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1.
Emerg Infect Dis ; 28(10): 2064-2068, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36148931

RESUMO

The fungus Ophiodimyces ophiodiicola is the etiologic agent of snake fungal disease. Recent findings date US occurrence at least as far back as 1945. We analyzed 22 free-ranging snakes with gross lesions consistent with snake fungal disease from museum collections from Europe. We found 5 positive samples, the oldest collected in 1959.


Assuntos
Micoses , Serpentes , Animais , Europa (Continente)/epidemiologia , Fungos , Micoses/epidemiologia , Micoses/microbiologia , Micoses/veterinária , Serpentes/microbiologia
2.
Sci Rep ; 12(1): 12013, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35853951

RESUMO

Rivers are known to act as biogeographic barriers in several strictly terrestrial taxa, while possibly serving as conduits of dispersal for freshwater-tolerant or -dependent species. However, the influence of river systems on genetic diversity depends on taxa-specific life history traits as well as other geographic factors. In amphibians, several studies have demonstrated that river systems have only minor influence on their divergence. Here, we assess the role of the paleodrainage systems of the Sunda region (with a focus on the island of Sumatra) in shaping the evolutionary history of two genera of frogs (Sumaterana and Wijayarana) whose tadpoles are highly dependent on cascading stream habitats. Our phylogenetic results show no clear association between the genetic diversification patterns of both anurans genera and the existence of paleodrainage systems. Time-calibrated phylogenies and biogeographical models suggest that these frogs colonized Sumatra and diversified on the island before the occurrence of the Pleistocene drainage systems. Both genera demonstrate phylogenetic structuring along a north-south geographic axis, the temporal dynamics of which coincide with the geological chronology of proto Sumatran and -Javan volcanic islands. Our results also highlight the chronic underestimation of Sumatran biodiversity and call for more intense sampling efforts on the island.


Assuntos
Biodiversidade , Evolução Biológica , Animais , Anuros/genética , Larva/genética , Filogenia , Filogeografia
3.
Nature ; 607(7918): 313-320, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35768506

RESUMO

The grey wolf (Canis lupus) was the first species to give rise to a domestic population, and they remained widespread throughout the last Ice Age when many other large mammal species went extinct. Little is known, however, about the history and possible extinction of past wolf populations or when and where the wolf progenitors of the present-day dog lineage (Canis familiaris) lived1-8. Here we analysed 72 ancient wolf genomes spanning the last 100,000 years from Europe, Siberia and North America. We found that wolf populations were highly connected throughout the Late Pleistocene, with levels of differentiation an order of magnitude lower than they are today. This population connectivity allowed us to detect natural selection across the time series, including rapid fixation of mutations in the gene IFT88 40,000-30,000 years ago. We show that dogs are overall more closely related to ancient wolves from eastern Eurasia than to those from western Eurasia, suggesting a domestication process in the east. However, we also found that dogs in the Near East and Africa derive up to half of their ancestry from a distinct population related to modern southwest Eurasian wolves, reflecting either an independent domestication process or admixture from local wolves. None of the analysed ancient wolf genomes is a direct match for either of these dog ancestries, meaning that the exact progenitor populations remain to be located.


Assuntos
Cães , Genoma , Genômica , Filogenia , Lobos , África , Animais , DNA Antigo/análise , Cães/genética , Domesticação , Europa (Continente) , Genoma/genética , História Antiga , Oriente Médio , Mutação , América do Norte , Seleção Genética , Sibéria , Proteínas Supressoras de Tumor/genética , Lobos/classificação , Lobos/genética
4.
BMC Ecol Evol ; 22(1): 37, 2022 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-35346025

