1
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Speciation in a metapopulation model upon environmental changes. Ecol Modell 2022. [DOI: 10.1016/j.ecolmodel.2022.109958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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2
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Nikolakis ZL, Orton RW, Crother BI. Fine‐scale population structure within an Eastern Nearctic snake complex (
Pituophis melanoleucus
). ZOOL SCR 2021. [DOI: 10.1111/zsc.12522] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Zachary L. Nikolakis
- Department of Biology Southeastern Louisiana University Hammond Louisina USA
- Department of Biology University of Texas at Arlington Arlington Texas USA
| | - Richard W. Orton
- Department of Biology University of Texas at Arlington Arlington Texas USA
| | - Brian I. Crother
- Department of Biology Southeastern Louisiana University Hammond Louisina USA
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3
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Significant habitat loss of the black vanilla orchid (Nigritella nigra s.l., Orchidaceae) and shifts in its pollinators availability as results of global warming. Glob Ecol Conserv 2021. [DOI: 10.1016/j.gecco.2021.e01560] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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4
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Kaiser S, Kihara TC, Brix S, Mohrbeck I, Janssen A, Jennings RM. Species boundaries and phylogeographic patterns in new species of Nannoniscus (Janiroidea: Nannoniscidae) from the equatorial Pacific nodule province inferred from mtDNA and morphology. Zool J Linn Soc 2021. [DOI: 10.1093/zoolinnean/zlaa174] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Abstract
Spatial patterns of genetic variation (based on COI and 16S mtDNA) for morphologically similar species in the isopod genus Nannoniscus G.O. Sars. 1870 were examined that occur broadly across the Clarion Clipperton Fracture Zone (CCZ). Samples were obtained from five different licence areas as well as an Area of Particular Environmental Interest (APEI-6) with sites located at various distances (a few to several hundred kilometres) from one another. Applying three different species delimitation (SD) methods (sGMYC, mPTP and ABGD) of the molecular data, we could distinguish between four and 12 different molecular taxonomic operational units (MOTUs). Morphological analyses could confirm five distinct phenotypic clades that represent species new to science and are described here: Nannoniscus brenkei sp. nov., Nannoniscus hilario sp. nov., Nannoniscus magdae sp. nov., Nannoniscus menoti sp. nov. and Nannoniscus pedro sp. nov. Despite the assumed limited dispersal capacity of Nannoniscus species, we found haplotypes of two species to be geographically widespread (up to > 1400 km apart), as opposed to several divergent clades occurring in close vicinity or even sympatry. Geographic distance appeared to explain the phylogeographic structure of Nannoniscus species to some extent, although oceanographic features and level of environmental heterogeneity were probably equally important.
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Affiliation(s)
- Stefanie Kaiser
- German Centre for Marine Biodiversity Research (DZMB), Senckenberg am Meer, c/o Center of Natural History (CeNak), Universität Hamburg, Martin-Luther-King-Platz, Hamburg, Germany
- CeNak, Universität Hamburg, Martin-Luther-King-Platz, Hamburg, Germany
| | - Terue Cristina Kihara
- German Centre for Marine Biodiversity Research (DZMB), Senckenberg am Meer, Südstrand, Wilhelmshaven, Germany
- INES Integrated Environmental Solutions UG, Südstrand, Wilhelmshaven, Germany
| | - Saskia Brix
- German Centre for Marine Biodiversity Research (DZMB), Senckenberg am Meer, c/o Center of Natural History (CeNak), Universität Hamburg, Martin-Luther-King-Platz, Hamburg, Germany
| | - Inga Mohrbeck
- German Centre for Marine Biodiversity Research (DZMB), Senckenberg am Meer, Südstrand, Wilhelmshaven, Germany
| | - Annika Janssen
- German Centre for Marine Biodiversity Research (DZMB), Senckenberg am Meer, Südstrand, Wilhelmshaven, Germany
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5
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Moreira LR, Hernandez-Baños BE, Smith BT. Spatial predictors of genomic and phenotypic variation differ in a lowland Middle American bird (Icterus gularis). Mol Ecol 2020; 29:3085-3102. [PMID: 32621770 DOI: 10.1111/mec.15536] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 06/08/2020] [Accepted: 06/24/2020] [Indexed: 12/13/2022]
Abstract
Spatial patterns of intraspecific variation are shaped by geographical distance among populations, historical changes in gene flow and interactions with local environments. Although these factors are not mutually exclusive and operate on both genomic and phenotypic variation, it is unclear how they affect these two axes of variation. We address this question by exploring the predictors of genomic and phenotypic divergence in Icterus gularis, a broadly distributed Middle American bird that exhibits marked geographical variation in body size across its range. We combined a comprehensive single nucleotide polymorphism and phenotypic data set to test whether genome-wide genetic and phenotypic differentiation are best explained by (i) isolation by distance, (ii) isolation by history or (iii) isolation by environment. We find that the pronounced genetic and phenotypic variation in I. gularis are only partially correlated and differ regarding spatial predictors. Whereas genomic variation is largely explained by historical barriers to gene flow, phenotypic diversity can be best predicted by contemporary environmental heterogeneity. Our genomic analyses reveal strong phylogeographical structure coinciding with the Chivela Pass at the Isthmus of Tehuantepec that was formed during the Pleistocene, when populations were isolated in north-south refugia. In contrast, we found a strong association between body size and environmental variables, such as temperature and precipitation. The relationship between body size and local climate is consistent with a pattern produced by either natural selection or environmental plasticity. Overall, these results provide empirical evidence for why phenotypic and genomic data are often in conflict in taxonomic and phylogeographical studies.
