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Pilar Catalan - One of the best experts on this subject based on the ideXlab platform.
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late cretaceous early eocene origin of yams dioscorea dioscoreaceae in the laurasian palaearctic and their subsequent oligocene miocene diversification
Journal of Biogeography, 2016Co-Authors: Juan Viruel, Jose Gabriel Segarramoragues, Lauren Raz, Felix Forest, Paul Wilkin, Isabel Sanmartin, Pilar CatalanAbstract:Aim Dioscorea (Dioscoreaceae) is a predominantly Pantropical genus (< 600 species) that includes the third most important tropical tuber crop and species of pharmacological value. Fossil records from both the Northern and Southern Hemispheres were used to test hypotheses about the origin of the genus Dioscorea, and to examine potential macroevolutionary processes that led to its current distribution. Location Pantropical distribution. Methods Divergence times were estimated using the most comprehensive phylogeny of the group published to date based on plastid sequences and fossil calibrations, applying a relaxed-clock model approach. Ancestral areas and range shifts were reconstructed using time-stratified likelihood-based models, reflecting past continental connectivity and biogeographical models incorporating the spatial range of fossils. Results Fossil-informed biogeographical analysis supported colonization of the Nearctic by ancient yam lineages from the western Palaearctic and subsequent migration to the South. Most of the Pantropical South American, African and Southeast Asian lineages experienced a relatively recent diversification in the Oligocene–Miocene. Long-distance dispersals were inferred for the colonizations of the New World, Africa and Madagascar. Main conclusions Dioscorea likely originated between the Late Cretaceous and the Early Eocene in the Laurasian Palaearctic, followed by possible dispersal to South America via the Eocene North Atlantic Land Bridge.
Juan Viruel - One of the best experts on this subject based on the ideXlab platform.
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late cretaceous early eocene origin of yams dioscorea dioscoreaceae in the laurasian palaearctic and their subsequent oligocene miocene diversification
Journal of Biogeography, 2016Co-Authors: Juan Viruel, Jose Gabriel Segarramoragues, Lauren Raz, Felix Forest, Paul Wilkin, Isabel Sanmartin, Pilar CatalanAbstract:Aim Dioscorea (Dioscoreaceae) is a predominantly Pantropical genus (< 600 species) that includes the third most important tropical tuber crop and species of pharmacological value. Fossil records from both the Northern and Southern Hemispheres were used to test hypotheses about the origin of the genus Dioscorea, and to examine potential macroevolutionary processes that led to its current distribution. Location Pantropical distribution. Methods Divergence times were estimated using the most comprehensive phylogeny of the group published to date based on plastid sequences and fossil calibrations, applying a relaxed-clock model approach. Ancestral areas and range shifts were reconstructed using time-stratified likelihood-based models, reflecting past continental connectivity and biogeographical models incorporating the spatial range of fossils. Results Fossil-informed biogeographical analysis supported colonization of the Nearctic by ancient yam lineages from the western Palaearctic and subsequent migration to the South. Most of the Pantropical South American, African and Southeast Asian lineages experienced a relatively recent diversification in the Oligocene–Miocene. Long-distance dispersals were inferred for the colonizations of the New World, Africa and Madagascar. Main conclusions Dioscorea likely originated between the Late Cretaceous and the Early Eocene in the Laurasian Palaearctic, followed by possible dispersal to South America via the Eocene North Atlantic Land Bridge.
Phillip A Morin - One of the best experts on this subject based on the ideXlab platform.
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structure and phylogeography of two tropical predators spinner stenella longirostris and Pantropical spotted s attenuata dolphins from snp data
Royal Society Open Science, 2018Co-Authors: Matthew S Leslie, Phillip A MorinAbstract:Little is known about global patterns of genetic connectivity in pelagic dolphins, including how circumtropical pelagic dolphins spread globally following the rapid and recent radiation of the subfamily delphininae. In this study, we tested phylogeographic hypotheses for two circumtropical species, the spinner dolphin ( Stenella longirostris ) and the Pantropical spotted dolphin ( Stenella attenuata ), using more than 3000 nuclear DNA single nucleotide polymorphisms (SNPs) in each species. Analyses for population structure indicated significant genetic differentiation between almost all subspecies and populations in both species. Bayesian phylogeographic analyses of spinner dolphins showed deep divergence between Indo-Pacific, Atlantic and eastern tropical Pacific Ocean (ETP) lineages. Despite high morphological variation, our results show very close relationships between endemic ETP spinner subspecies in relation to global diversity. The dwarf spinner dolphin is a monophyletic subspecies nested within a major clade of Pantropical spinner dolphins from the Indian and western Pacific Ocean populations. Population-level division among the dwarf spinner dolphins was detected—with the northern Australia population being very different from that in Indonesia. In contrast to spinner dolphins, the major boundary for spotted dolphins is between offshore and coastal habitats in the ETP, supporting the current subspecies-level taxonomy. Comparing these species underscores the different scale at which population structure can arise, even in species that are similar in habitat (i.e. pelagic) and distribution.
