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1.
Viruses ; 14(2)2022 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-35215906

RESUMO

To date, six hantavirus species have been detected in moles (family Talpidae). In this report, we describe Academ virus (ACDV), a novel hantavirus harbored by the Siberian mole (Talpa altaica) in Western Siberia. Genetic analysis of the complete S-, M-, and partial L-genomic segments showed that ACDV shared a common evolutionary origin with Bruges virus, previously identified in the European mole (Talpa europaea), and is distantly related to other mole-borne hantaviruses. Co-evolution and local adaptation of genetic variants of hantaviruses and their hosts, with possible reassortment events, might have shaped the evolutionary history of ACDV.


Assuntos
Toupeiras/virologia , Orthohantavírus/genética , Orthohantavírus/isolamento & purificação , Animais , Evolução Molecular , Genoma Viral , Orthohantavírus/classificação , Orthohantavírus/fisiologia , Especificidade de Hospedeiro , Toupeiras/classificação , Filogenia , Federação Russa
2.
Zool Res ; 42(3): 294-299, 2021 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-33929104

RESUMO

During a terrestrial vertebrate survey of the Dabie Mountains in Anhui Province, eastern China, we collected four Asian shrew mole specimens (hereafter, shrew moles). Based on published literature and comparison with previously collected materials, the four specimens were similar to shrew moles from the mountains of Southwest China; however, no species in this group has been previously recorded from the Dabie Mountains. The genetic and morphological characteristics of the specimens were analyzed, based upon which a new species of shrew mole is described, named Uropsilus dabieshanensis sp. nov.


Assuntos
Toupeiras/classificação , Animais , China , Toupeiras/genética , Especificidade da Espécie
3.
Sci Rep ; 11(1): 1011, 2021 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-33441654

RESUMO

Afrotheria is a clade of African-origin species with striking dissimilarities in appearance and habitat. In this study, we compared whole proteome sequences of six Afrotherian species to obtain a broad viewpoint of their underlying molecular make-up, to recognize potentially unique proteomic signatures. We find that 62% of the proteomes studied here, predominantly involved in metabolism, are orthologous, while the number of homologous proteins between individual species is as high as 99.5%. Further, we find that among Afrotheria, L. africana has several orphan proteins with 112 proteins showing < 30% sequence identity with their homologues. Rigorous sequence searches and complementary approaches were employed to annotate 156 uncharacterized protein sequences and 28 species-specific proteins. For 122 proteins we predicted potential functional roles, 43 of which we associated with protein- and nucleic-acid binding roles. Further, we analysed domain content and variations in their combinations within Afrotheria and identified 141 unique functional domain architectures, highlighting proteins with potential for specialized functions. Finally, we discuss the potential relevance of highly represented protein families such as MAGE-B2, olfactory receptor and ribosomal proteins in L. africana and E. edwardii, respectively. Taken together, our study reports the first comparative study of the Afrotherian proteomes and highlights salient molecular features.


Assuntos
Eutérios/classificação , Eutérios/genética , Animais , Sequência Conservada , Bases de Dados de Proteínas , Elefantes/classificação , Elefantes/genética , Elefantes/metabolismo , Eutérios/metabolismo , Evolução Molecular , Ouriços/classificação , Ouriços/genética , Ouriços/metabolismo , Anotação de Sequência Molecular , Toupeiras/classificação , Toupeiras/genética , Toupeiras/metabolismo , Filogenia , Domínios Proteicos , Proteínas/química , Proteínas/genética , Proteínas/metabolismo , Proteoma/genética , Proteômica , Musaranhos/classificação , Musaranhos/genética , Musaranhos/metabolismo , Especificidade da Espécie , Trichechus manatus/classificação , Trichechus manatus/genética , Trichechus manatus/metabolismo
4.
Anat Rec (Hoboken) ; 303(1): 65-76, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-30614659