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Affiliation(s)
- Lucas R Moreira
- Department of Ecology, Evolution and Environmental Biology, Columbia University, New York, NY, USA.,Department of Ornithology, American Museum of Natural History, New York, NY, USA
| | | | - Brian Tilston Smith
- Department of Ornithology, American Museum of Natural History, New York, NY, USA
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6
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Myers EA, Bryson RW, Hansen RW, Aardema ML, Lazcano D, Burbrink FT. Exploring Chihuahuan Desert diversification in the gray-banded kingsnake, Lampropeltis alterna (Serpentes: Colubridae). Mol Phylogenet Evol 2019; 131:211-218. [DOI: 10.1016/j.ympev.2018.10.031] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Revised: 10/23/2018] [Accepted: 10/23/2018] [Indexed: 12/20/2022]
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8
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Abstract
Variation in diet breadth among organisms is a pervasive feature of the natural world that has resisted general explanation. In particular, trade-offs in the ability to use one resource at the expense of another have been expected but rarely detected. We explore a spatial model for the evolution of specialization, motivated by studies of plant-feeding insects. The model is neutral with respect to the causes and consequences of diet breadth: the number of hosts utilized is not constrained by trade-offs, and specialization or generalization does not confer a direct advantage with respect to the persistence of populations or the probability of diversification. We find that diet breadth evolves in ways that resemble reports from natural communities. Simulated communities are dominated by specialized species, with a predictable but less species-rich component of generalized taxa. These results raise the possibility that specialization might be a consequence of stochastic diversification dynamics acting on spatially segregated consumer-resource associations rather than a trait either favored or constrained directly by natural selection. Finally, our model generates hypotheses for global patterns of herbivore diet breadth, including a positive effect of host richness and a negative effect of evenness in host plant abundance on the number of specialized taxa.
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9
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Furstenau TN, Cartwright RA. The effect of the dispersal kernel on isolation-by-distance in a continuous population. PeerJ 2016; 4:e1848. [PMID: 27069794 PMCID: PMC4824897 DOI: 10.7717/peerj.1848] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2015] [Accepted: 03/04/2016] [Indexed: 11/29/2022] Open
Abstract
Under models of isolation-by-distance, population structure is determined by the probability of identity-by-descent between pairs of genes according to the geographic distance between them. Well established analytical results indicate that the relationship between geographical and genetic distance depends mostly on the neighborhood size of the population which represents a standardized measure of gene flow. To test this prediction, we model local dispersal of haploid individuals on a two-dimensional landscape using seven dispersal kernels: Rayleigh, exponential, half-normal, triangular, gamma, Lomax and Pareto. When neighborhood size is held constant, the distributions produce similar patterns of isolation-by-distance, confirming predictions. Considering this, we propose that the triangular distribution is the appropriate null distribution for isolation-by-distance studies. Under the triangular distribution, dispersal is uniform over the neighborhood area which suggests that the common description of neighborhood size as a measure of an effective, local panmictic population is valid for popular families of dispersal distributions. We further show how to draw random variables from the triangular distribution efficiently and argue that it should be utilized in other studies in which computational efficiency is important.
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Affiliation(s)
- Tara N Furstenau
- School of Life Sciences and the Biodesign Institute, Arizona State University , Tempe, AZ , United States of America
| | - Reed A Cartwright
- School of Life Sciences and the Biodesign Institute, Arizona State University , Tempe, AZ , United States of America
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10
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Schneider DM, Baptestini EM, de Aguiar MAM. Diploid versus haploid models of neutral speciation. J Biol Phys 2016; 42:235-45. [PMID: 26755353 DOI: 10.1007/s10867-015-9404-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2015] [Accepted: 11/15/2015] [Indexed: 11/28/2022] Open
Abstract
Neutral models of speciation based on isolation by distance and assortative mating, termed topopatric, have shown to be successful in describing abundance distributions and species-area relationships. Previous works have considered this type of process in the context of haploid genomes. Here we discuss the implementation of two schemes of dominance to analyze the effects of diploidy: a complete dominance model in which one allele dominates over the other and a perfect codominant model in which heterozygous genotypes give rise to a third phenotype. In the case of complete dominance, we observe that speciation requires stronger spatial inbreeding in comparison to the haploid model. For perfect codominance, instead, speciation demands stronger genetic assortativeness. Nevertheless, once speciation is established, the three models predict the same abundance distributions even at the quantitative level, revealing the robustness of the original mechanism to describe biodiversity features.
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Affiliation(s)
- David M Schneider
- Instituto de Física 'Gleb Wataghin', Universidade Estadual de Campinas, Unicamp, 13083-859, Campinas, SP, Brazil.
| | - Elizabeth M Baptestini
- Instituto de Física 'Gleb Wataghin', Universidade Estadual de Campinas, Unicamp, 13083-859, Campinas, SP, Brazil
| | - Marcus A M de Aguiar
- Instituto de Física 'Gleb Wataghin', Universidade Estadual de Campinas, Unicamp, 13083-859, Campinas, SP, Brazil
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11
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Láruson ÁJ, Reed FA. Stability of underdominant genetic polymorphisms in population networks. J Theor Biol 2015; 390:156-63. [PMID: 26656110 DOI: 10.1016/j.jtbi.2015.11.023] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Revised: 11/12/2015] [Accepted: 11/23/2015] [Indexed: 11/26/2022]
Abstract
Heterozygote disadvantage is potentially a potent driver of population genetic divergence. Also referred to as underdominance, this phenomena describes a situation where a genetic heterozygote has a lower overall fitness than either homozygote. Attention so far has mostly been given to underdominance within a single population and the maintenance of genetic differences between two populations exchanging migrants. Here we explore the dynamics of an underdominant system in a network of multiple discrete, yet interconnected, populations. Stability of genetic differences in response to increases in migration in various topological networks is assessed. The network topology can have a dominant and occasionally non-intuitive influence on the genetic stability of the system.
