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Craig Moritz - One of the best experts on this subject based on the ideXlab platform.
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comparative multi locus phylogeography confirms multiple Vicariance events in co distributed rainforest frogs
Proceedings of The Royal Society B: Biological Sciences, 2012Co-Authors: Rayna C Bell, Michael J Hickerson, Jason B Mackenzie, Krystle L Chavarria, Michael J Cunningham, Stephen E Williams, Craig MoritzAbstract:Though Pleistocene refugia are frequently cited as drivers of species diversification, comparisons of molecular divergence among sister species typically indicate a continuum of divergence times from the Late Miocene, rather than a clear pulse of speciation events at the Last Glacial Maximum. Community-scale inference methods that explicitly test for multiple Vicariance events, and account for differences in ancestral effective population size and gene flow, are well suited for detecting heterogeneity of species' responses to past climate fluctuations. We apply this approach to multi-locus sequence data from five co-distributed frog species endemic to the Wet Tropics rainforests of northeast Australia. Our results demonstrate at least two episodes of Vicariance owing to climate-driven forest contractions: one in the Early Pleistocene and the other considerably older. Understanding how repeated cycles of rainforest contraction and expansion differentially affected lineage divergence among co-distributed species provides a framework for identifying evolutionary processes that underlie population divergence and speciation.
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comparative phylogeographic summary statistics for testing simultaneous Vicariance
Molecular Ecology, 2005Co-Authors: Michael J Hickerson, Gaynor Dolman, Craig MoritzAbstract:Testing for simultaneous Vicariance across comparative phylogeographic data sets is a notoriously difficult problem hindered by mutational variance, the coalescent variance, and variability across pairs of sister taxa in parameters that affect genetic divergence. We simulate Vicariance to characterize the behaviour of several commonly used summary statistics across a range of divergence times, and to characterize this behaviour in comparative phylogeographic datasets having multiple taxon-pairs. We found Tajima’s D to be relatively uncorrelated with other summary statistics across divergence times, and using simple hypothesis testing of simultaneous Vicariance given variable population sizes, we counter-intuitively found that the variance across taxon pairs in Nei and Li’s net nucleotide divergence (π π π net ), a common measure of population divergence, is often inferior to using the variance in Tajima’s D across taxon pairs as a test statistic to distinguish ancient simultaneous Vicariance from variable Vicariance histories. The opposite and more intuitive pattern is found for testing more recent simultaneous Vicariance, and overall we found that depending on the timing of Vicariance, one of these two test statistics can achieve high statistical power for rejecting simultaneous Vicariance, given a reasonable number of intron loci (> 5 loci, 400 bp) and a range of conditions. These results suggest that components of these two composite summary statistics should be used in future simulation-based methods which can simultaneously use a pool of summary statistics to test comparative the phylogeographic hypotheses we consider here.
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molecular support for Vicariance as a source of diversity in rainforest
Proceedings of The Royal Society B: Biological Sciences, 1995Co-Authors: Leo Joseph, Craig Moritz, Andrew F HugallAbstract:The origin of high diversity in tropical rainforests is attributed to divergence amongst relatively mesic, late Pleistocene refuges. To test this hypothesis we analysed sequence variation within the mitochondrial DNA of populations of six rainforest-dwelling vertebrate species (one lizard and five birds) in the Wet Tropical rainforests of northeastern Australia. Vicariance among historical refuges was indicated by geographically congruent variation across a historical climatic barrier previously predicted by modelling. Sequence divergence across the barrier varied widely, being highest in species with lowest vagility and greatest restriction to rainforest. A high altitude, rainforest-restricted species was exceptional in lacking mtDNA variation. These data support the suggested role of Vicariance in promoting evolutionary diversity in rainforests but also indicate variation in the timing of Vicariance events, with most speciation or divergence events occurring well before the late Pleistocene. The relation between the amount of molecular divergence and current ecology suggests a sequence of isolation events, perhaps of increasing severity, occurring between the late Tertiary and the late Pleistocene.
Ulf Swenson - One of the best experts on this subject based on the ideXlab platform.
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Metapopulation Vicariance, Age of Island Taxa and Dispersal: A Case Study Using the Pacific Plant Genus Planchonella (Sapotaceae).