RESUMO

Here I review, compare, and contrast the neurobiology and behavior of the common, eastern mole (Scalopus aquaticus) and the star-nosed mole (Condylura cristata). These two species are part of the same family (Talpidae) and have similar body size and general morphology. But they differ in sensory specializations, complexity of neocortical organization, and behavior. The star-nosed mole has an elaborate mechanosensory organ-the star-consisting of 22 epidermal appendages (rays) covered with 25,000 touch domes called Eimer's organs. This densely innervated structure is represented in the neocortex in three different somatosensory maps, each visible in flattened neocortical sections as a series of 11 modules representing the 11 rays from the contralateral body. The 11th ray is greatly magnified in primary somatosensory cortex (S1). Behavioral studies show the star is moved in a saccadic manner and the 11th ray is a high-resolution tactile fovea, allowing star-nosed moles to forage on small prey with unprecedented speed and efficiency. In contrast, common mole noses lack Eimer's organs, their neocortex contains only two cortical maps of the nose, and they cannot localize small prey. Yet common moles have exceptional olfactory abilities, sniffing in stereo to rapidly localize discrete odor sources originating from larger prey. In addition, common moles are shown to track odorant trails laid down by moving prey. These results highlight the surprising abilities of species once thought to be simple, and the usefulness of diverse species in revealing general principles of brain organization and behavior. Anat Rec, 2019. © 2019 American Association for Anatomy.


Assuntos
Mecanorreceptores/fisiologia , Toupeiras/fisiologia , Órgãos dos Sentidos/fisiologia , Olfato/fisiologia , Tato/fisiologia , Animais , Comportamento Animal , Mapeamento Encefálico , Toupeiras/anatomia & histologia , Toupeiras/classificação , Percepção do Tato
5.
Mol Phylogenet Evol ; 143: 106667, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31676418

RESUMO

Golden moles (Family Chrysochloridae) are small subterranean mammals, endemic to sub-Saharan Africa, and many of the 21 species are listed as threatened on the IUCN Red List. Most species have highly restricted ranges; however two species, the Hottentot golden mole (Amblysomus hottentotus) and the Cape golden mole (Chrysochloris asiatica) have relatively wide ranges. We recently uncovered cryptic diversity within A. hottentotus, through a phylogeographic analysis of this taxon using two mitochondrial gene regions and a nuclear intron. To further investigate this cryptic diversity, we generated nuclear SNP data from across the genome of A. hottentotus, by means of double-digest restriction-site associated DNA sequencing (ddRADSeq), and mapped reads to the Cape golden mole genome. We conducted a phylogenetic analysis and investigated population differentiation. Our results support the distinctiveness of A. h. meesteri. Furthermore, we provide evidence from nuclear SNPs in support of our previous finding that Central coastal samples represent a unique cryptic lineage that is highly divergent from A. h. pondoliae farther south. Although mtDNA suggests that Umtata may represent a unique lineage sister to A. h. longiceps, mito-nuclear discordance from our RADseq data indicate that these samples may instead be closer to A. h. pondoliae, and therefore may not represent a distinct lineage. We stress the importance of recognizing that understudied populations, such as that of Umtata, may represent populations or ESUs under threat and in need of conservation attention. We present a high-quality filtered SNP dataset, comprising thousands of SNPs, which may serve as a useful resource for future golden mole studies. We have thus added to the growing body of research demonstrating the power and utility of RADseq to investigate population differentiation.


Assuntos
Eutérios/classificação , Toupeiras/classificação , Animais , DNA Mitocondrial , Eutérios/genética , Toupeiras/genética , Filogenia , Filogeografia , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA , África do Sul
6.
BMC Evol Biol ; 19(1): 179, 2019 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-31510915

RESUMO

BACKGROUND: Understanding the mechanisms promoting or constraining morphological diversification within clades is a central topic in evolutionary biology. Ecological transitions are of particular interest because of their influence upon the selective forces and factors involved in phenotypic evolution. Here we focused on the humerus and mandibles of talpid moles to test whether the transition to the subterranean lifestyle impacted morphological disparity and phenotypic traits covariation between these two structures. RESULTS: Our results indicate non-subterranean species occupy a significantly larger portion of the talpid moles morphospace. However, there is no difference between subterranean and non-subterranean moles in terms of the strength and direction of phenotypic integration. CONCLUSIONS: Our study shows that the transition to a subterranean lifestyle significantly reduced morphological variability in talpid moles. However, this reduced disparity was not accompanied by changes in the pattern of traits covariation between the humerus and the mandible, suggesting the presence of strong phylogenetic conservatism within this pattern.