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Affiliation(s)
- Áki J Láruson
- Department of Biology, University of Hawai'i at Mānoa, Honolulu, Hawai'i 96822, United States
| | - Floyd A Reed
- Department of Biology, University of Hawai'i at Mānoa, Honolulu, Hawai'i 96822, United States.
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12
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Hubert N, Calcagno V, Etienne RS, Mouquet N. Metacommunity speciation models and their implications for diversification theory. Ecol Lett 2015; 18:864-881. [DOI: 10.1111/ele.12458] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2015] [Revised: 03/31/2015] [Accepted: 04/30/2015] [Indexed: 11/28/2022]
Affiliation(s)
- Nicolas Hubert
- Institut des Sciences de l'Evolution CNRS/IRD/UM2‐UMR5554 Université de Montpellier II Place Eugène Bataillon 34095 Montpellier Cedex 05 France
| | - Vincent Calcagno
- INRA Univ. Nice Sophia Antipolis CNRS, UMR Institut Sophia Agrobiotech 06900 Sophia Antipolis France
| | - Rampal S. Etienne
- Groningen Institute for Evolutionary Life Sciences University of Groningen PO Box 11103 9700 CC Groningen The Netherlands
| | - Nicolas Mouquet
- Institut des Sciences de l'Evolution CNRS/IRD/UM2‐UMR5554 Université de Montpellier II Place Eugène Bataillon 34095 Montpellier Cedex 05 France
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13
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Morales-Jimenez AL, Disotell T, Di Fiore A. Revisiting the phylogenetic relationships, biogeography, and taxonomy of spider monkeys (genus Ateles) in light of new molecular data. Mol Phylogenet Evol 2014; 82 Pt B:467-83. [PMID: 25451801 DOI: 10.1016/j.ympev.2014.09.019] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Revised: 09/10/2014] [Accepted: 09/19/2014] [Indexed: 12/29/2022]
Abstract
Spider monkeys (Ateles) are one of the most endangered groups of primates in the Neotropics. The genus is widely distributed from Mexico to the north of Bolivia and includes many morphologically distinct forms in terms of pelage color and patterning. The taxonomy, phylogenetic relationships, and biogeographic history of the genus have been subject to much debate, making scientific communication difficult and creating challenges for conservation actions. We extracted DNA from samples of all currently recognized species of spider monkeys collected from across the geographic range of the genus, sequenced ∼3.5 kilobases of coding sequence from the mitochondrial genome, and used this large dataset to (a) infer the phylogenetic relationships among the different forms of spider monkeys, (b) evaluate whether currently recognized species of spider monkeys form reciprocally monophyletic groups that are concordant with contemporary classifications, and (c) estimate divergence dates among the different lineages of Ateles. We found that all proposed species of spider monkeys for which we have samples from multiple localities indeed appear to form monophyletic groups. However, in contrast to previous studies, several of our analyses robustly inferred Ateles marginatus from northeast Brazil as the sister taxon to all other spider monkeys. A Bayesian dating analysis suggests that the most recent common ancestor of extant Ateles dates to ∼6.7 Ma, in the late Miocene, and most species-level splits within the genus took place in the late Pliocene, suggesting that the modern diversity in spider monkeys cannot be explained principally by isolation and divergence of populations in forest refugia during the Pleistocene. Based on our new phylogenetic inference and dating analysis, we propose a revised biogeographic scenario for the evolution of this genus.
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Affiliation(s)
- Alba Lucia Morales-Jimenez
- Center for the Study of Human Origins, New York University, Department of Anthropology, 25 Waverly Place, New York, NY 10003, United States; Fundación Biodiversa Colombia, Cra. 22 # 41 - 80, Apto. 401, Bogotá, D.C., Colombia.
| | - Todd Disotell
- Center for the Study of Human Origins, New York University, Department of Anthropology, 25 Waverly Place, New York, NY 10003, United States
| | - Anthony Di Fiore
- Center for the Study of Human Origins, New York University, Department of Anthropology, 25 Waverly Place, New York, NY 10003, United States; University of Texas at Austin, Primate Molecular Ecology and Evolution Laboratory, Department of Anthropology, 2201 Speedway Stop C3200, Austin, TX 78712, United States.
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14
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15
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Cushman SA, Max T, Meneses N, Evans LM, Ferrier S, Honchak B, Whitham TG, Allan GJ. Landscape genetic connectivity in a riparian foundation tree is jointly driven by climatic gradients and river networks. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2014; 24:1000-1014. [PMID: 25154093 DOI: 10.1890/13-1612.1] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Fremont cottonwood (Populus fremonti) is a foundation riparian tree species that drives community structure and ecosystem processes in southwestern U.S. ecosystems. Despite its ecological importance, little is known about the ecological and environmental processes that shape its genetic diversity, structure, and landscape connectivity. Here, we combined molecular analyses of 82 populations including 1312 individual trees dispersed over the species' geographical distribution. We reduced the data set to 40 populations and 743 individuals to eliminate admixture with a sibling species, and used multivariate restricted optimization and reciprocal causal modeling to evaluate the effects of river network connectivity and climatic gradients on gene flow. Our results confirmed the following: First, gene flow of Fremont cottonwood is jointly controlled by the connectivity of the river network and gradients of seasonal precipitation. Second, gene flow is facilitated by mid-sized to large rivers, and is resisted by small streams and terrestrial uplands, with resistance to gene flow decreasing with river size. Third, genetic differentiation increases with cumulative differences in winter and spring precipitation. Our results suggest that ongoing fragmentation of riparian habitats will lead to a loss of landscape-level genetic connectivity, leading to increased inbreeding and the concomitant loss of genetic diversity in a foundation species. These genetic effects will cascade to a much larger community of organisms, some of which are threatened and endangered.
