliferation, United Center for Advanced Research and Translational Medicine, Graduate School of Medicine, Tohoku University, 2-1 Seiryo, Aoba, Sendai, 980-8575, Japan
| | - Masakado Kawata
- Division of Ecology and Evolutionary Biology, Graduate School of Life Sciences, Tohoku University, 6-3 Aoba, Aramaki, Aoba, Sendai, Miyagi, 980-8578, Japan
| |
Collapse
|
23
|
Comeault AA, Matute DR. Reinforcement's incidental effects on reproductive isolation between conspecifics. Curr Zool 2016; 62:135-143. [PMID: 29491901 PMCID: PMC5804225 DOI: 10.1093/cz/zow002] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Accepted: 01/11/2016] [Indexed: 12/26/2022] Open
Abstract
Reinforcement—the process whereby maladaptive hybridization leads to the strengthening of prezygotic isolation between species—has a long history in the study of speciation. Because reinforcement affects traits involved in mate choice and fertility, it can have indirect effects on reproductive isolation between populations within species. Here we review examples of these “cascading effects of reinforcement” (CER) and discuss different mechanisms through which they can arise. We discuss three factors that are predicted to influence the potential occurrence of CER: rates of gene flow among populations, the strength of selection acting on the traits involved in reinforcement, and the genetic basis of those traits. We suggest that CER is likely if (1) the rate of gene flow between conspecific populations is low; (2) divergent selection acts on phenotypes involved in reinforcement between sympatric and allopatric populations; and (3) the genetic response to reinforcement differs among conspecific populations subject to parallel reinforcing selection. Future work continuing to address gene flow, selection, and the genetic basis of the traits involved in the reinforcement will help develop a better understanding of reinforcement as a process driving the production of species diversity, both directly and incidentally.
Collapse
Affiliation(s)
- Aaron A Comeault
- Biology Department, University of North Carolina, 250 Bell Tower Road, Chapel Hill, NC 27599, USA
| | - Daniel R Matute
- Biology Department, University of North Carolina, 250 Bell Tower Road, Chapel Hill, NC 27599, USA
| |
Collapse
|
24
|
Ferchaud AL, Hansen MM. The impact of selection, gene flow and demographic history on heterogeneous genomic divergence: three-spine sticklebacks in divergent environments. Mol Ecol 2015; 25:238-59. [DOI: 10.1111/mec.13399] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Revised: 09/15/2015] [Accepted: 09/21/2015] [Indexed: 01/14/2023]
Affiliation(s)
- Anne-Laure Ferchaud
- Department of Bioscience; Aarhus University; Ny Munkegade 114-116 DK-8000 Aarhus C Denmark
| | - Michael M. Hansen
- Department of Bioscience; Aarhus University; Ny Munkegade 114-116 DK-8000 Aarhus C Denmark
| |
Collapse
|
25
|
Oke KB, Bukhari M, Kaeuffer R, Rolshausen G, Räsänen K, Bolnick DI, Peichel CL, Hendry AP. Does plasticity enhance or dampen phenotypic parallelism? A test with three lake–stream stickleback pairs. J Evol Biol 2015; 29:126-43. [DOI: 10.1111/jeb.12767] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Revised: 09/18/2015] [Accepted: 09/21/2015] [Indexed: 12/19/2022]
Affiliation(s)
- K. B. Oke
- Redpath Museum and Department of Biology McGill University Montreal QC Canada
| | - M. Bukhari
- Redpath Museum and Department of Biology McGill University Montreal QC Canada
| | - R. Kaeuffer
- Redpath Museum and Department of Biology McGill University Montreal QC Canada
| | - G. Rolshausen
- Redpath Museum and Department of Biology McGill University Montreal QC Canada
| | - K. Räsänen
- Department of Aquatic Ecology Eawag and Institute of Integrative Biology ETH‐Zurich Duebendorf Switzerland
| | - D. I. Bolnick
- Department of Integrative Biology University of Texas at Austin Austin TX USA
| | - C. L. Peichel
- Divisions of Basic Sciences and Human Biology Fred Hutchinson Cancer Research Center Seattle WA USA
| | - A. P. Hendry
- Redpath Museum and Department of Biology McGill University Montreal QC Canada
| |
Collapse
|
26
|
Rolshausen G, Phillip DAT, Beckles DM, Akbari A, Ghoshal S, Hamilton PB, Tyler CR, Scarlett AG, Ramnarine I, Bentzen P, Hendry AP. Do stressful conditions make adaptation difficult? Guppies in the oil-polluted environments of southern Trinidad. Evol Appl 2015; 8:854-70. [PMID: 26495039 PMCID: PMC4610383 DOI: 10.1111/eva.12289] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Accepted: 05/26/2015] [Indexed: 12/27/2022] Open
Abstract
The ability of populations to rapidly adapt to new environments will determine their future in an increasingly human-modified world. Although meta-analyses do frequently uncover signatures of local adaptation, they also reveal many exceptions. We suggest that particular constraints on local adaptation might arise when organisms are exposed to novel stressors, such as anthropogenic pollution. To inform this possibility, we studied the extent to which guppies (Poecilia reticulata) show local adaptation to oil pollution in southern Trinidad. Neutral genetic markers revealed that paired populations in oil-polluted versus not-polluted habitats diverged independently in two different watersheds. Morphometrics revealed some divergence (particularly in head shape) between these environments, some of which was parallel between rivers. Reciprocal transplant experiments in nature, however, found little evidence of local adaptation based on survival and growth. Moreover, subsequent laboratory experiments showed that the two populations from oil-polluted sites showed only weak local adaptation even when compared to guppies from oil-free northern Trinidad. We conclude that guppies show little local adaptation to oil pollution, which might result from the challenges associated with adaptation to particularly stressful environments. It might also reflect genetic drift owing to small population sizes and/or high gene flow between environments.