RESUMO

BACKGROUND: The 16S mitochondrial rRNA gene is the most widely sequenced molecular marker in amphibian systematic studies, making it comparable to the universal CO1 barcode that is more commonly used in other animal groups. However, studies employ different primer combinations that target different lengths/regions of the 16S gene ranging from complete gene sequences (~ 1500 bp) to short fragments (~ 500 bp), the latter of which is the most ubiquitously used. Sequences of different lengths are often concatenated, compared, and/or jointly analyzed to infer phylogenetic relationships, estimate genetic divergence (p-distances), and justify the recognition of new species (species delimitation), making the 16S gene region, by far, the most influential molecular marker in amphibian systematics. Despite their ubiquitous and multifarious use, no studies have ever been conducted to evaluate the congruence and performance among the different fragment lengths. RESULTS: Using empirical data derived from both Sanger-based and genomic approaches, we show that full-length 16S sequences recover the most accurate phylogenetic relationships, highest branch support, lowest variation in genetic distances (pairwise p-distances), and best-scoring species delimitation partitions. In contrast, widely used short fragments produce inaccurate phylogenetic reconstructions, lower and more variable branch support, erratic genetic distances, and low-scoring species delimitation partitions, the numbers of which are vastly overestimated. The relatively poor performance of short 16S fragments is likely due to insufficient phylogenetic information content. CONCLUSIONS: Taken together, our results demonstrate that short 16S fragments are unable to match the efficacy achieved by full-length sequences in terms of topological accuracy, heuristic branch support, genetic divergences, and species delimitation partitions, and thus, phylogenetic and taxonomic inferences that are predicated on short 16S fragments should be interpreted with caution. However, short 16S fragments can still be useful for species identification, rapid assessments, or definitively coupling complex life stages in natural history studies and faunal inventories. While the full 16S sequence performs best, it requires the use of several primer pairs that increases cost, time, and effort. As a compromise, our results demonstrate that practitioners should utilize medium-length primers in favor of the short-fragment primers because they have the potential to markedly improve phylogenetic inference and species delimitation without additional cost.


Assuntos
Genes Mitocondriais , RNA Ribossômico , Anfíbios/genética , Animais , Filogenia , RNA Ribossômico 16S/genética
5.
Mol Phylogenet Evol ; 163: 107210, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34029720

RESUMO

One of the most urgent contemporary tasks for taxonomists and evolutionary biologists is to estimate the number of species on earth. Recording alpha diversity is crucial for protecting biodiversity, especially in areas of elevated species richness, which coincide geographically with increased anthropogenic environmental pressures - the world's so-called biodiversity hotspots. Although the distribution of Puddle frogs of the genus Occidozyga in South and Southeast Asia includes five biodiversity hotspots, the available data on phylogeny, species diversity, and biogeography are surprisingly patchy. Samples analyzed in this study were collected throughout Southeast Asia, with a primary focus on Sundaland and the Philippines. A mitochondrial gene region comprising ~ 2000 bp of 12S and 16S rRNA with intervening tRNA Valine and three nuclear loci (BDNF, NTF3, POMC) were analyzed to obtain a robust, time-calibrated phylogenetic hypothesis. We found a surprisingly high level of genetic diversity within Occidozyga, based on uncorrected p-distance values corroborated by species delimitation analyses. This extensive genetic diversity revealed 29 evolutionary lineages, defined by the > 5% uncorrected p-distance criterion for the 16S rRNA gene, suggesting that species diversity in this clade of phenotypically homogeneous forms probably has been underestimated. The comparison with results of other anuran groups leads to the assumption that anuran species diversity could still be substantially underestimated in Southeast Asia in general. Many genetically divergent lineages of frogs are phenotypically similar, indicating a tendency towards extensive morphological conservatism. We present a biogeographic reconstruction of the colonization of Sundaland and nearby islands which, together with our temporal framework, suggests that lineage diversification centered on the landmasses of the northern Sunda Shelf. This remarkably genetically structured group of amphibians could represent an exceptional case for future studies of geographical structure and diversification in a widespread anuran clade spanning some of the most pronounced geographical barriers on the planet (e.g., Wallace's Line). Studies considering gene flow, morphology, ecological and bioacoustic data are needed to answer these questions and to test whether observed diversity of Puddle frog lineages warrants taxonomic recognition.


Assuntos
Anuros , Biodiversidade , Animais , Anuros/genética , Teorema de Bayes , Filogenia , Filogeografia , RNA Ribossômico 16S/genética , Especificidade da Espécie
6.
Zootaxa ; 3835(1): 59-79, 2014 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-25081435

RESUMO

The megophryid frogs Leptobrachella brevicrus, Leptolalax dringi and Megophrys dringi are species exclusively known  from highly localised areas in isolated mountain ranges on Borneo. The tadpoles and adults in this study were collected at the shared type locality for the three species in Gunung Mulu National Park, Sarawak, Malaysia (Borneo). The species identities of larvae were determined via comparison to syntopic adults using DNA barcoding techniques based on partial 16S rRNA mitochondrial gene sequences. The genetic data supported the status of the three taxa as valid species. Descriptions of colouration in life and after preservation, external morphological features, morphometric measurements and ecological notes in comparison to congeneric species are supplied. The tadpoles of L. brevicrus and L. dringi show similar adaptations to a fossorial lifestyle. These include an elongated, vermiform body, a relatively long tail and small eyes. Both were found in the gravel beds of a small mountain stream. In contrast, the larvae of M. dringi are adapted to occupying and feeding at the surface of pools within the stream. 