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16
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Thomassen HA, Freedman AH, Brown DM, Buermann W, Jacobs DK. Regional differences in seasonal timing of rainfall discriminate between genetically distinct East African giraffe taxa. PLoS One 2013; 8:e77191. [PMID: 24194870 PMCID: PMC3806738 DOI: 10.1371/journal.pone.0077191] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2012] [Accepted: 09/08/2013] [Indexed: 11/18/2022] Open
Abstract
Masai (Giraffa tippelskirchi), Reticulated (G. reticulata) and Rothschild's (G. camelopardalis) giraffe lineages in East Africa are morphologically and genetically distinct, yet in Kenya their ranges abut. This raises the question of how divergence is maintained among populations of a large mammal capable of long-distance travel, and which readily hybridize in zoos. Here we test four hypotheses concerning the maintenance of the phylogeographic boundaries among the three taxa: 1) isolation-by-distance; 2) physical barriers to dispersal; 3) general habitat differences resulting in habitat segregation; or 4) regional differences in the seasonal timing of rainfall, and resultant timing of browse availability. We used satellite remotely sensed and climate data to characterize the environment at the locations of genotyped giraffes. Canonical variate analysis, random forest algorithms, and generalized dissimilarity modelling were employed in a landscape genetics framework to identify the predictor variables that best explained giraffes' genetic divergence. We found that regional differences in the timing of precipitation, and resulting green-up associated with the abundance of browse, effectively discriminate between taxa. Local habitat conditions, topographic and human-induced barriers, and geographic distance did not aid in discriminating among lineages. Our results suggest that selection associated with regional timing of events in the annual climatic cycle may help maintain genetic and phenotypic divergence in giraffes. We discuss potential mechanisms of maintaining divergence, and suggest that synchronization of reproduction with seasonal rainfall cycles that are geographically distinct may contribute to reproductive isolation. Coordination of weaning with green-up cycles could minimize the costs of lactation and predation on the young. Our findings are consistent with theory and empirical results demonstrating the efficacy of seasonal or phenologically dictated selection pressures in contributing to the reproductive isolation of parapatric populations.
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Affiliation(s)
- Henri A. Thomassen
- Center for Tropical Research, University of California Los Angeles, Los Angeles, California, United States of America
- * E-mail:
| | - Adam H. Freedman
- Center for Tropical Research, University of California Los Angeles, Los Angeles, California, United States of America
| | - David M. Brown
- Department of Ecology and Evolutionary Biology, University of California Los Angeles, Los Angeles, California, United States of America
| | - Wolfgang Buermann
- Center for Tropical Research, University of California Los Angeles, Los Angeles, California, United States of America
- Department of Atmospheric and Oceanic Sciences, University of California Los Angeles, Los Angeles, California, United States of America
| | - David K. Jacobs
- Department of Ecology and Evolutionary Biology, University of California Los Angeles, Los Angeles, California, United States of America
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17
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Conditions for neutral speciation via isolation by distance. J Theor Biol 2013; 335:51-6. [DOI: 10.1016/j.jtbi.2013.06.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2013] [Accepted: 06/11/2013] [Indexed: 11/19/2022]
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18
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Liebherr JK. The Mecyclothorax beetles (Coleoptera, Carabidae, Moriomorphini) of Tahiti, Society Islands. Zookeys 2013:1-170. [PMID: 24003312 PMCID: PMC3760220 DOI: 10.3897/zookeys.322.5492] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2013] [Accepted: 07/18/2013] [Indexed: 11/12/2022] Open
Abstract
The 101 species of Mecyclothorax Sharp known to inhabit Tahiti Island, French Polynesia are taxonomically revised, including 28 species that are newly described: Mecyclothorax claridgeiae sp. n., Mecyclothorax jeanyvesi sp. n., Mecyclothorax poria sp. n., Mecyclothorax aano sp. n., Mecyclothorax papau sp. n., Mecyclothorax manina sp. n., Mecyclothorax everardi sp. n., Mecyclothorax ramagei sp. n., Mecyclothorax pitohitiensis sp. n., Mecyclothorax curtisi sp. n., Mecyclothorax hoeahiti sp. n., Mecyclothorax ninamu sp. n., Mecyclothorax kokone sp. n., Mecyclothorax paahonu sp. n., Mecyclothorax kayballae sp. n., Mecyclothorax ehu sp. n., Mecyclothorax papuhiti sp. n., Mecyclothorax tuea sp. n., Mecyclothorax taatitore sp. n., Mecyclothorax konemata sp. n., Mecyclothorax arboricola sp. n., Mecyclothorax rahimata sp. n., M. oaoa sp. n., Mecyclothorax maninapopoti sp. n., Mecyclothorax hunapopoti sp. n., Mecyclothorax fefemata sp. n., Mecyclothorax maninamata sp. n., and Mecyclothorax niho sp. n. Mecyclothorax muriauxioides Perrault, 1984 is newly synonymized with Mecyclothorax muriauxi Perrault, 1978. Lectotypes are designated for: Thriscothorax altiusculus Britton, 1938; Thriscothorax bryobius Britton, 1938; Mecyclothorax globosus Britton, 1948: and Mecyclothorax sabulicola Britton, 1948. Dichotomous identification keys augmented by dorsal habitus and male aedeagal photographs are provided to the various species-groups and all included species. The spermatophore of Mecyclothorax papau sp. n. is described, with the ampulla and collar found to correspond dimensionally to the length of the internal sac flagellar plate. Variation among characters of the female reproductive tract is presented for all newly described plus other representative species comprising the radiation. Taxa are assigned to species groups, modified from the classification of G.G. Perrault, based on derived character states polarized using the Australian outgroup taxon Mecyclothorax punctipennis (MacLeay). Much of the species-level diversity on this small Pacific island is partitioned allopatrically over very small distributional ranges. No species is shared between Tahiti Nui and Tahiti Iti, and nearly all species in Tahiti Nui are geographically restricted to one ridgelike massif of that volcano. Cladistically similar species are often distributed on different massifs suggesting that vicariance associated with erosional valley formation has facilitated speciation, however several instances in which sister species occupy sympatric distributions on the same ridge system demonstrate that speciation may also occur across extremely localized landscapes. Such localized differentiation is facilitated by the low vagility of these small-bodied, flightless predators whose fragmented populations can persist and diverge within spatially limited habitat patches. The intense philopatry of Tahitian Mecyclothorax spp. coupled with the highly dissected landscape has produced the geographically densest adaptive radiation on Earth. This radiation has occurred very rapidly, with species durations averaging 300,000 yr; a speciation rate similar to that observed in Hawaiian Oliarus planthoppers and Laupala crickets, and East African Rift lake cichlid fishes.