Collapse
Affiliation(s)
- Gregor Rolshausen
- Redpath Museum and Department of Biology, McGill University Montreal, QC, Canada
| | - Dawn A T Phillip
- Department of Life Sciences, The University of the West Indies St. Augustine, Trinidad and Tobago
| | - Denise M Beckles
- Department of Chemistry, The University of the West Indies St. Augustine, Trinidad and Tobago
| | - Ali Akbari
- Department of Civil Engineering and Applied Mechanics, McGill University Montreal, QC, Canada
| | - Subhasis Ghoshal
- Department of Civil Engineering and Applied Mechanics, McGill University Montreal, QC, Canada
| | | | | | - Alan G Scarlett
- Biochemistry Research Center, University of Plymouth Drake Circus, Plymouth, UK
| | - Indar Ramnarine
- Department of Life Sciences, The University of the West Indies St. Augustine, Trinidad and Tobago
| | - Paul Bentzen
- Department of Biology, Dalhousie University Halifax, NS, Canada
| | - Andrew P Hendry
- Redpath Museum and Department of Biology, McGill University Montreal, QC, Canada
| |
Collapse
|
27
|
Konijnendijk N, Shikano T, Daneels D, Volckaert FAM, Raeymaekers JAM. Signatures of selection in the three-spined stickleback along a small-scale brackish water - freshwater transition zone. Ecol Evol 2015; 5:4174-86. [PMID: 26445666 PMCID: PMC4588664 DOI: 10.1002/ece3.1671] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Revised: 07/13/2015] [Accepted: 07/22/2015] [Indexed: 01/31/2023] Open
Abstract
Local adaptation is often obvious when gene flow is impeded, such as observed at large spatial scales and across strong ecological contrasts. However, it becomes less certain at small scales such as between adjacent populations or across weak ecological contrasts, when gene flow is strong. While studies on genomic adaptation tend to focus on the former, less is known about the genomic targets of natural selection in the latter situation. In this study, we investigate genomic adaptation in populations of the three-spined stickleback Gasterosteus aculeatus L. across a small-scale ecological transition with salinities ranging from brackish to fresh. Adaptation to salinity has been repeatedly demonstrated in this species. A genome scan based on 87 microsatellite markers revealed only few signatures of selection, likely owing to the constraints that homogenizing gene flow puts on adaptive divergence. However, the detected loci appear repeatedly as targets of selection in similar studies of genomic adaptation in the three-spined stickleback. We conclude that the signature of genomic selection in the face of strong gene flow is weak, yet detectable. We argue that the range of studies of genomic divergence should be extended to include more systems characterized by limited geographical and ecological isolation, which is often a realistic setting in nature.
Collapse
Affiliation(s)
- Nellie Konijnendijk
- Laboratory of Biodiversity and Evolutionary Genomics University of Leuven Ch. Deberiotstraat 32, B-3000 Leuven Belgium
| | - Takahito Shikano
- Ecological Genetics Research Unit Department of Biosciences University of Helsinki P.O. Box 65 FI-000 14 Helsinki Finland
| | - Dorien Daneels
- Laboratory of Biodiversity and Evolutionary Genomics University of Leuven Ch. Deberiotstraat 32, B-3000 Leuven Belgium
| | - Filip A M Volckaert
- Laboratory of Biodiversity and Evolutionary Genomics University of Leuven Ch. Deberiotstraat 32, B-3000 Leuven Belgium
| | - Joost A M Raeymaekers
- Laboratory of Biodiversity and Evolutionary Genomics University of Leuven Ch. Deberiotstraat 32, B-3000 Leuven Belgium
| |
Collapse
|
28
|
Jiang Y, Torrance L, Peichel CL, Bolnick DI. Differences in rheotactic responses contribute to divergent habitat use between parapatric lake and stream threespine stickleback. Evolution 2015. [DOI: 10.1111/evo.12740] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Yuexin Jiang
- Department of Integrative Biology; University of Texas at Austin; One University Station C0990 Austin Texas 78712
- Department of Environmental Science and Policy; University of California at Davis; One Shields Avenue Davis California 95616
| | | | - Catherine L. Peichel
- Divisions of Human Biology and Basic Sciences; Fred Hutchinson Cancer Research Center; 1100 Fairview Ave. N. Seattle Washington 98109
| | - Daniel I. Bolnick
- Department of Integrative Biology; University of Texas at Austin; One University Station C0990 Austin Texas 78712
