Recent climate change should result in expansion of species to northern or high elevation range margins, and contraction at southern and low elevation margins in the northern hemisphere, because of local extirpations or range shifts or both. We combined museum occurrence records from both the continental U.S.
View Article and Find Full Text PDFIn this study we detangled the evolutionary history of the Patagonian lizard clade Liolaemus kingii, coupling dense geographic sampling and novel computational analytical approaches. We analyzed nuclear and mitochondrial data (restriction site-associated DNA sequencing and cytochrome b) to hypothesize and evaluate species limits, phylogenetic relationships, and demographic histories. We complemented these analyses with posterior predictive simulations to assess the fit of the genomic data to the multispecies coalescent model.
View Article and Find Full Text PDFEvolutionary correlations between phenotypic and environmental traits characterize adaptive radiations. However, the lizard genus , one of the most ecologically diverse terrestrial vertebrate radiations on earth, has so far shown limited or mixed evidence of adaptive diversification in phenotype. Restricted use of comprehensive environmental data, incomplete taxonomic representation and not considering phylogenetic uncertainty may have led to contradictory evidence.
View Article and Find Full Text PDFMotivation: Transposable elements (TEs) are ubiquitous in genomes and many remain active. TEs comprise an important fraction of the transcriptomes with potential effects on the host genome, either by generating deleterious mutations or promoting evolutionary novelties. However, their functional study is limited by the difficulty in their identification and quantification, particularly in non-model organisms.
View Article and Find Full Text PDFZootaxa
January 2021
A new species of the Liolaemus capillitas clade is described. Liolaemus galactostictos sp. nov.
View Article and Find Full Text PDFRecent conceptual and methodological advances have enabled an increasing number of studies to address the problem of species delimitation in a comprehensive manner. This is of particular interest in cases of species whose divergence times are recent and/or effective population sizes are large, where the conclusions obtained from a single source of evidence may lead to erroneous estimations of true species numbers or incorrect assignment of individuals to species. Iguanian lizards of the Liolaemus kingii group (13 species) comprise an important component of the endemic fauna of Patagonia.
View Article and Find Full Text PDFBackground: The evolutionary history of southern South American organisms has been strongly influenced by Pleistocene climate oscillations. Amphibians are good models to evaluate hypotheses about the influence of these climate cycles on population structure and diversification of the biota, because they are sensitive to environmental changes and have restricted dispersal capabilities. We test hypotheses regarding putative forest refugia and expansion events associated with past climatic changes in the wood frog distributed along ∼1,000 km of length including glaciated and non-glaciated areas in southwestern Patagonia.
View Article and Find Full Text PDFSoutheast Asia hosts a rich concentration of biodiversity within multiple biodiversity hotspots. Indochina, a region with remarkably high levels of in situ diversification, possesses five major rivers (Ayeyarwady, Chiang Mai, Mekong, Red, and Salween), several of which coincide with phylogenetic breaks of terrestrial taxa. Draco maculatus possesses a range that stretches across Indochina, which widespread geographic distribution along with potential discrete variation within subspecies alludes to the possibility of this taxon constituting multiple divergent lineages.
View Article and Find Full Text PDFTraditionally focused on Amazonian and Atlantic rainforests, studies on the origins of high Neotropical biodiversity have recently shifted to also investigate biodiversity processes in the South American dry diagonal, encompassing Chaco, Cerrado savannas, and Caatinga seasonally dry tropical forests. The plateau/depression hypothesis states that riparian forests in the Brazilian Shield in central Brazil are inhabited by Pleistocene lineages, with shallow divergences and signatures of population expansion. Moreover, riparian forests may have acted as a vegetation network in the Pleistocene, allowing gene/species flow across the South American dry diagonal.
View Article and Find Full Text PDFThe clade Leiosaurae is composed of poorly-known species endemic to the southern region of South America. The difficulties of finding these lizards in the field, and their highly conserved morphology, have limited our taxonomic knowledge and understanding of their evolutionary histories. Here, we use data collected over 9 years to study the phylogenetic history, genetic diversity, and biogeographic history of almost all the southernmost species of Leiosaurae (except P.