Assuntos
Ecossistema , Toupeiras/anatomia & histologia , Pontos de Referência Anatômicos , Animais , Úmero/anatomia & histologia , Análise dos Mínimos Quadrados , Estilo de Vida , Mandíbula/anatomia & histologia , Toupeiras/classificação , Fenótipo , Filogenia , Análise de Componente Principal , Característica Quantitativa Herdável
7.
Curr Biol ; 29(17): R825-R828, 2019 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-31505178

RESUMO

Many people are familiar with the meandering tunnels of moles, far fewer are familiar with the creatures that made them. Such secrecy is, of course, one of the great benefits of burrowing through the earth where few predators can follow. But it's not the only benefit. Soil contains a smorgasbord of nutritious invertebrate prey - hence all the tunneling. In fact the richness of the soil niche has given rise to a diversity of mole species that could be said to resemble the evolutionary diversification of bats, though on a smaller scale. In both cases, mammals have evolved a suite of unique anatomical traits (coincidentally involving modification of the forelimb) that allows them to exploit a huge resource of invertebrate prey that is largely inaccessible to their competitors. For bats the thin, delicate wings were the key innovation, for moles the forelimbs have undergone a similarly dramatic structural shift, but in the opposite direction - the bones have become short, stout, and powerful to act as shovels.


Assuntos
Adaptação Biológica , Características de História de Vida , Toupeiras , Percepção do Tato , Tato , Animais , Toupeiras/anatomia & histologia , Toupeiras/classificação , Toupeiras/fisiologia , Solo
8.
Mol Ecol Resour ; 19(2): 310-326, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30457216

RESUMO

Analysing the impact of anthropogenic and natural river barriers on the dispersal of aquatic and semi-aquatic species may be critical for their conservation. Knowledge of kinship relationships between individuals and reconstructions of pedigrees obtained using genomic data can be extremely useful, not only for studying the social organization of animals, but also inferring contemporary dispersal and quantifying the effect of specific barriers on current connectivity. In this study, we used kinship data to analyse connectivity patterns in a small semi-aquatic mammal, the Pyrenean desman (Galemys pyrenaicus), in an area comprising two river systems with close headwaters and dams of various heights and types. Using a large SNP dataset from 70 specimens, we obtained kinship categories and reconstructed pedigrees. To quantify the barrier effect of specific obstacles, we built kinship networks and devised a method based on the assortativity coefficient, which measures the proportion between observed and expected kinship relationships across a barrier. The estimation of this parameter enabled us to infer that the most important barrier in the area was the watershed divide between the rivers, followed by a dam on one of the rivers. Other barriers did not significantly reduce the expected number of kinship relationships across them. This strategy and the information obtained with it may be crucial in determining the most important connectivity problems in an area and help develop conservation plans aimed at improving genetic exchange between populations of threatened species.


Assuntos
Distribuição Animal , Genética Populacional , Toupeiras/classificação , Toupeiras/genética , Animais , Genótipo , Filogenia , Polimorfismo de Nucleotídeo Único , Rios
9.
PLoS One ; 10(12): e0144995, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26683828

RESUMO

The Greater Maputaland-Pondoland-Albany (GMPA) region of southern Africa was recently designated as a centre of vertebrate endemism. The phylogeography of the vertebrate taxa occupying this region may provide insights into the evolution of faunal endemism in south-eastern Africa. Here we investigate the phylogeographic patterns of an understudied small mammal species assemblage (Amblysomus) endemic to the GMPA, to test for cryptic diversity within the genus, and to better understand diversification across the region. We sampled specimens from 50 sites across the distributional range of Amblysomus, with emphasis on the widespread A. hottentotus, to analyse geographic patterns of genetic diversity using mitochondrial DNA (mtDNA) and nuclear intron data. Molecular dating was used to elucidate the evolutionary and phylogeographic history of Amblysomus. Our phylogenetic reconstructions show that A. hottentotus comprises several distinct lineages, or evolutionarily significant units (ESUs), some with restricted geographic ranges and thus worthy of conservation attention. Divergence of the major lineages dated to the early Pliocene, with later radiations in the GMPA during the late-Pliocene to early-Pleistocene. Evolutionary diversification within Amblysomus may have been driven by uplift of the Great Escarpment c. 5-3 million years ago (Ma), habitat changes associated with intensification of the east-west rainfall gradient across South Africa and the influence of subsequent global climatic cycles. These drivers possibly facilitated geographic spread of ancestral lineages, local adaptation and vicariant isolation. Our study adds to growing empirical evidence identifying East and southern Africa as cradles of vertebrate diversity.