Assuntos
Anuros/crescimento & desenvolvimento , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Anuros/anatomia & histologia , Anuros/classificação , Anuros/genética , Tamanho Corporal , Feminino , Larva/anatomia & histologia , Larva/classificação , Larva/genética , Larva/crescimento & desenvolvimento , Malásia , Masculino , Dados de Sequência Molecular , Tamanho do Órgão , Filogenia , RNA Ribossômico 16S/genética
7.
Ecol Evol ; 4(14): 2867-83, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25165525

RESUMO

Specialization to nectarivory is associated with radiations within different bird groups, including parrots. One of them, the Australasian lories, were shown to be unexpectedly species rich. Their shift to nectarivory may have created an ecological opportunity promoting species proliferation. Several morphological specializations of the feeding tract to nectarivory have been described for parrots. However, they have never been assessed in a quantitative framework considering phylogenetic nonindependence. Using a phylogenetic comparative approach with broad taxon sampling and 15 continuous characters of the digestive tract, we demonstrate that nectarivorous parrots differ in several traits from the remaining parrots. These trait-changes indicate phenotype-environment correlations and parallel evolution, and may reflect adaptations to feed effectively on nectar. Moreover, the diet shift was associated with significant trait shifts at the base of the radiation of the lories, as shown by an alternative statistical approach. Their diet shift might be considered as an evolutionary key innovation which promoted significant non-adaptive lineage diversification through allopatric partitioning of the same new niche. The lack of increased rates of cladogenesis in other nectarivorous parrots indicates that evolutionary innovations need not be associated one-to-one with diversification events.

8.
Zootaxa ; (3814): 419-31, 2014 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-24943439

RESUMO

A new species of stream toad of the genus Ansonia is described from Gunung Murud, Pulong Tau National Park, of northern Sarawak, Malaysia, Borneo. Ansonia vidua, sp. nov., is morphologically distinguished from its Bornean congeners by the following combination of characters: medium size (SVL of adult females 33.5-34.4 mm); body uniformly black-brown in life; absence of a visible pattern on dorsum or limbs; presence of two low interorbital ridges; shagreened skin on dorsum, sides and upper surfaces of the limbs with numerous homogeneously small, rounded warts; first finger shorter than second; reduced webbing between the toes and an absence of a sharp tarsal ridge. Uncorrected genetic distances between related taxa of > 4.3% in 16S rRNA gene support its status as a hitherto undescribed species.


Assuntos
Bufonidae/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Animais , Bufonidae/anatomia & histologia , Bufonidae/genética , Ecossistema , Feminino , Malásia , Masculino , Dados de Sequência Molecular , Filogenia
9.
Zootaxa ; 3785: 550-60, 2014 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-24872245

RESUMO

A new brightly-coloured (olive and red) species of microhylid frog of the genus Calluella Stoliczka 1872 is described from the upper elevations of Gunung Penrissen and the Matang Range, Sarawak, East Malaysia (Borneo). Calluella capsa, new species, is diagnosable in showing the following combination of characters: SVL up to 36.0 mm; dorsum weakly granular; a faint dermal fold across forehead; toe tips obtuse; webbing on toes basal; lateral fringes on toes present; outer metatarsal tubercle present; and dorsum greyish-olive, with red spots; half of venter bright red, the rest with large white and dark areas. The new species is the eighth species of Calluella to be described, and the fourth known from Borneo. A preliminary phylogeny of Calluella and its relatives is presented, and the new taxon compared with congeners from Malaysia and other parts of south-east Asia. 


Assuntos
Anuros/anatomia & histologia , Anuros/classificação , Animais , Anuros/genética , Demografia , Malásia , Masculino , Filogenia , Especificidade da Espécie
10.
Mol Phylogenet Evol ; 68(3): 567-81, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23578599