- Howard Hughes Medical Institute; University of Texas at Austin; One University Station C0990 Austin Texas 78712
| |
Collapse
|
29
|
Rolshausen G, Muttalib S, Kaeuffer R, Oke KB, Hanson D, Hendry AP. When maladaptive gene flow does not increase selection. Evolution 2015. [DOI: 10.1111/evo.12739] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Gregor Rolshausen
- Redpath Museum and Department of Biology; McGill University; 859 Sherbrooke St. W. Montreal Quebec H3A0C4 Canada
| | - Shahin Muttalib
- Redpath Museum and Department of Biology; McGill University; 859 Sherbrooke St. W. Montreal Quebec H3A0C4 Canada
| | - Renaud Kaeuffer
- Redpath Museum and Department of Biology; McGill University; 859 Sherbrooke St. W. Montreal Quebec H3A0C4 Canada
| | - Krista B. Oke
- Redpath Museum and Department of Biology; McGill University; 859 Sherbrooke St. W. Montreal Quebec H3A0C4 Canada
| | - Dieta Hanson
- Redpath Museum and Department of Biology; McGill University; 859 Sherbrooke St. W. Montreal Quebec H3A0C4 Canada
| | - Andrew P. Hendry
- Redpath Museum and Department of Biology; McGill University; 859 Sherbrooke St. W. Montreal Quebec H3A0C4 Canada
| |
Collapse
|
30
|
Débarre F, Yeaman S, Guillaume F. Evolution of Quantitative Traits under a Migration-Selection Balance: When Does Skew Matter? Am Nat 2015; 186 Suppl 1:S37-47. [PMID: 26656215 DOI: 10.1086/681717] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Quantitative-genetic models of differentiation under migration-selection balance often rely on the assumption of normally distributed genotypic and phenotypic values. When a population is subdivided into demes with selection toward different local optima, migration between demes may result in asymmetric, or skewed, local distributions. Using a simplified two-habitat model, we derive formulas without a priori assuming a Gaussian distribution of genotypic values, and we find expressions that naturally incorporate higher moments, such as skew. These formulas yield predictions of the expected divergence under migration-selection balance that are more accurate than models assuming Gaussian distributions, which illustrates the importance of incorporating these higher moments to assess the response to selection in heterogeneous environments. We further show with simulations that traits with loci of large effect display the largest skew in their distribution at migration-selection balance.
Collapse
Affiliation(s)
- Florence Débarre
- Department of Zoology and Biodiversity Research Centre, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada; and University of Exeter, Penryn Campus, Penryn, Cornwall, TR10 9FE, United Kingdom
| | | | | |
Collapse
|
31
|
Raeymaekers JAM, Maes GE, Geldof S, Hontis I, Nackaerts K, Volckaert FAM. Modeling genetic connectivity in sticklebacks as a guideline for river restoration. Evol Appl 2015; 1:475-88. [PMID: 25567729 PMCID: PMC3352376 DOI: 10.1111/j.1752-4571.2008.00019.x] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2007] [Accepted: 01/28/2008] [Indexed: 11/27/2022] Open
Abstract
Estimating genetic connectivity in disturbed riverine landscapes is of key importance for river restoration. However, few species of the disturbed riverine fauna may provide a detailed and basin-wide picture of the human impact on the population genetics of riverine organisms. Here we used the most abundant native fish, the three-spined stickleback (Gasterosteus aculeatus L.), to detect the geographical determinants of genetic connectivity in the eastern part of the Scheldt basin in Belgium. Anthropogenic structures came out as the strongest determinant of population structure, when evaluated against a geographically well-documented baseline model accounting for natural effects. These barriers not only affected genetic diversity, but they also controlled the balance between gene flow and genetic drift, and therefore may crucially disrupt the population structure of sticklebacks. Landscape models explained a high percentage of variation (allelic richness: adjusted R (2) = 0.78; pairwise F ST: adjusted R (2) = 0.60), and likely apply to other species as well. River restoration and conservation genetics may highly benefit from riverine landscape genetics, including model building, the detection of outlier populations, and a specific test for the geographical factors controlling the balance between gene flow and genetic drift.