Assuntos
DNA Mitocondrial/análise , Mitocôndrias/genética , Toupeiras/classificação , Toupeiras/genética , África Oriental , África Austral , Animais , Evolução Biológica , Variação Genética , Dados de Sequência Molecular , Filogenia , Filogeografia
10.
Dokl Biol Sci ; 464: 230-4, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26530064

RESUMO

The results of the first molecular study focused on the phylogenetic position of the Gansu mole, Scapanulus oweni are presented. The analysis based on sequences of the mitochondrial cytb gene and five nuclear genes supports the monophyly of the Scalopini tribe including S. oweni and shows that two highly fossorial talpid tribes, Talpini and Scalopini, are not immediate sister taxa. These results highlight the role of morphological parallelism as a potential source of conflict between molecular and morphology-based phylogenies in Talpidae.


Assuntos
Toupeiras/genética , Filogenia , Animais , Grupo dos Citocromos b/genética , Toupeiras/classificação
11.
Virus Res ; 187: 15-21, 2014 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-24509342

RESUMO

Hantaviruses are among the most important zoonotic pathogens of humans, causing either hemorrhagic fever with renal syndrome (HFRS) or hantavirus pulmonary syndrome (HPS). From the period 1964-2006 almost all hantaviruses had been identified in rodents, with the exception of Thottapalayam virus (TPMV) isolated from shrews sampled in India. As a consequence, rodents were considered as the natural reservoir hosts. However, over the past seven years, most of the newly found hantavirus genotypes have been from either shrews or moles. Remarkably, in recent years divergent hantaviruses have also been identified in bats sampled from both Africa and Asia. All these data indicate that hantaviruses have a broad range of natural reservoir hosts. Phylogenetic analyses of the available sequences of hantaviruses suggest that hantaviruses might have first appeared in Chiroptera (bats) or Soricomorpha (moles and shrews), before emerging in rodent species. Although rodent hantaviruses cluster according to whether their hosts are members of the Murinae and Cricetidae, the phylogenetic histories of the viruses are not always congruent with those of their hosts, indicating that cross-species transmission events have occurred at all taxonomic levels. In sum, both cross-species transmission and co-divergence have produced the high genetic diversity of hantaviruses described to date.


Assuntos
Infecções por Hantavirus/transmissão , Infecções por Hantavirus/veterinária , Orthohantavírus/genética , Filogenia , África , Animais , Ásia , Evolução Biológica , Quirópteros/classificação , Quirópteros/virologia , Variação Genética , Orthohantavírus/classificação , Infecções por Hantavirus/virologia , Especificidade de Hospedeiro , Interações Hospedeiro-Patógeno , Toupeiras/classificação , Toupeiras/virologia , Musaranhos/classificação , Musaranhos/virologia
12.
Mol Phylogenet Evol ; 70: 513-21, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24140029

RESUMO

The tribe Talpini is a group of strictly subterranean moles distributed across the Eurasian Continent whose phylogenetic relationships and taxonomy remain unresolved. Here we report a multi-locus nuclear-mitochondrial DNA dataset (9468 bp) from 11 talpine species encompassing all five recognized genera, together with analyses of their divergence times and evolutionary affinities inferred from maximum likelihood and Bayesian approaches. Our results finely resolved all relationships except the root of the four recognized Asian genera, which was placed sister to the genus Talpa. With respect to the Asian clade, we moreover provide the first molecular support for a sister-taxon relationship between Parascaptor and Scaptochirus and confirm that the genus Euroscaptor is paraphyletic. Further, and despite a relatively small sample size (22 specimens), our species delimitation analyses support the existence of at least two genetically distinct, and hence potentially cryptic species. Taken together, these findings argue that generic status should be given to E. mizura and illustrate that the taxonomic diversity of the tribe Talpini in mountainous regions of southwestern China and Southeast Asia is underestimated. Finally, results of our divergence time analyses support a rapid radiation of the endemic Asian genera in the late-Miocene, which temporally corresponds with enhanced aridity and cooling arising from a significant uplift of the Himalayan-Tibetan plateau.