Systematic Biology, 2019Co-Authors: Ulf Swenson, J. Christopher Havran, Jérôme Munzinger, Stephen Mcloughlin, Stephan NylinderAbstract:Oceanic islands originate from volcanism or tectonic activity without connections to continental landmasses, are colonized by organisms, and eventually vanish due to erosion and subsidence. Colonization of oceanic islands occurs through long-distance dispersals (LDDs) or metapopulation Vicariance, the latter resulting in lineages being older than the islands they inhabit. If metapopulation Vicariance is valid, island ages cannot be reliably used to provide maximum age constraints for molecular dating. We explore the relationships between the ages of members of a widespread plant genus (Planchonella, Sapotaceae) and their host islands across the Pacific to test various assumptions of dispersal and metapopulation Vicariance. We sampled three nuclear DNA markers from 156 accessions representing some 100 Sapotaceae taxa, and analyzed these in BEAST with a relaxed clock to estimate divergence times and with a phylogeographic diffusion model to estimate range expansions over time. The phylogeny was calibrated with a secondary point (the root) and fossils from New Zealand. The dated phylogeny reveals that the ages of Planchonella species are, in most cases, consistent with the ages of the islands they inhabit. Planchonella is inferred to have originated in the Sahul Shelf region, to which it back-dispersed multiple times. Fiji has been an important source for range expansion in the Pacific for the past 23 myr. Our analyses reject metapopulation Vicariance in all cases tested, including between oceanic islands, evolution of an endemic Fiji–Vanuatu flora, and westward rollback Vicariance between Vanuatu and the Loyalty Islands. Repeated dispersal is the only mechanism able to explain the empirical data. The longest (8900 km) identified dispersal is between Palau in the Pacific and the Seychelles in the Indian Ocean, estimated at 2.2 Ma (0.4–4.8 Ma). The first split in a Hawaiian lineage (P. sandwicensis) matches the age of Necker Island (11.0 Ma), when its ancestor diverged into two species that are distinguished by purple and yellow fruits. Subsequent establishment across the Hawaiian archipelago supports, in part, progression rule colonization. In summary, we found no explanatory power in metapopulation Vicariance and conclude that Planchonella has expanded its range across the Pacific by LDD. We contend that this will be seen in many other groups when analyzed in detail.
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Vicariance or long distance dispersal historical biogeography of the pantropical subfamily chrysophylloideae sapotaceae
Journal of Biogeography, 2011Co-Authors: Igor V Bartish, Alexandre Antonelli, James E Richardson, Ulf SwensonAbstract:Aim Continental disjunctions in pantropical taxa have been explained by Vicariance or long-distance dispersal. The relative importance of these explanations in shaping current distributions may vary, depending on historical backgrounds or biological characteristics of particular taxa. We aimed to determine the geographical origin of the pantropical subfamily Chrysophylloideae (Sapotaceae) and the roles Vicariance and dispersal have played in shaping its modern distribution. Location Tropical areas of Africa, Australasia and South America.
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Vicariance or long‐distance dispersal: historical biogeography of the pantropical subfamily Chrysophylloideae (Sapotaceae)
Journal of Biogeography, 2010Co-Authors: Igor V Bartish, Alexandre Antonelli, James E Richardson, Ulf SwensonAbstract:Aim Continental disjunctions in pantropical taxa have been explained by Vicariance or long-distance dispersal. The relative importance of these explanations in shaping current distributions may vary, depending on historical backgrounds or biological characteristics of particular taxa. We aimed to determine the geographical origin of the pantropical subfamily Chrysophylloideae (Sapotaceae) and the roles Vicariance and dispersal have played in shaping its modern distribution. Location Tropical areas of Africa, Australasia and South America.
Ullasa Kodandaramaiah - One of the best experts on this subject based on the ideXlab platform.
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use of dispersal Vicariance analysis in biogeography a critique
Journal of Biogeography, 2009Co-Authors: Ullasa KodandaramaiahAbstract:Aim Analytical methods are commonly used to identify historical processes of Vicariance and dispersal in the evolution of taxa. Currently, dispersal-Vicariance analysis implemented in the software ...
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Use of dispersal–Vicariance analysis in biogeography – a critique
Journal of Biogeography, 2009Co-Authors: Ullasa KodandaramaiahAbstract:Aim Analytical methods are commonly used to identify historical processes of Vicariance and dispersal in the evolution of taxa. Currently, dispersal-Vicariance analysis implemented in the software ...
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The dispersal–Vicariance pendulum and butterfly biogeography
2009Co-Authors: Ullasa KodandaramaiahAbstract:The relative importance of dispersal and Vicariance in speciation is a subject of long standing debate. The earliest historical biogeographers invoked dispersal to explain disjunct distributions. W ...
Michael J Hickerson - One of the best experts on this subject based on the ideXlab platform.