Collapse
Affiliation(s)
- Joost A M Raeymaekers
- Laboratory for Animal Biodiversity and Systematics, Katholieke Universiteit Leuven Leuven, Belgium
| | - Gregory E Maes
- Laboratory for Animal Biodiversity and Systematics, Katholieke Universiteit Leuven Leuven, Belgium
| | - Sarah Geldof
- Laboratory for Animal Biodiversity and Systematics, Katholieke Universiteit Leuven Leuven, Belgium
| | - Ingrid Hontis
- Laboratory for Animal Biodiversity and Systematics, Katholieke Universiteit Leuven Leuven, Belgium
| | - Kris Nackaerts
- InterGraph Belgium NV, Tennessee House, Riverside Business Park Brussels, Belgium
| | - Filip A M Volckaert
- Laboratory for Animal Biodiversity and Systematics, Katholieke Universiteit Leuven Leuven, Belgium
| |
Collapse
|
32
|
Damasceno R, Strangas ML, Carnaval AC, Rodrigues MT, Moritz C. Revisiting the vanishing refuge model of diversification. Front Genet 2014; 5:353. [PMID: 25374581 PMCID: PMC4205810 DOI: 10.3389/fgene.2014.00353] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Accepted: 09/21/2014] [Indexed: 11/13/2022] Open
Abstract
Much of the debate around speciation and historical biogeography has focused on the role of stabilizing selection on the physiological (abiotic) niche, emphasizing how isolation and vicariance, when associated with niche conservatism, may drive tropical speciation. Yet, recent re-emphasis on the ecological dimensions of speciation points to a more prominent role of divergent selection in driving genetic, phenotypic, and niche divergence. The vanishing refuge model (VRM), first described by Vanzolini and Williams (1981), describes a process of diversification through climate-driven habitat fragmentation and exposure to new environments, integrating both vicariance and divergent selection. This model suggests that dynamic climates and peripheral isolates can lead to genetic and functional (i.e., ecological and phenotypic) diversity, resulting in sister taxa that occupy contrasting habitats with abutting distributions. Here, we provide predictions for populations undergoing divergence according to the VRM that encompass habitat dynamics, phylogeography, and phenotypic differentiation across populations. Such integrative analyses can, in principle, differentiate the operation of the VRM from other speciation models. We applied these principles to a lizard species, Coleodactylus meridionalis, which was used to illustrate the model in the original paper. We incorporate data on inferred historic habitat dynamics, phylogeography and thermal physiology to test for divergence between coastal and inland populations in the Atlantic Forest of Brazil. Environmental and genetic analyses are concordant with divergence through the VRM, yet physiological data are not. We emphasize the importance of multidisciplinary approaches to test this and alternative speciation models while seeking to explain the extraordinarily high genetic and phenotypic diversity of tropical biomes.
Collapse
Affiliation(s)
- Roberta Damasceno
- Museum of Vertebrate Zoology, Integrative Biology Department, University of California Berkeley Berkeley, CA, USA ; Departamento de Zoologia, Instituto de Biociências, Universidade de São Paulo São Paulo, Brazil
| | - Maria L Strangas
- Biology Department, The Graduate Center, City University of New York New York, NY, USA
| | - Ana C Carnaval
- Biology Department, The Graduate Center, City University of New York New York, NY, USA ; Biology Department, City College, City University of New York New York, NY, USA
| | - Miguel T Rodrigues
- Departamento de Zoologia, Instituto de Biociências, Universidade de São Paulo São Paulo, Brazil
| | - Craig Moritz
- Museum of Vertebrate Zoology, Integrative Biology Department, University of California Berkeley Berkeley, CA, USA ; Research School of Biology, The Australian National University Acton, ACT, Australia
| |
Collapse
|
33
|
Hansen MM, Limborg MT, Ferchaud AL, Pujolar JM. The effects of Medieval dams on genetic divergence and demographic history in brown trout populations. BMC Evol Biol 2014; 14:122. [PMID: 24903056 PMCID: PMC4106231 DOI: 10.1186/1471-2148-14-122] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Accepted: 05/30/2014] [Indexed: 12/22/2022] Open
Abstract
Background Habitat fragmentation has accelerated within the last century, but may have been ongoing over longer time scales. We analyzed the timing and genetic consequences of fragmentation in two isolated lake-dwelling brown trout populations. They are from the same river system (the Gudenå River, Denmark) and have been isolated from downstream anadromous trout by dams established ca. 600–800 years ago. For reference, we included ten other anadromous populations and two hatchery strains. Based on analysis of 44 microsatellite loci we investigated if the lake populations have been naturally genetically differentiated from anadromous trout for thousands of years, or have diverged recently due to the establishment of dams. Results Divergence time estimates were based on 1) Approximate Bayesian Computation and 2) a coalescent-based isolation-with-gene-flow model. Both methods suggested divergence times ca. 600–800 years bp, providing strong evidence for establishment of dams in the Medieval as the factor causing divergence. Bayesian cluster analysis showed influence of stocked trout in several reference populations, but not in the focal lake and anadromous populations. Estimates of effective population size using a linkage disequilibrium method ranged from 244 to > 1,000 in all but one anadromous population, but were lower (153 and 252) in the lake populations. Conclusions We show that genetic divergence of lake-dwelling trout in two Danish lakes reflects establishment of water mills and impassable dams ca. 600–800 years ago rather than a natural genetic population structure. Although effective population sizes of the two lake populations are not critically low they may ultimately limit response to selection and thereby future adaptation. Our results demonstrate that populations may have been affected by anthropogenic disturbance over longer time scales than normally assumed.