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using genome wide snps to detect structure in high diversity and low divergence populations of severely impacted eastern tropical pacific spinner stenella longirostris and Pantropical spotted dolphins s attenuata
Frontiers in Marine Science, 2016Co-Authors: Matthew S Leslie, Phillip A MorinAbstract:Millions of spinner (Stenella longirostris) and Pantropical spotted dolphins (Stenella attenuata) died since the 1960’s as bycatch in tuna nets in the eastern tropical Pacific Ocean. Despite three decades of protection, they show little-to-no sign of recovery (although recent fisheries-independent abundance estimates are not available). In efforts to establish biologically meaningful management boundaries for recovery, endemic subspecies and multiple stocks have been proposed. However, genetic differentiation among most of these units has been difficult to identify, possibly due to low statistical power stemming from large historical abundances, ongoing gene flow, and recent divergence. We tested for genetic structure at multiple hierarchical levels by analyzing the largest dataset to date brought to bear on these questions. Single nucleotide polymorphisms (SNPs) were collected from nuclear DNA regions associated with the restriction enzyme site PstI from 72 spinner dolphins and 58 Pantropical spotted dolphins using genotype-by-sequencing (GBS). Our results support the current subspecies for both species and indicate stock-level separation for Tres Marias spinner dolphins and the two offshore Pantropical spotted dolphin stocks in this area. Although bycatch has been reduced a small fraction of pre-protection levels, incidental mortality continues to impact these populations. Our results are important for the ongoing management and recovery of these highly-impacted pelagic dolphins in the eastern tropical Pacific Ocean.
Erik F Smets - One of the best experts on this subject based on the ideXlab platform.
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(page number not for citation purposes) BMC Evolutionary Biology Open AccessResearch article Diversification of myco-heterotrophic angiosperms: Evidence from
2015Co-Authors: Vincent Merckx, Suzy Huysmans, Lars W Chatrou, Benny Lemaire, Moses N Sainge, Erik F SmetsAbstract:Background: Myco-heterotrophy evolved independently several times during angiosperm evolution. Although many species of myco-heterotrophic plants are highly endemic and long-distance dispersal seems unlikely, some genera are widely dispersed and have Pantropical distributions, often with large disjunctions. Traditionally this has been interpreted as evidence for an old age of these taxa. However, due to their scarcity and highly reduced plastid genomes our understanding about the evolutionary histories of the angiosperm myco-heterotrophic groups is poor. Results: We provide a hypothesis for the diversification of the myco-heterotrophic family Burmanniaceae. Phylogenetic inference, combined with biogeographical analyses, molecular divergence time estimates, and diversification analyses suggest that Burmanniaceae originated in West Gondwana and started to diversify during the Late Cretaceous. Diversification and migration of the species-rich Pantropical genera Burmannia and Gymnosiphon display congruent patterns. Diversification began during the Eocene, when global temperatures peaked and tropical forests occurred at low latitudes. Simultaneous migration from the New to the Old World in Burmanni
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Diversification of myco-heterotrophic angiosperms: Evidence from Burmanniaceae
BMC Evolutionary Biology, 2008Co-Authors: Vincent Merckx, Suzy Huysmans, Lars W Chatrou, Benny Lemaire, Moses N Sainge, Erik F SmetsAbstract:Background Myco-heterotrophy evolved independently several times during angiosperm evolution. Although many species of myco-heterotrophic plants are highly endemic and long-distance dispersal seems unlikely, some genera are widely dispersed and have Pantropical distributions, often with large disjunctions. Traditionally this has been interpreted as evidence for an old age of these taxa. However, due to their scarcity and highly reduced plastid genomes our understanding about the evolutionary histories of the angiosperm myco-heterotrophic groups is poor. Results We provide a hypothesis for the diversification of the myco-heterotrophic family Burmanniaceae. Phylogenetic inference, combined with biogeographical analyses, molecular divergence time estimates, and diversification analyses suggest that Burmanniaceae originated in West Gondwana and started to diversify during the Late Cretaceous. Diversification and migration of the species-rich Pantropical genera Burmannia and Gymnosiphon display congruent patterns. Diversification began during the Eocene, when global temperatures peaked and tropical forests occurred at low latitudes. Simultaneous migration from the New to the Old World in Burmannia and Gymnosiphon occurred via boreotropical migration routes. Subsequent Oligocene cooling and breakup of boreotropical flora ended New-Old World migration and caused a gradual decrease in diversification rate in Burmanniaceae. Conclusion Our results indicate that extant diversity and Pantropical distribution of myco-heterotrophic Burmanniaceae is the result of diversification and boreotropical migration during the Eocene when tropical rain forest expanded dramatically.