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Affiliation(s)
- James K Liebherr
- Cornell University Insect Collection, Department of Entomology, 2144 John H. and Anna B. Comstock Hall, Cornell University, Ithaca, NY 14853-2601, USA
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19
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Guarnizo CE, Cannatella DC. Genetic divergence within frog species is greater in topographically more complex regions. J ZOOL SYST EVOL RES 2013. [DOI: 10.1111/jzs.12027] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Carlos E. Guarnizo
- Section of Integrative Biology; University of Texas at Austin; Austin TX USA
| | - David C. Cannatella
- Section of Integrative Biology; University of Texas at Austin; Austin TX USA
- Texas Natural Science Center; University of Texas at Austin; Austin TX USA
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20
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Sauer J, Oldeland J, Hausdorf B. Continuing fragmentation of a widespread species by geographical barriers as initial step in a land snail radiation on crete. PLoS One 2013; 8:e62569. [PMID: 23658748 PMCID: PMC3641037 DOI: 10.1371/journal.pone.0062569] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2013] [Accepted: 03/23/2013] [Indexed: 11/18/2022] Open
Abstract
The phylogeographic structure of the land snail Xerocrassa mesostena on Crete inferred from AFLP markers and mitochondrial cox1 sequences can be explained by three mechanisms: gene flow restriction, population expansion and leptokurtic dispersal. Gene flow restriction by geographic barriers caused subdivision of the gene pool into distinct clusters. Population expansion was probably facilitated by deforestation of Crete in the postglacial. Newly available areas were colonized by leptokurtic dispersal, i.e. slow active expansion resulting in isolation by distance within the clusters and occasional long distance dispersal events that resulted in departures from the isolation by distance model. Less than one percent of the AFLP markers show correlations with environmental variables. Random phylogeographic breaks in the distribution of the mitochondrial haplotype groups indicate that single locus markers, especially mitochondrial DNA, might result in a misleading picture of the phylogeographic structure of a species. Restriction of gene flow between metapopulations caused by geographical barriers can interact with sexual selection resulting in the differentiation of these metapopulations into separate species without noticeable ecological differentiation. Evidence for gene flow between parapatrically distributed evolutionary units representing different stages of the speciation process suggests that the ongoing process of fragmentation of the X. mesostena complex might be an example for parapatric speciation. The lack of ecological differentiation between these units confirms theoretical predictions that divergent selection for local adaptation is not required for rapid speciation.
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Affiliation(s)
- Jan Sauer
- Department of Chemical Ecology, University of Bielefeld, Bielefeld, Germany
- Zoological Museum, University of Hamburg, Hamburg, Germany
| | - Jens Oldeland
- Biodiversity, Evolution and Ecology of Plants, Biozentrum Klein Flottbek, University of Hamburg, Hamburg, Germany
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Pabijan M, Wollenberg KC, Vences M. Small body size increases the regional differentiation of populations of tropical mantellid frogs (Anura: Mantellidae). J Evol Biol 2012; 25:2310-24. [DOI: 10.1111/j.1420-9101.2012.02613.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2012] [Revised: 06/25/2012] [Accepted: 08/05/2012] [Indexed: 10/27/2022]
Affiliation(s)
| | | | - M. Vences
- Division of Evolutionary Biology; Zoological Institute; Technical University of Braunschweig; Braunschweig; Germany
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23
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Montecinos A, Broitman BR, Faugeron S, Haye PA, Tellier F, Guillemin ML. Species replacement along a linear coastal habitat: phylogeography and speciation in the red alga Mazzaella laminarioides along the south east Pacific. BMC Evol Biol 2012; 12:97. [PMID: 22731925 PMCID: PMC3483259 DOI: 10.1186/1471-2148-12-97] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2012] [Accepted: 05/24/2012] [Indexed: 11/30/2022] Open
Abstract
Background The Chilean shoreline, a nearly strait line of coast expanding across 35 latitudinal degrees, represents an interesting region to assess historical processes using phylogeographic analyses. Stretching along the temperate section of the East Pacific margin, the region is characterized by intense geologic activity and has experienced drastic geomorphological transformations linked to eustatic and isostatic changes during the Quaternary. In this study, we used two molecular markers to evaluate the existence of phylogeographic discontinuities and detect the genetic footprints of Pleistocene glaciations among Patagonian populations of Mazzaella laminarioides, a low-dispersal benthic intertidal red seaweed that inhabits along ~3,700 km of the Chilean coastal rocky shore. Results Three main genetic lineages were found within M. laminarioides. They are distributed along the Chilean coast in strict parapatry. The deep divergence among lineages suggests that they could be considered putative genetic sibling species. Unexpectedly, genetic breaks were not strictly concordant with the biogeographic breaks described in the region. A Northern lineage was restricted to a broad transition zone located between 30°S and 33°S and showed signals of a recent bottleneck. The reduction of population size could be related to warm events linked to El Niño Southern Oscillation, which is known to cause massive seaweed mortality in this region. To the south, we propose that transient habitat discontinuities driven by episodic tectonic uplifting of the shoreline around the Arauco region (37°S-38°S); one of the most active forearc-basins in the South East Pacific; could be at the origin of the Central/South genetic break. The large beaches, located around 38°S, are likely to contribute to the lineages’ integrity by limiting present gene flow. Finally, the Southern lineage, occupies an area affected by ice-cover during the last glaciations. Phylogeny suggested it is a derived clade and demographic analyses showed the lineage has a typical signature of postglacial recolonization from a northern glacial refugium area. Conclusions Even if environmental adaptation could have strengthened divergence among lineages in M. laminarioides, low dispersal capacity and small population size are sufficient to generate phylogeographic discontinuities determined by genetic drift alone. Interestingly, our results confirm that seaweed population connectivity over large geographic scales does not rely only on dispersal capacity but also seem to depend highly on substratum availability and population density of the receiving locality.