Assuntos
Toupeiras/genética , Filogenia , Animais , Teorema de Bayes , DNA Mitocondrial/genética , Toupeiras/classificação , Análise de Sequência de DNA
13.
BMC Evol Biol ; 13: 232, 2013 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-24161152

RESUMO

BACKGROUND: The genus Uropsilus comprises a group of terrestrial, montane mammals endemic to the Hengduan and adjacent mountains. These animals are the most primitive living talpids. The taxonomy has been primarily based on cursory morphological comparisons and the evolutionary affinities are little known. To provide insight into the systematics of this group, we estimated the first multi-locus phylogeny and conducted species delimitation, including taxon sampling throughout their distribution range. RESULTS: We obtained two mitochondrial genes (~1, 985 bp) and eight nuclear genes (~4, 345 bp) from 56 specimens. Ten distinct evolutionary lineages were recovered from the three recognized species, eight of which were recognized as species/putative species. Five of these putative species were found to be masquerading as the gracile shrew mole. The divergence time estimation results indicated that climate change since the last Miocene and the uplift of the Himalayas may have resulted in the diversification and speciation of Uropsilus. CONCLUSIONS: The cryptic diversity found in this study indicated that the number of species is strongly underestimated under the current taxonomy. Two synonyms of gracilis (atronates and nivatus) should be given full species status, and the taxonomic status of another three potential species should be evaluated using extensive taxon sampling, comprehensive morphological, and morphometric approaches. Consequently, the conservation status of Uropsilus spp. should also be re-evaluated, as most of the species/potential species have very limited distribution.


Assuntos
Toupeiras/classificação , Toupeiras/genética , Filogenia , Animais , Evolução Biológica , Núcleo Celular/genética , China , DNA Mitocondrial/genética , Genética Populacional
15.
BMC Evol Biol ; 13: 55, 2013 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-23442022

RESUMO

BACKGROUND: Talpids include forms with different degree of fossoriality, with major specializations in the humerus in the case of the fully fossorial moles. We studied the humeral microanatomy of eleven extant and eight extinct talpid taxa of different lifestyles and of two non-fossorial outgroups and examined the effects of size and phylogeny. We tested the hypothesis that bone microanatomy is different in highly derived humeri of fossorial taxa than in terrestrial and semi-aquatic ones, likely due to special mechanical strains to which they are exposed to during digging. This study is the first comprehensive examination of histological parameters in an ecologically diverse and small-sized mammalian clade. RESULTS: No pattern of global bone compactness was found in the humeri of talpids that could be related to biomechanical specialization, phylogeny or size. The transition zone from the medullary cavity to the cortical compacta was larger and the ellipse ratio smaller in fossorial talpids than in non-fossorial talpids. No differences were detected between the two distantly related fossorial clades, Talpini and Scalopini. CONCLUSIONS: At this small size, the overall morphology of the humerus plays a predominant role in absorbing the load, and microanatomical features such as an increase in bone compactness are less important, perhaps due to insufficient gravitational effects. The ellipse ratio of bone compactness shows relatively high intraspecific variation, and therefore predictions from this ratio based on single specimens are invalid.


