Comparative studies of mortality in the wild are necessary to understand the evolution of aging; yet, ectothermic tetrapods are underrepresented in this comparative landscape, despite their... Show moreComparative studies of mortality in the wild are necessary to understand the evolution of aging; yet, ectothermic tetrapods are underrepresented in this comparative landscape, despite their suitability for testing evolutionary hypotheses. We present a study of aging rates and longevity across wild tetrapod ectotherms, using data from 107 populations (77 species) of nonavian reptiles and amphibians. We test hypotheses of how thermoregulatory mode, environmental temperature, protective phenotypes, and pace of life history contribute to demographic aging. Controlling for phylogeny and body size, ectotherms display a higher diversity of aging rates compared with endotherms and include phylogenetically widespread evidence of negligible aging. Protective phenotypes and life-history strategies further explain macroevolutionary patterns of aging. Analyzing ectothermic tetrapods in a comparative context enhances our understanding of the evolution of aging. Show less
Riemsdijk, I. van; Arntzen, J.W.; Babik, W.; Bogaerts, S.; Franzen, M.; Kalaentzis, K.; ... ; Wielstra, B.M. 2022
The ‘smooth newt’, the taxon traditionally referred to as Lissotriton vulgaris, consists of multiple morphologically distinct taxa. Given the uncertainty concerning the validity and rank of these... Show moreThe ‘smooth newt’, the taxon traditionally referred to as Lissotriton vulgaris, consists of multiple morphologically distinct taxa. Given the uncertainty concerning the validity and rank of these taxa, L. vulgaris sensu lato has often been treated as a single, polytypic species. A recent study, driven by genetic data, proposed to recognize five species, L. graecus, L. kosswigi, L. lantzi, L. schmidtleri and a more restricted L. vulgaris. The Carpathian newt L. montandoni was confirmed to be a closely related sister species. We propose to refer to this collective of six Lissotriton species as the smooth newt or Lissotriton vulgaris species complex. Guided by comprehensive genomic data from throughout the range of the smooth newt species complex we 1) delineate the distribution ranges, 2) provide a distribution database, and 3) produce distribution maps according to the format of the New Atlas of Amphibians and Reptiles of Europe, for the six constituent species. This allows us to 4) highlight regions where more research is needed to determine the position of contact zones. Show less
Riemsdijk, I. van; Arntzen, J.W.; Bogaerts, S.; Franzen, M.; Litvinchuk, S.N.; Olgun, K.; Wielstra, B.M. 2017
The banded newt (genus Ommatotriton) is widely distributed in the Near East (Anatolia, Caucasus and the Levant) - an understudied region from the perspective of phylogeography. The genus is... Show moreThe banded newt (genus Ommatotriton) is widely distributed in the Near East (Anatolia, Caucasus and the Levant) - an understudied region from the perspective of phylogeography. The genus is polytypic, but the number of species included and the phylogenetic relationships between them are not settled. We sequenced two mitochondrial and two nuclear DNA markers throughout the range of Ommatotriton. For mtDNA we constructed phylogenetic trees, estimated divergence times using fossil calibration, and investigated changes in effective population size with Bayesian skyline plots and mismatch analyses. For nuDNA we constructed phylogenetic trees and haplotype networks. Species trees were constructed for all markers and nuDNA only. Species distribution models were projected on current and Last Glacial Maximum climate layers. We confirm the presence of three Ommatotriton species: O. nesterovi, O. ophryticus and O. vittatus. These species are genetically distinct and their most recent common ancestor was dated at similar to 25 Ma (Oligocene). No evidence of recent gene flow between species was found. The species show deep intraspecific genetic divergence, represented by geographically structured clades, with crown nodes of species dated similar to 8-13 Ma (Miocene to Early Quaternary); evidence of long-term in situ evolution and survival in multiple glacial refugia. While a species tree based on nuDNA suggested a sister species relationship between O. vittatus and O. ophryticus, when mtDNA was included, phylogenetic relationships were unresolved, and we refrain from accepting a particular phylogenetic hypothesis at this stage. While species distribution models suggest reduced and fragmented ranges during the Last Glacial Maximum, we found no evidence for strong population bottlenecks. We discuss our results in the light of other phylogeographic studies from the Near East. Our study underlines the important role of the Near East in generating and sustaining biodiversity. (C) 2017 The Authors. Published by Elsevier Inc. Show less
Facultative paedomorphism is regularly observed in salamanders, including newts of the Lissotriton vulgaris group. We document the first record of paedomorphism in L. (v.) kosswigi from a locality... Show moreFacultative paedomorphism is regularly observed in salamanders, including newts of the Lissotriton vulgaris group. We document the first record of paedomorphism in L. (v.) kosswigi from a locality near Karasu, in the vicinity of Sakarya, Turkey. We compare measurements of 5 paedomorphic individuals with those of 10 metamorphic individuals from the same population and with measurements taken from the literature. Paedomorphs are on average bigger than metamorphs; intriguingly, the opposite pattern has been observed in the Turkish L. (v.) schmidtlerorum. Show less
Two and perhaps three taxa of Lissotriton newt occur in Turkey. Their species status is controversial. The distribution of these taxa and the taxonomic status of each are reviewed and discussed. A... Show moreTwo and perhaps three taxa of Lissotriton newt occur in Turkey. Their species status is controversial. The distribution of these taxa and the taxonomic status of each are reviewed and discussed. A database of 128 Turkish Lissotriton localities was compiled and species distribution models were constructed. We reiterate that the presence of L. (v.) lantzi in Turkey is disputed and needs confirmation. The range of L. (v.) kosswigi is restricted to north-western Anatolia - given the small global range of this Turkey endemic, a closer look at its conservation status is warranted. The distribution of L. v. schmidtleri covers western Asiatic and European Turkey. The findings support an allopatric distribution of the Turkish Lissotriton species. We reflect on the biological significance of previously reported morphological intermediates between L. (v.) kosswigi and L. v. schmidtleri in the light of the recent proposal to recognize kosswigi at the species level. The available data are in line with species status for L. (v.) lantzi and L. (v.) kosswigi. Although L. v. schmidtleri is a genetically diverged taxon as well, the extent of gene flow with parapatric European Lissotriton taxa is as yet unknown. Show less
The Eurasian Triturus karelinii group of crested newts comprises three distinct, geographically coherent mitochondrial DNA lineages, designated as the eastern, central and western lineage. These... Show moreThe Eurasian Triturus karelinii group of crested newts comprises three distinct, geographically coherent mitochondrial DNA lineages, designated as the eastern, central and western lineage. These three lineages are genetically as diverged as other, morphologically well-differentiated crested newt species. However, on the ground of restricted morphological studies the three lineages have been considered morphologically uniform. We analyze skull shape in the T. karelinii group using geometric morphometric techniques and interpret the results in a phylogenetic context. We found a high divergence between populations and variable patterns of sexual dimorphism within mitochondrial DNA lineages, significant divergence in skull shape including significant divergence in allometry of the ventral skull side in females, and lack of concordance between the pattern of morphological and genetic variation within lineages and between lineages. The observed pattern indicates that ecologically mediated divergences could play an important role in the evolution of skull shape. Reconstruction of the evolutionary trajectory of the T. karelinii group indicates that the eastern lineage largely retains the ancestral skull shape and that the central and western lineages possess a derived skull shape. Skull shape does not clearly support the presence of three discrete geographical groups as suggested by the mitochondrial DNA data, but the amount of shape changes between T. karelinii lineages is similar to that between T. karelinii lineages and the outgroup species, T. macedonicus. (C) 2012 Elsevier GmbH. All rights reserved. Show less