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Affiliation(s)
- Alejandro Montecinos
- Instituto de Ciencias Ambientales y Evolutivas, Universidad Austral de Chile, Campus Isla Teja, Casilla 567, Valdivia, Chile
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24
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Melián CJ, Alonso D, Allesina S, Condit RS, Etienne RS. Does sex speed up evolutionary rate and increase biodiversity? PLoS Comput Biol 2012; 8:e1002414. [PMID: 22412362 PMCID: PMC3297559 DOI: 10.1371/journal.pcbi.1002414] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2011] [Accepted: 01/20/2012] [Indexed: 01/22/2023] Open
Abstract
Most empirical and theoretical studies have shown that sex increases the rate of evolution, although evidence of sex constraining genomic and epigenetic variation and slowing down evolution also exists. Faster rates with sex have been attributed to new gene combinations, removal of deleterious mutations, and adaptation to heterogeneous environments. Slower rates with sex have been attributed to removal of major genetic rearrangements, the cost of finding a mate, vulnerability to predation, and exposure to sexually transmitted diseases. Whether sex speeds or slows evolution, the connection between reproductive mode, the evolutionary rate, and species diversity remains largely unexplored. Here we present a spatially explicit model of ecological and evolutionary dynamics based on DNA sequence change to study the connection between mutation, speciation, and the resulting biodiversity in sexual and asexual populations. We show that faster speciation can decrease the abundance of newly formed species and thus decrease long-term biodiversity. In this way, sex can reduce diversity relative to asexual populations, because it leads to a higher rate of production of new species, but with lower abundances. Our results show that reproductive mode and the mechanisms underlying it can alter the link between mutation, evolutionary rate, speciation and biodiversity and we suggest that a high rate of evolution may not be required to yield high biodiversity. The role of sex in driving genetic variation and the speed at which new species emerge has been debated for over a century. There is experimental and theoretical evidence that sex increases genetic variation and the speed at which new species emerge, although evidence that sex reduces variation and slows the formation of new species also exists. Surprisingly, given the link between sex and genetic variation, little work has been done on the impact of sex on biodiversity. In the present theoretical study we show that a faster evolutionary rate can decrease the abundance of newly formed species and thus decrease long-term biodiversity. This leads to the paradoxical result that sexual reproduction can increase genetic variation but reduce species diversity. These results suggest that reducing the rate of appearance of genetic variation and the speed at which new species emerge may increase biodiversity in the long-term. This unexpected link between reproductive mode, the speed of evolution and biodiversity suggests that a high evolutionary rate may not be required to yield a large number of species in natural ecosystems.
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Affiliation(s)
- Carlos J Melián
- National Center for Ecological Analysis and Synthesis, University of California, Santa Barbara, California, United States of America.
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25
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Puechmaille SJ, Gouilh MA, Piyapan P, Yokubol M, Mie KM, Bates PJ, Satasook C, Nwe T, Bu SSH, Mackie IJ, Petit EJ, Teeling EC. The evolution of sensory divergence in the context of limited gene flow in the bumblebee bat. Nat Commun 2011; 2:573. [PMID: 22146392 PMCID: PMC3247819 DOI: 10.1038/ncomms1582] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2011] [Accepted: 11/02/2011] [Indexed: 01/12/2023] Open
Abstract
The sensory drive theory of speciation predicts that populations of the same species inhabiting different environments can differ in sensory traits, and that this sensory difference can ultimately drive speciation. However, even in the best-known examples of sensory ecology driven speciation, it is uncertain whether the variation in sensory traits is the cause or the consequence of a reduction in levels of gene flow. Here we show strong genetic differentiation, no gene flow and large echolocation differences between the allopatric Myanmar and Thai populations of the world's smallest mammal, Craseonycteris thonglongyai, and suggest that geographic isolation most likely preceded sensory divergence. Within the geographically continuous Thai population, we show that geographic distance has a primary role in limiting gene flow rather than echolocation divergence. In line with sensory-driven speciation models, we suggest that in C. thonglongyai, limited gene flow creates the suitable conditions that favour the evolution of sensory divergence via local adaptation. Populations of the same species living in different habitats can differ in sensory traits driving speciation, but it is not known if this variation limits gene flow. Here, a genetic and acoustic study of the bumblebee bat suggests that geographic distance, instead of echolocation divergence, limits gene flow.