Collapse
Affiliation(s)
- Michael M Hansen
- Department of Bioscience, Aarhus University, Ny Munkegade 114, DK-8000 Aarhus C, Denmark.
| | | | | | | |
Collapse
|
34
|
Comeault AA, Soria-Carrasco V, Gompert Z, Farkas TE, Buerkle CA, Parchman TL, Nosil P. Genome-Wide Association Mapping of Phenotypic Traits Subject to a Range of Intensities of Natural Selection in Timema cristinae. Am Nat 2014; 183:711-27. [DOI: 10.1086/675497] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
|
35
|
Räsänen K, Hendry AP. Asymmetric reproductive barriers and mosaic reproductive isolation: insights from Misty lake-stream stickleback. Ecol Evol 2014; 4:1166-75. [PMID: 24772291 PMCID: PMC3997330 DOI: 10.1002/ece3.1012] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Revised: 01/30/2014] [Accepted: 01/31/2014] [Indexed: 01/25/2023] Open
Abstract
Ecological speciation seems to occur readily but is clearly not ubiquitous - and the relative contributions of different reproductive barriers remain unclear in most systems. We here investigate the potential importance of selection against migrants in lake/stream stickleback (Gasterosteus aculeatus) from the Misty Lake system, Canada. This system is of particular interest because one population contrast (Lake vs. Outlet stream) shows very low genetic and morphological divergence, whereas another population contrast (Lake vs. Inlet stream) shows dramatic genetic and morphological divergence apparently without strong and symmetric reproductive barriers. To test whether selection against migrants might solve this "conundrum of missing reproductive isolation", we performed a fully factorial reciprocal transplant experiment using 225 individually marked stickleback collected from the wild. Relative fitness of the different ecotypes (Lake, Inlet, and Outlet) was assessed based on survival and mass change in experimental enclosures. We found that Inlet fish performed poorly in the lake (selection against migrants in that direction), whereas Lake fish outperformed Inlet fish in all environments (no selection against migrants in the opposite direction). As predicted from their phenotypic and genetic similarity, Outlet and Lake fish performed similarly in all environments. These results suggest that selection against migrants is asymmetric and, together with previous work, indicates that multiple reproductive barriers contribute to reproductive isolation. Similar mosaic patterns of reproductive isolation are likely in other natural systems.
Collapse
Affiliation(s)
- Katja Räsänen
- Redpath Museum and Department of Biology, McGill University 859 Sherbrooke St. W, Montréal, QC, H3A 2K6, Canada
| | - Andrew P Hendry
- Redpath Museum and Department of Biology, McGill University 859 Sherbrooke St. W, Montréal, QC, H3A 2K6, Canada
| |
Collapse
|
36
|
Raeymaekers JAM, Konijnendijk N, Larmuseau MHD, Hellemans B, De Meester L, Volckaert FAM. A gene with major phenotypic effects as a target for selection vs. homogenizing gene flow. Mol Ecol 2013; 23:162-81. [PMID: 24192132 DOI: 10.1111/mec.12582] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2013] [Revised: 10/20/2013] [Accepted: 10/28/2013] [Indexed: 01/28/2023]
Abstract
Genes with major phenotypic effects facilitate quantifying the contribution of genetic vs. plastic effects to adaptive divergence. A classical example is Ectodysplasin (Eda), the major gene controlling lateral plate phenotype in three-spined stickleback. Completely plated marine stickleback populations evolved repeatedly towards low-plated freshwater populations, representing a prime example of parallel evolution by natural selection. However, many populations remain polymorphic for lateral plate number. Possible explanations for this polymorphism include relaxation of selection, disruptive selection or a balance between divergent selection and gene flow. We investigated 15 polymorphic stickleback populations from brackish and freshwater habitats in coastal North-western Europe. At each site, we tracked changes in allele frequency at the Eda gene between subadults in fall, adults in spring and juveniles in summer. Eda genotypes were also compared for body size and reproductive investment. We observed a fitness advantage for the Eda allele for the low morph in freshwater and for the allele for the complete morph in brackish water. Despite these results, the differentiation at the Eda gene was poorly correlated with habitat characteristics. Neutral population structure was the best predictor of spatial variation in lateral plate number, suggestive of a substantial effect of gene flow. A meta-analysis revealed that the signature of selection at Eda was weak compared to similar studies in stickleback. We conclude that a balance between divergent selection and gene flow can maintain stickleback populations polymorphic for lateral plate number and that ecologically relevant genes may not always contribute much to local adaptation, even when targeted by selection.