RESUMO

The tree-frog family Rhacophoridae is a major group contributing to the high pecies richness and reproductive diversity among vertebrates of Sundaland. Nonetheless, rhacophorid evolution, specially on Borneo, has not been studied within a phylogenetic context. In this study, we examine the phylogenetic relationships of 38 (out of 41) Bornean species of Rhacophoridae, in combination with data from previous phylogenetic studies. In the final super matrix of 91 species, we analyse sequence data from two mitochondrial and three nuclear genes. The resulting trees show the genus Rhacophorus as a paraphyletic assemblage. As a consequence, we transfer Rhacophorus appendiculatus and R. kajau to two other genera and propose the new phylogeny-based combinations--Kurixalus appendiculatus and Feihyla kajau, respectively. Furthermore, we use our phylogenetic hypotheses to reconstruct the evolution of reproductive modes in rhacophorid tree frogs. Direct development to the exclusion of a free larval stage evolved twice independently, once in an ancestor of the Pseudophilautus+Raorchestes clade in India and Sri Lanka, and once within Philautus in Southeast Asia. The deposition of egg clutches covered by a layer of jelly in Feihyla is also present in F. kajau and thus confirms our generic reassignment. The remarkably high diversity of rhacophorid tree frogs on Borneo is the outcome of a complex pattern of repeated vicariance and dispersal events caused by past changes in the climatic and geological history of the Sunda shelf. We identified geographic clades of closely related endemic species within Rhacophorus and Philautus, which result from local island radiations on Borneo.


Assuntos
Anuros/classificação , Anuros/genética , Biodiversidade , Evolução Biológica , Animais , Sudeste Asiático , DNA Mitocondrial/genética , Evolução Molecular , Filogenia
11.
Mol Phylogenet Evol ; 54(3): 984-94, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19699808

RESUMO

Vicariance is thought to have played a major role in the evolution of modern parrots. However, as the relationships especially of the African taxa remained mostly unresolved, it has been difficult to draw firm conclusions about the roles of dispersal and vicariance. Our analyses using the broadest taxon sampling of old world parrots ever based on 3219bp of three nuclear genes revealed well-resolved and congruent phylogenetic hypotheses. Agapornis of Africa and Madagascar was found to be the sister group to Loriculus of Australasia and Indo-Malayasia and together they clustered with the Australasian Loriinae, Cyclopsittacini and Melopsittacus. Poicephalus and Psittacus from mainland Africa formed the sister group of the Neotropical Arini and Coracopsis from Madagascar and adjacent islands may be the closest relative of Psittrichas from New Guinea. These biogeographic relationships are best explained by independent colonization of the African continent via trans-oceanic dispersal from Australasia and Antarctica in the Paleogene following what may have been vicariance events in the late Cretaceous and/or early Paleogene. Our data support a taxon pulse model for the diversification of parrots whereby trans-oceanic dispersal played a more important role than previously thought and was the prerequisite for range expansion into new continents.


Assuntos
Evolução Molecular , Especiação Genética , Modelos Genéticos , Papagaios/classificação , Filogenia , Animais , Teorema de Bayes , Núcleo Celular/genética , Geografia , Papagaios/genética , Análise de Sequência de DNA
12.
J Morphol ; 270(9): 1095-106, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19388080

RESUMO

The medaka, Oryzias latipes, is a model organism in experimental biology. Its ontogeny and osteology have been studied frequently, but no detailed description of its cranial anatomy exists. Based on manual dissections, histological slide sections, and 3D-reconstructions, we describe the anatomy of the jaw apparatus of O. latipes, focusing on musculature, connective tissue elements, and the nervous system. The soft tissue anatomy of the head of O. latipes is characterized by several derived characters that seem to be related to the modification of the upper jaw and a reduced mobility of its bones, which is an evolutionary novelty of the Beloniformes. These apomorphies could also be influenced by the small size of O. latipes. The maxilla is medial to the premaxilla. The presence of extensive connective tissue elements severely limits the mobility of both bones against each other and against the neurocranium. The external section of m. adductor mandibulae is partly fused with the internal section, originates from the quadrate, and inserts to the lower jaw. The intermediate head of the internal section is narrow and forms a bend along the ventral margin of the orbit. The intramandibular section is a separate narrow muscle between retroarcticular and dentary. These characters need to be verified in other representatives of Beloniformes to test their contribution to the disputed phylogenetic relationships within this taxon and to improve the understanding of the evolution of beak-like jaws in beloniform fishes.


Assuntos
Maxila/anatomia & histologia , Oryzias/anatomia & histologia , Palato Duro/anatomia & histologia , Animais , Evolução Biológica , Cabeça/anatomia & histologia , Cabeça/fisiologia , Maxila/fisiologia , Músculos/fisiologia , Sistema Nervoso/anatomia & histologia , Oryzias/classificação , Oryzias/fisiologia , Palato Duro/fisiologia , Filogenia
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