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Affiliation(s)
- Sébastien J Puechmaille
- School of Biology and Environmental Science & UCD Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Belfield, Dublin 4, Ireland.
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26
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de Aguiar MAM, Bar-Yam Y. Moran model as a dynamical process on networks and its implications for neutral speciation. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2011; 84:031901. [PMID: 22060397 DOI: 10.1103/physreve.84.031901] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2011] [Revised: 07/18/2011] [Indexed: 05/31/2023]
Abstract
In population genetics, the Moran model describes the neutral evolution of a biallelic gene in a population of haploid individuals subjected to mutations. We show in this paper that this model can be mapped into an influence dynamical process on networks subjected to external influences. The panmictic case considered by Moran corresponds to fully connected networks and can be completely solved in terms of hypergeometric functions. Other types of networks correspond to structured populations, for which approximate solutions are also available. This approach to the classic Moran model leads to a relation between regular networks based on spatial grids and the mechanism of isolation by distance. We discuss the consequences of this connection for topopatric speciation and the theory of neutral speciation and biodiversity. We show that the effect of mutations in structured populations, where individuals can mate only with neighbors, is greatly enhanced with respect to the panmictic case. If mating is further constrained by genetic proximity between individuals, a balance of opposing tendencies takes place: increasing diversity promoted by enhanced effective mutations versus decreasing diversity promoted by similarity between mates. Resolution of large enough opposing tendencies occurs through speciation via pattern formation. We derive an explicit expression that indicates when speciation is possible involving the parameters characterizing the population. We also show that the time to speciation is greatly reduced in comparison with the panmictic case.
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27
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Wellenreuther M, Sánchez-Guillén RA, Cordero-Rivera A, Svensson EI, Hansson B. Environmental and climatic determinants of molecular diversity and genetic population structure in a coenagrionid damselfly. PLoS One 2011; 6:e20440. [PMID: 21655216 PMCID: PMC3105071 DOI: 10.1371/journal.pone.0020440] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2010] [Accepted: 05/03/2011] [Indexed: 11/19/2022] Open
Abstract
Identifying environmental factors that structure intraspecific genetic diversity is of interest for both habitat preservation and biodiversity conservation. Recent advances in statistical and geographical genetics make it possible to investigate how environmental factors affect geographic organisation and population structure of molecular genetic diversity within species. Here we present a study on a common and wide ranging insect, the blue tailed damselfly Ischnuraelegans, which has been the target of many ecological and evolutionary studies. We addressed the following questions: (i) Is the population structure affected by longitudinal or latitudinal gradients?; (ii) Do geographic boundaries limit gene flow?; (iii) Does geographic distance affect connectivity and is there a signature of past bottlenecks?; (iv) Is there evidence of a recent range expansion and (vi) what is the effect of geography and climatic factors on population structure? We found low to moderate genetic sub-structuring between populations (mean F(ST) = 0.06, D(est) = 0.12), and an effect of longitude, but not latitude, on genetic diversity. No significant effects of geographic boundaries (e.g. water bodies) were found. F(ST)-and D(est)-values increased with geographic distance; however, there was no evidence for recent bottlenecks. Finally, we did not detect any molecular signatures of range expansions or an effect of geographic suitability, although local precipitation had a strong effect on genetic differentiation. The population structure of this small insect has probably been shaped by ecological factors that are correlated with longitudinal gradients, geographic distances, and local precipitation. The relatively weak global population structure and high degree of genetic variation within populations suggest that I. elegans has high dispersal ability, which is consistent with this species being an effective and early coloniser of new habitats.
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28
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Ecological Divergence and the Origins of Intrinsic Postmating Isolation with Gene Flow. INTERNATIONAL JOURNAL OF ECOLOGY 2011. [DOI: 10.1155/2011/435357] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The evolution of intrinsic postmating isolation has received much attention, both historically and in recent studies of speciation genes. Intrinsic isolation often stems from between-locus genetic incompatibilities, where alleles that function well within species are incompatible with one another when brought together in the genome of a hybrid. It can be difficult for such incompatibilities to originate when populations diverge with gene flow, because deleterious genotypic combinations will be created and then purged by selection. However, it has been argued that if genes underlying incompatibilities are themselves subject to divergent selection, then they might overcome gene flow to diverge between populations, resulting in the origin of incompatibilities. Nonetheless, there has been little explicit mathematical exploration of such scenarios for the origin of intrinsic incompatibilities during ecological speciation with gene flow. Here we explore theoretical models for the origin of intrinsic isolation where genes subject to divergent natural selection also affect intrinsic isolation, either directly or via linkage disequilibrium with other loci. Such genes indeed overcome gene flow, diverge between populations, and thus result in the evolution of intrinsic isolation. We also examine barriers to neutral gene flow. Surprisingly, we find that intrinsic isolation sometimes weakens this barrier, by impeding differentiation via ecologically based divergent selection.