Collapse
Affiliation(s)
- Joost A M Raeymaekers
- Laboratory of Biodiversity and Evolutionary Genomics, University of Leuven, Ch. Deberiotstraat 32, Leuven, B-3000, Belgium; Zoological Institute, University of Basel, Vesalgasse 1, Basel, CH-4051, Switzerland
| | | | | | | | | | | |
Collapse
|
37
|
Aguirre WE, Shervette VR, Navarrete R, Calle P, Agorastos S. Morphological and Genetic Divergence of Hoplias microlepis (Characiformes: Erythrinidae) in Rivers and Artificial Impoundments of Western Ecuador. COPEIA 2013. [DOI: 10.1643/ci-12-083] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
38
|
Richter-Boix A, Quintela M, Kierczak M, Franch M, Laurila A. Fine-grained adaptive divergence in an amphibian: genetic basis of phenotypic divergence and the role of nonrandom gene flow in restricting effective migration among wetlands. Mol Ecol 2013; 22:1322-40. [DOI: 10.1111/mec.12181] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2012] [Revised: 11/10/2012] [Accepted: 11/21/2012] [Indexed: 11/30/2022]
Affiliation(s)
- Alex Richter-Boix
- Population Biology and Conservation Biology/Department of Ecology and Genetics; Evolutionary Biology Centre; Uppsala University; Norbyvägen18D 752 36 Uppsala Sweden
| | - María Quintela
- Population Biology and Conservation Biology/Department of Ecology and Genetics; Evolutionary Biology Centre; Uppsala University; Norbyvägen18D 752 36 Uppsala Sweden
- Department of Animal Biology, Plant Biology and Ecology; Faculty of Science; University of A Coruña; Campus da Zapateira 15071 A Coruña Spain
| | - Marcin Kierczak
- Department of Clinical Sciences; Computational Genetics Section; Swedish University of Agricultural Sciences; 756 51 Uppsala Sweden
| | - Marc Franch
- Department of Animal Biology; University of Barcelona; Diagonal 643 08028 Barcelona Spain
| | - Anssi Laurila
- Population Biology and Conservation Biology/Department of Ecology and Genetics; Evolutionary Biology Centre; Uppsala University; Norbyvägen18D 752 36 Uppsala Sweden
| |
Collapse
|
39
|
Ravinet M, Prodöhl PA, Harrod C. Parallel and nonparallel ecological, morphological and genetic divergence in lake-stream stickleback from a single catchment. J Evol Biol 2012. [PMID: 23199201 DOI: 10.1111/jeb.12049] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Parallel phenotypic evolution in similar environments has been well studied in evolutionary biology; however, comparatively little is known about the influence of determinism and historical contingency on the nature, extent and generality of this divergence. Taking advantage of a novel system containing multiple lake-stream stickleback populations, we examined the extent of ecological, morphological and genetic divergence between three-spined stickleback present in parapatric environments. Consistent with other lake-stream studies, we found a shift towards a deeper body and shorter gill rakers in stream fish. Morphological shifts were concurrent with changes in diet, indicated by both stable isotope and stomach contents analysis. Performing a multivariate test for shared and unique components of evolutionary response to the distance gradient from the lake, we found a strong signature of parallel adaptation. Nonparallel divergence was also present, attributable mainly to differences between river locations. We additionally found evidence of genetic substructuring across five lake-stream transitions, indicating that some level of reproductive isolation occurs between populations in these habitats. Strong correlations between pairwise measures of morphological, ecological and genetic distance between lake and stream populations supports the hypothesis that divergent natural selection between habitats drives adaptive divergence and reproductive isolation. Lake-stream stickleback divergence in Lough Neagh provides evidence for the deterministic role of selection and supports the hypothesis that parallel selection in similar environments may initiate parallel speciation.
Collapse
Affiliation(s)
- M Ravinet
- School of Biological Sciences, Queen's University Belfast, Belfast, UK.
| | | | | |
Collapse
|
40
|
Purcell KM, Hitch A, Martin S, Klerks PL, Leberg PL. The role of genetic structure in the adaptive divergence of populations experiencing saltwater intrusion due to relative sea-level rise. J Evol Biol 2012; 25:2623-32. [PMID: 23116362 DOI: 10.1111/jeb.12016] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2011] [Accepted: 09/07/2012] [Indexed: 11/28/2022]
Abstract
Saltwater intrusion into estuaries creates stressful conditions for nektonic species. Previous studies have shown that Gambusia affinis populations with exposure to saline environments develop genetic adaptations for increased survival during salinity stress. Here, we evaluate the genetic structure of G. affinis populations, previously shown to have adaptations for increased salinity tolerance, and determine the impact of selection and gene flow on structure of these populations. We found that gene flow was higher between populations experiencing different salinity regimes within an estuary than between similar marsh types in different estuaries, suggesting the development of saline-tolerant phenotypes due to local adaptation. There was limited evidence of genetic structure along a salinity gradient, and only some of the genetic variation among sites was correlated with salinity. Our results suggest limited structure, combined with selection to saltwater intrusion, results in phenotypic divergence in spite of a lack of physical barriers to gene flow.
Collapse
Affiliation(s)
- K M Purcell
- Department of Biology, University of Louisiana at Lafayette, Lafayette, LA, USA.