View Article and Find Full Text PDFIn this contribution, the aspects of reptile and amphibian speciation that emerged from research performed over the past decade are reviewed. First, this study assesses how patterns and processes of speciation depend on knowing the taxonomy of the group in question, and discuss how integrative taxonomy has contributed to speciation research in these groups. This study then reviews the research on different aspects of speciation in reptiles and amphibians, including biogeography and climatic niches, ecological speciation, the relationship between speciation rates and phenotypic traits, and genetics and genomics.
View Article and Find Full Text PDFCoalescent-based algorithms coupled with the access to genome-wide data have become powerful tools for assessing questions on recent or rapid diversification, as well as delineating species boundaries in the absence of reciprocal monophyly. In southern South America, the diversification of Liolaemus lizards during the Pleistocene is well documented and has been attributed to the climatic changes that characterized this recent period of time. Past climatic changes had harsh effects at extreme latitudes, including Patagonia, but habitat changes at intermediate latitudes of South America have also been recorded, including expansion of sand fields over northern Patagonia and Pampas).
View Article and Find Full Text PDFConvergence is a pervasive phenomenon in the Tree of Life, and evolution of similar phenotypes sharing the same environmental conditions is expected in phylogenetically closely related species. In contrast, contingent factors are probably more influential in shaping phenotypic diversity for distantly related taxa. Here, we test putative convergent evolution of lizard head morphologies among relatively closely related desert dwelling species, and the very distantly related .
View Article and Find Full Text PDFDuring the speciation process sibling lineages accumulate differences in time (e.g. genetic, morphological, and/or ecological).
View Article and Find Full Text PDFThe Pleistocenic Arc Hypothesis (PAH) posits that South American Seasonally Dry Tropical Forests (SDTF) were interconnected during Pleistocene glacial periods, enabling the expansion of species ranges that were subsequently fragmented in interglacial periods, promoting speciation. The lizard genus Lygodactylus occurs in Africa, Madagascar, and South America. Compared to the high diversity of African Lygodactylus, only two species are known to occur in South America, L.
View Article and Find Full Text PDFHybridization is likely to occur more often between closely related taxa that have had insufficient time to diverge to the point of reproductive incompatibility; hybridization between deeply divergent lineages is rare. In squamate reptiles, hybridization has been proposed as a possible explanation for the extensive paraphyly observed in mitochondrial gene trees in several species complexes of the South American lizard genus Liolaemus. One of the best-documented cases is within the L.
View Article and Find Full Text PDFRapid evolutionary radiations are difficult to resolve because divergence events are nearly synchronous and gene flow among nascent species can be high, resulting in a phylogenetic "bush". Large datasets composed of sequence loci from across the genome can potentially help resolve some of these difficult phylogenetic problems. A suitable test case is the Liolaemus fitzingerii species group of lizards, which includes twelve species that are broadly distributed in Argentinean Patagonia.
View Article and Find Full Text PDFTwo new species of the Liolaemus donosobarrosi clade are described. Liolaemus tirantii sp. nov.
View Article and Find Full Text PDFWe present different approaches to a multi-locus phylogeny for the Liolaemus elongatus-kriegi group, including almost all species and recognized lineages. We sequenced two mitochondrial and five nuclear gene regions for 123 individuals from 35 taxa, and compared relationships resolved from concatenated and species tree methods. The L.
View Article and Find Full Text PDFSexes can differ in features associated with differential reproduction, which can be used during courtship or aggressive encounters. Some traits tend to evolve independently between sexes and emerge as sexually dimorphic within the organismal phenotype. We characterize such a relationship by estimating the phenotypic integration of the head morphology and modularity of the crest in the casque-headed lizards (Corytophanidae).
View Article and Find Full Text PDFThe phylogenetic relationships and biogeographic history of Caribbean island ameivas () are not well-known because of incomplete sampling, conflicting datasets, and poor support for many clades. Here, we use phylogenomic and mitochondrial DNA datasets to reconstruct a well-supported phylogeny and assess historical colonization patterns in the group. We obtained sequence data from 316 nuclear loci and one mitochondrial marker for 16 of 19 extant species of the Caribbean endemic genus .
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