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29
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Melián CJ, Vilas C, Baldó F, González-Ortegón E, Drake P, Williams RJ. Eco-evolutionary Dynamics of Individual-Based Food Webs. ADV ECOL RES 2011. [DOI: 10.1016/b978-0-12-386475-8.00006-x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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30
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Melián CJ, Alonso D, Vázquez DP, Regetz J, Allesina S. Frequency-dependent selection predicts patterns of radiations and biodiversity. PLoS Comput Biol 2010; 6. [PMID: 20865126 PMCID: PMC2928887 DOI: 10.1371/journal.pcbi.1000892] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2010] [Accepted: 07/16/2010] [Indexed: 11/19/2022] Open
Abstract
Most empirical studies support a decline in speciation rates through time, although evidence for constant speciation rates also exists. Declining rates have been explained by invoking pre-existing niches, whereas constant rates have been attributed to non-adaptive processes such as sexual selection and mutation. Trends in speciation rate and the processes underlying it remain unclear, representing a critical information gap in understanding patterns of global diversity. Here we show that the temporal trend in the speciation rate can also be explained by frequency-dependent selection. We construct a frequency-dependent and DNA sequence-based model of speciation. We compare our model to empirical diversity patterns observed for cichlid fish and Darwin's finches, two classic systems for which speciation rates and richness data exist. Negative frequency-dependent selection predicts well both the declining speciation rate found in cichlid fish and explains their species richness. For groups like the Darwin's finches, in which speciation rates are constant and diversity is lower, speciation rate is better explained by a model without frequency-dependent selection. Our analysis shows that differences in diversity may be driven by incipient species abundance with frequency-dependent selection. Our results demonstrate that genetic-distance-based speciation and frequency-dependent selection are sufficient to explain the high diversity observed in natural systems and, importantly, predict decay through time in speciation rate in the absence of pre-existing niches. Ecological opportunity, or filling a pre-existing unoccupied adaptive zone, is considered the dominant mechanism explaining the initial explosion of diversity. Although this type of niche filling can explain rates of diversification in some lineages, it is not sufficient for a radiation to occur. Instead of attributing the propensity to have an explosion of new species to external influences like niche availability, an alternative hypothesis can be based in frequency-dependent selection driven by the ecology in which organisms are embedded or endogenous sources mediated by gametes during fertilization. We show that genome diversification driven by higher reproductive probability of rare genotypes generates rapid initial speciation followed by a plateau with very low speciation rates, as shown by most empirical data. The absence of advantage of rare genotypes generates speciation events at constant rates. We predict decline over time and constant speciation rate in the cichlids and Darwin's finches, respectively, thus providing an alternative hypothesis for the origin of radiations and biodiversity in the absence of pre-existing niche filling. In addition to predicting observed temporal trends in diversification, our analysis also highlights new mechanistic models of evolutionary biodiversity dynamics that may become suitable to generate neutral models for testing observed patterns in speciation rates and species diversity.
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Affiliation(s)
- Carlos J Melián
- National Center for Ecological Analysis and Synthesis, University of California, Santa Barbara, Santa Barbara, California, United States of America.
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31
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Abstract
Two models for speciation via selection have been proposed. In the well-known model of 'ecological speciation', divergent natural selection between environments drives the evolution of reproductive isolation. In a second 'mutation-order' model, different, incompatible mutations (alleles) fix in different populations adapting to the same selective pressure. How to demonstrate mutation-order speciation has been unclear, although it has been argued that it can be ruled out when gene flow occurs because the same, most advantageous allele will fix in all populations. However, quantitative examination of the interaction of factors influencing the likelihood of mutation-order speciation is lacking. We used simulation models to study how gene flow, hybrid incompatibility, selective advantage, timing of origination of new mutations and an initial period of allopatric differentiation affect population divergence via the mutation-order process. We find that at least some population divergence can occur under a reasonably wide range of conditions, even with moderate gene flow. However, strong divergence (e.g. fixation of different alleles in different populations) requires very low gene flow, and is promoted when (i) incompatible mutations have similar fitness advantages, (ii) less fit mutations arise slightly earlier in evolutionary time than more fit alternatives, and (iii) allopatric divergence occurs prior to secondary contact.
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Affiliation(s)
- Patrik Nosil
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO 80309, USA.
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32
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33
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Affiliation(s)
- B M Fitzpatrick
- Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville, TN 37996, USA.
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34
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de Aguiar MAM, Baranger M, Baptestini EM, Kaufman L, Bar-Yam Y. Global patterns of speciation and diversity. Nature 2009; 460:384-7. [PMID: 19606148 DOI: 10.1038/nature08168] [Citation(s) in RCA: 140] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2009] [Accepted: 05/22/2009] [Indexed: 11/09/2022]
Abstract
In recent years, strikingly consistent patterns of biodiversity have been identified over space, time, organism type and geographical region. A neutral theory (assuming no environmental selection or organismal interactions) has been shown to predict many patterns of ecological biodiversity. This theory is based on a mechanism by which new species arise similarly to point mutations in a population without sexual reproduction. Here we report the simulation of populations with sexual reproduction, mutation and dispersal. We found simulated time dependence of speciation rates, species-area relationships and species abundance distributions consistent with the behaviours found in nature. From our results, we predict steady speciation rates, more species in one-dimensional environments than two-dimensional environments, three scaling regimes of species-area relationships and lognormal distributions of species abundance with an excess of rare species and a tail that may be approximated by Fisher's logarithmic series. These are consistent with dependences reported for, among others, global birds and flowering plants, marine invertebrate fossils, ray-finned fishes, British birds and moths, North American songbirds, mammal fossils from Kansas and Panamanian shrubs. Quantitative comparisons of specific cases are remarkably successful. Our biodiversity results provide additional evidence that species diversity arises without specific physical barriers. This is similar to heavy traffic flows, where traffic jams can form even without accidents or barriers.
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Affiliation(s)
- M A M de Aguiar
- New England Complex Systems Institute, Cambridge, Massachusetts 02138, USA
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35
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Petit RJ, Excoffier L. Gene flow and species delimitation. Trends Ecol Evol 2009; 24:386-93. [PMID: 19409650 DOI: 10.1016/j.tree.2009.02.011] [Citation(s) in RCA: 473] [Impact Index Per Article: 31.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2009] [Revised: 02/19/2009] [Accepted: 02/23/2009] [Indexed: 10/20/2022]
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