| | | | | | | | | |
Collapse
|
41
|
carrea C, Barriga JP, Cussac VE, Ruzzante DE. Genetic and phenotypic differentiation among Galaxias maculatus populations in a Patagonian postglacial lake system. Biol J Linn Soc Lond 2012. [DOI: 10.1111/j.1095-8312.2012.01939.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | - Juan P. Barriga
- INIBIOMA (Universidad Nacional del Comahue-CONICET) Quintral; 1250 (8400); Bariloche; RN; Argentina
| | - Victor E. Cussac
- INIBIOMA (Universidad Nacional del Comahue-CONICET) Quintral; 1250 (8400); Bariloche; RN; Argentina
| | - Daniel E. Ruzzante
- Department of Biology; Dalhousie University; Halifax; NS; B3H 4R2; Canada
| |
Collapse
|
42
|
Harris LN, Taylor EB, Tallman RF, Reist JD. Gene flow and effective population size in two life-history types of broad whitefish Coregonus nasus from the Canadian Arctic. JOURNAL OF FISH BIOLOGY 2012; 81:288-307. [PMID: 22747819 DOI: 10.1111/j.1095-8649.2012.03339.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
In this study, the magnitude and direction of gene flow and estimates of effective population sizes (N(e) ) were quantified among two life-history types (lacustrine and anadromous) of broad whitefish Coregonus nasus in the lower Mackenzie River system. The data suggest that dispersal and subsequent gene flow occurs between these groups, with the former appearing to be asymmetrical. Gene flow may potentially be directionally biased as well, a result attributed to source-sink population dynamics and the ongoing process of post-glacial colonization and contemporary range expansion. Additionally, average N(e) estimates were consistently lower for lacustrine populations of C. nasus although confidence intervals for both contemporary and historical estimates broadly overlapped. The lower average estimates of N(e) for lacustrine populations was suggested to be the result of more recent founding events following post-glacial dispersal. This study provides one of the first assessments of gene flow and N(e) in an Arctic coregonine, results that may be relevant to other freshwater and anadromous Arctic species persisting in systems near the periphery of their range.
Collapse
Affiliation(s)
- L N Harris
- Fisheries and Oceans Canada, Arctic Aquatic Research Division, 501 University Crescent, Winnipeg, MB, R3T 2N6 Canada.
| | | | | | | |
Collapse
|
43
|
Huisman J, Tufto J. COMPARISON OF NON-GAUSSIAN QUANTITATIVE GENETIC MODELS FOR MIGRATION AND STABILIZING SELECTION. Evolution 2012; 66:3444-61. [DOI: 10.1111/j.1558-5646.2012.01707.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
44
|
Roesti M, Hendry AP, Salzburger W, Berner D. Genome divergence during evolutionary diversification as revealed in replicate lake-stream stickleback population pairs. Mol Ecol 2012; 21:2852-62. [PMID: 22384978 DOI: 10.1111/j.1365-294x.2012.05509.x] [Citation(s) in RCA: 187] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Evolutionary diversification is often initiated by adaptive divergence between populations occupying ecologically distinct environments while still exchanging genes. The genetic foundations of this divergence process are largely unknown and are here explored through genome scans in multiple independent lake-stream population pairs of threespine stickleback. We find that across the pairs, overall genomic divergence is associated with the magnitude of divergence in phenotypes known to be under divergent selection. Along this same axis of increasing diversification, genomic divergence becomes increasingly biased towards the centre of chromosomes as opposed to the peripheries. We explain this pattern by within-chromosome variation in the physical extent of hitchhiking, as recombination is greatly reduced in chromosome centres. Correcting for this effect suggests that a great number of genes distributed widely across the genome are involved in the divergence into lake vs. stream habitats. Analyzing additional allopatric population pairs, however, reveals that strong divergence in some genomic regions has been driven by selection unrelated to lake-stream ecology. Our study highlights a major contribution of large-scale variation in recombination rate to generating heterogeneous genomic divergence and indicates that elucidating the genetic basis of adaptive divergence might be more challenging than currently recognized.
Collapse
Affiliation(s)
- Marius Roesti
- Zoological Institute, University of Basel, Vesalgasse 1, CH-4051 Basel, Switzerland
| | | | | | | |
Collapse
|
45
|
Urban MC, De Meester L, Vellend M, Stoks R, Vanoverbeke J. A crucial step toward realism: responses to climate change from an evolving metacommunity perspective. Evol Appl 2012; 5:154-67. [PMID: 25568038 PMCID: PMC3353337 DOI: 10.1111/j.1752-4571.2011.00208.x] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2011] [Accepted: 08/22/2011] [Indexed: 11/29/2022] Open
Abstract
We need to understand joint ecological and evolutionary responses to climate change to predict future threats to biological diversity. The 'evolving metacommunity' framework emphasizes that interactions between ecological and evolutionary mechanisms at both local and regional scales will drive community dynamics during climate change. Theory suggests that ecological and evolutionary dynamics often interact to produce outcomes different from those predicted based on either mechanism alone. We highlight two of these dynamics: (i) species interactions prevent adaptation of nonresident species to new niches and (ii) resident species adapt to changing climates and thereby prevent colonization by nonresident species. The rate of environmental change, level of genetic variation, source-sink structure, and dispersal rates mediate between these potential outcomes. Future models should evaluate multiple species, species interactions other than competition, and multiple traits. Future experiments should manipulate factors such as genetic variation and dispersal to determine their joint effects on responses to climate change. Currently, we know much more about how climates will change across the globe than about how species will respond to these changes despite the profound effects these changes will have on global biological diversity. Integrating evolving metacommunity perspectives into climate change biology should produce more accurate predictions about future changes to species distributions and extinction threats.