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comparative multi locus phylogeography confirms multiple Vicariance events in co distributed rainforest frogs
Proceedings of The Royal Society B: Biological Sciences, 2012Co-Authors: Rayna C Bell, Michael J Hickerson, Jason B Mackenzie, Krystle L Chavarria, Michael J Cunningham, Stephen E Williams, Craig MoritzAbstract:Though Pleistocene refugia are frequently cited as drivers of species diversification, comparisons of molecular divergence among sister species typically indicate a continuum of divergence times from the Late Miocene, rather than a clear pulse of speciation events at the Last Glacial Maximum. Community-scale inference methods that explicitly test for multiple Vicariance events, and account for differences in ancestral effective population size and gene flow, are well suited for detecting heterogeneity of species' responses to past climate fluctuations. We apply this approach to multi-locus sequence data from five co-distributed frog species endemic to the Wet Tropics rainforests of northeast Australia. Our results demonstrate at least two episodes of Vicariance owing to climate-driven forest contractions: one in the Early Pleistocene and the other considerably older. Understanding how repeated cycles of rainforest contraction and expansion differentially affected lineage divergence among co-distributed species provides a framework for identifying evolutionary processes that underlie population divergence and speciation.
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comparative phylogeographic summary statistics for testing simultaneous Vicariance
Molecular Ecology, 2005Co-Authors: Michael J Hickerson, Gaynor Dolman, Craig MoritzAbstract:Testing for simultaneous Vicariance across comparative phylogeographic data sets is a notoriously difficult problem hindered by mutational variance, the coalescent variance, and variability across pairs of sister taxa in parameters that affect genetic divergence. We simulate Vicariance to characterize the behaviour of several commonly used summary statistics across a range of divergence times, and to characterize this behaviour in comparative phylogeographic datasets having multiple taxon-pairs. We found Tajima’s D to be relatively uncorrelated with other summary statistics across divergence times, and using simple hypothesis testing of simultaneous Vicariance given variable population sizes, we counter-intuitively found that the variance across taxon pairs in Nei and Li’s net nucleotide divergence (π π π net ), a common measure of population divergence, is often inferior to using the variance in Tajima’s D across taxon pairs as a test statistic to distinguish ancient simultaneous Vicariance from variable Vicariance histories. The opposite and more intuitive pattern is found for testing more recent simultaneous Vicariance, and overall we found that depending on the timing of Vicariance, one of these two test statistics can achieve high statistical power for rejecting simultaneous Vicariance, given a reasonable number of intron loci (> 5 loci, 400 bp) and a range of conditions. These results suggest that components of these two composite summary statistics should be used in future simulation-based methods which can simultaneously use a pool of summary statistics to test comparative the phylogeographic hypotheses we consider here.
Benjamin P Keck - One of the best experts on this subject based on the ideXlab platform.
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dispersal Vicariance and timing of diversification in nothonotus darters
Molecular Ecology, 2005Co-Authors: Thomas J. Near, Benjamin P KeckAbstract:The species diversity of North American freshwater fishes is unparalleled among temperate regions of the planet. This diversity is concentrated in the Central Highlands of eastern North America and this distribution pattern has inspired different models involving either dispersal or Vicariance to explain the high species diversity of North American fishes. The most popular of these models is the Central Highlands Vicariance hypothesis (CHVH), which proposes an ancient and diverse widespread fauna that existed across a previously continuous highland landscape that is much different from today. The mechanisms of isolation in the CHVH involve specific instances of Vicariance that affected several diverse lineages of Central Highlands fishes. We tested predictions of the CHVH and alternative models using a cytochrome b -inferred phylogeny of the darter clade Nothonotus . A Bayesian mixed-model method was used for phylogenetic analysis. The phylogenetic data set included all 20 recognized Nothonotus species, and most species were represented with multiple sequences. We were able to convert genetic branch lengths to absolute age using external fossil calibrations in the freshwater perciform fish clade Centrarchidae. Using a well-resolved Nothonotus phylogeny and divergence time estimates, we identify equal numbers of instances of both Vicariance and dispersal among disjunct regions of the Central Highlands, biogeographic pseudocongruence, rather recent speciation in Nothonotus , and a surprisingly large amount of speciation within highland areas. With regard to Nothonotus , previous Central Highlands biogeographic models offer little in the way of providing possible mechanisms responsible for diversification in the clade. Patterns of speciation in Nothonotus are similar to those discovered in recent efforts that have included speciation as a parameter into classic models of island biogeography.