Matthew S Leslie - One of the best experts on this subject based on the ideXlab platform.
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structure and phylogeography of two tropical predators spinner stenella longirostris and Pantropical spotted s attenuata dolphins from snp data
Royal Society Open Science, 2018Co-Authors: Matthew S Leslie, Phillip A MorinAbstract:Little is known about global patterns of genetic connectivity in pelagic dolphins, including how circumtropical pelagic dolphins spread globally following the rapid and recent radiation of the subfamily delphininae. In this study, we tested phylogeographic hypotheses for two circumtropical species, the spinner dolphin ( Stenella longirostris ) and the Pantropical spotted dolphin ( Stenella attenuata ), using more than 3000 nuclear DNA single nucleotide polymorphisms (SNPs) in each species. Analyses for population structure indicated significant genetic differentiation between almost all subspecies and populations in both species. Bayesian phylogeographic analyses of spinner dolphins showed deep divergence between Indo-Pacific, Atlantic and eastern tropical Pacific Ocean (ETP) lineages. Despite high morphological variation, our results show very close relationships between endemic ETP spinner subspecies in relation to global diversity. The dwarf spinner dolphin is a monophyletic subspecies nested within a major clade of Pantropical spinner dolphins from the Indian and western Pacific Ocean populations. Population-level division among the dwarf spinner dolphins was detected—with the northern Australia population being very different from that in Indonesia. In contrast to spinner dolphins, the major boundary for spotted dolphins is between offshore and coastal habitats in the ETP, supporting the current subspecies-level taxonomy. Comparing these species underscores the different scale at which population structure can arise, even in species that are similar in habitat (i.e. pelagic) and distribution.
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using genome wide snps to detect structure in high diversity and low divergence populations of severely impacted eastern tropical pacific spinner stenella longirostris and Pantropical spotted dolphins s attenuata
Frontiers in Marine Science, 2016Co-Authors: Matthew S Leslie, Phillip A MorinAbstract:Millions of spinner (Stenella longirostris) and Pantropical spotted dolphins (Stenella attenuata) died since the 1960’s as bycatch in tuna nets in the eastern tropical Pacific Ocean. Despite three decades of protection, they show little-to-no sign of recovery (although recent fisheries-independent abundance estimates are not available). In efforts to establish biologically meaningful management boundaries for recovery, endemic subspecies and multiple stocks have been proposed. However, genetic differentiation among most of these units has been difficult to identify, possibly due to low statistical power stemming from large historical abundances, ongoing gene flow, and recent divergence. We tested for genetic structure at multiple hierarchical levels by analyzing the largest dataset to date brought to bear on these questions. Single nucleotide polymorphisms (SNPs) were collected from nuclear DNA regions associated with the restriction enzyme site PstI from 72 spinner dolphins and 58 Pantropical spotted dolphins using genotype-by-sequencing (GBS). Our results support the current subspecies for both species and indicate stock-level separation for Tres Marias spinner dolphins and the two offshore Pantropical spotted dolphin stocks in this area. Although bycatch has been reduced a small fraction of pre-protection levels, incidental mortality continues to impact these populations. Our results are important for the ongoing management and recovery of these highly-impacted pelagic dolphins in the eastern tropical Pacific Ocean.