Collapse
Affiliation(s)
- Mark C Urban
- Department of Ecology and Evolutionary Biology, University of Connecticut Storrs, CT, USA
| | - Luc De Meester
- Laboratory of Aquatic Ecology and Evolutionary Biology, Katholieke Universiteit Leuven Leuven, Belgium
| | - Mark Vellend
- Department of Biology, Universite de Sherbrooke Sherbrooke, Quebec, Canada
| | - Robby Stoks
- Laboratory of Aquatic Ecology and Evolutionary Biology, Katholieke Universiteit Leuven Leuven, Belgium
| | - Joost Vanoverbeke
- Laboratory of Aquatic Ecology and Evolutionary Biology, Katholieke Universiteit Leuven Leuven, Belgium
| |
Collapse
|
46
|
Divergent Selection and Then What Not: The Conundrum of Missing Reproductive Isolation in Misty Lake and Stream Stickleback. INTERNATIONAL JOURNAL OF ECOLOGY 2012. [DOI: 10.1155/2012/902438] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
In ecological speciation, reproductive isolation evolves as a consequence of adaptation to different selective environments. A frequent contributor to this process is the evolution of positive assortative mate choice between ecotypes. We tested this expectation for lake and inlet stream threespine stickleback (Gasterosteus aculeatus) from the Misty system (Vancouver Island, Canada), which show strong genetically based adaptive divergence and little genetic exchange in nature. This, and work on other stickleback systems, led us to expect positive assortative mating. Yet, our standard “no-choice” laboratory experiment on common-garden fish revealed no evidence for this—despite divergence in traits typically mediating assortative mating in stickleback. These results remind us that divergent natural selection may not inevitably lead to the evolution of positive assortative mate choice. The apparent lack of strong and symmetric reproductive barriers in this system presents a conundrum: why are such barriers not evident despite strong adaptive divergence and low gene flow in nature?
Collapse
|
47
|
OŻGO MAŁGORZATA, BOGUCKI ZDZISŁAW. Colonization, stability, and adaptation in a transplant experiment of the polymorphic land snailCepaea nemoralis(Gastropoda: Pulmonata) at the edge of its geographical range. Biol J Linn Soc Lond 2011. [DOI: 10.1111/j.1095-8312.2011.01732.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
48
|
Franssen NR. Anthropogenic habitat alteration induces rapid morphological divergence in a native stream fish. Evol Appl 2011; 4:791-804. [PMID: 25568023 PMCID: PMC3352545 DOI: 10.1111/j.1752-4571.2011.00200.x] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2011] [Accepted: 06/24/2011] [Indexed: 11/29/2022] Open
Abstract
Anthropogenic habitat alteration creates novel environments that can alter selection pressures. Construction of reservoirs worldwide has disturbed riverine ecosystems by altering biotic and abiotic environments of impounded streams. Changes to fish communities in impoundments are well documented, but effects of those changes on native species persisting in reservoirs, which are presumably subjected to novel selective pressures, are largely unexplored. I assessed body shape variation of a native stream fish in reservoir habitats and streams from seven reservoir basins in the Central Plains of the USA. Body shape significantly and consistently diverged in reservoirs compared with stream habitats within reservoir basins; individuals from reservoir populations were deeper-bodied and had smaller heads compared with stream populations. Individuals from reservoir habitats also exhibited lower overall shape variation compared with stream individuals. I assessed the contribution of genotypic divergence and predator-induced phenotypic plasticity on body shape variation by rearing offspring from a reservoir and a stream population with or without a piscivorous fish. Significant population-level differences in body shape persisted in offspring, and both populations demonstrated similar predator-induced phenotypic plasticity. My results suggest that, although components of body shape are plastic, anthropogenic habitat modification may drive trait divergence in native fish populations in reservoir-altered habitats.
Collapse
|
49
|
|
50
|
Yeaman S, Chen Y, Whitlock MC. No effect of environmental heterogeneity on the maintenance of genetic variation in wing shape in Drosophila melanogaster. Evolution 2011; 64:3398-408. [PMID: 20624178 DOI: 10.1111/j.1558-5646.2010.01075.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Theory suggests that heterogeneous environments should maintain more genetic variation within populations than homogeneous environments, yet experimental evidence for this effect in quantitative traits has been inconsistent. To examine the effect of heterogeneity on quantitative genetic variation, we maintained replicate populations of Drosophila melanogaster under treatments with constant temperatures, temporally variable temperature, or spatially variable temperature with either panmictic or limited migration. Despite observing differences in fitness and divergence in several wing traits between the environments, we did not find any differences in the additive genetic variance for any wing traits among any of the treatments. Although we found an effect of gene flow constraining adaptive divergence between cages in the limited migration treatment, it did not tend to increase within-population genetic variance relative to any of the other treatments. The lack of any clear and repeatable patterns of response to heterogeneous versus homogeneous environments across several empirical studies suggests that a single general mechanism for the maintenance of standing genetic variation is unlikely; rather, the relative importance of putative mechanisms likely varies considerably from one trait and ecological context to another.
Collapse
Affiliation(s)
- Sam Yeaman
- Department of Zoology, University of British Columbia, 6270 University Blvd., Vancouver, British Columbia V6T 1Z4, Canada.
| | | | | |
Collapse
|