Assuntos
Evolução Biológica , Úmero/anatomia & histologia , Toupeiras/anatomia & histologia , Filogenia , Animais , Ecossistema , Extinção Biológica , Fósseis , Toupeiras/classificação , Toupeiras/genética
16.
Mol Ecol ; 19(24): 5432-51, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21059127

RESUMO

Hotspots of intraspecific diversity have been observed in most species, often within areas of putative Pleistocene refugia. They have thus mostly been viewed as the outcome of prolonged stability of large populations within the refugia. However, recent evidence has suggested that several other microevolutionary processes could also be involved in their formation. Here, we investigate the contribution of these processes to current range-wide patterns of genetic diversity in the Italian endemic mole Talpa romana, using both nuclear (30 allozyme loci) and mitochondrial markers (cytochrome b sequences). Southern populations of this species showed an allozyme variation that is amongst the highest observed in small mammals (most populations had an expected heterozygosity of 0.10 or above), which was particularly unexpected for a subterranean species. Population genetic, phylogeographic and historical demographic analyses indicated that T. romana populations repeatedly underwent allopatric differentiations followed by secondary admixture within the refugial range in southern Italy. A prolonged demographic stability was reliably inferred from the mitochondrial DNA data only for a population group located north and east of the Calabrian peninsula, showing comparatively lower levels of allozyme variability, and lacking evidence of secondary admixture with other groups. Thus, our results point to the admixture between differentiated lineages as the main cause of the higher levels of diversity of refugial populations. When compared with the Pleistocene evolutionary history recently inferred for species from both the same and other geographic regions, these results suggest the need for a reappraisal of the role of gene exchange in the formation of intraspecific hotspots of genetic diversity.


Assuntos
Variação Genética/genética , Toupeiras/genética , Animais , Fluxo Gênico/genética , Geografia , Toupeiras/classificação
17.
Zh Obshch Biol ; 71(3): 244-55, 2010.
Artigo em Russo | MEDLINE | ID: mdl-20583635

RESUMO

The goal of the investigation was to clarify the ways of subcutaneous muscles development in burrowing forms of insectivores--moles (Talpidae) and golden moles (Chrysochloridae). To achieve the goal the comparative morpho-functional analysis of subcutaneous and facial musculature of six mole genera (Neurotrichus, Urotrichus, Talpa, Mogera, Scalopus, Parascalops), two genera of chrysochlorids (Chrysochloris, Eremitalpa), and some other non-specialized forms of insectivorous mammals from Erinaceidae, Tenrecidae, Soricidae and Solenodontidae was carried out. It was shown that some of m. cutaneus trunci derivatives interact intimately with facial musculature. Besides, subcutaneous muscle forms additional layers that facilitate the operation of shaking ground particles off the for, which is rather important for burrowers. Overall complication of subcutaneous musculature in moles and chrysochlorids is accompanied by convergent similarity in the development of some musculature portions. At the same time some layers of m. cutaneus trunci seem to have evolved in different, special ways.


Assuntos
Toupeiras/anatomia & histologia , Toupeiras/crescimento & desenvolvimento , Desenvolvimento Muscular/fisiologia , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/crescimento & desenvolvimento , Animais , Biodiversidade , Evolução Biológica , Músculos Faciais/anatomia & histologia , Músculos Faciais/crescimento & desenvolvimento , Músculos Faciais/fisiologia , Toupeiras/classificação , Toupeiras/fisiologia , Músculo Esquelético/fisiologia , Especificidade da Espécie
18.
BMC Evol Biol ; 10: 69, 2010 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-20214773

RESUMO

BACKGROUND: Golden moles (Chrysochloridae) are small, subterranean, afrotherian mammals from South Africa and neighboring regions. Of the 21 species now recognized, some (e.g., Chrysochloris asiatica, Amblysomus hottentotus) are relatively common, whereas others (e.g., species of Chrysospalax, Cryptochloris, Neamblysomus) are rare and endangered. Here, we use a combined analysis of partial sequences of the nuclear GHR gene and morphological characters to derive a phylogeny of species in the family Chrysochloridae. RESULTS: Although not all nodes of the combined analysis have high support values, the overall pattern of relationships obtained from different methods of phylogeny reconstruction allow us to make several recommendations regarding the current taxonomy of golden moles. We elevate Huetia to generic status to include the species leucorhinus and confirm the use of the Linnean binomial Carpitalpa arendsi, which belongs within Amblysominae along with Amblysomus and Neamblysomus. A second group, Chrysochlorinae, includes Chrysochloris, Cryptochloris, Huetia, Eremitalpa, Chrysospalax, and Calcochloris. Bayesian methods make chrysochlorines paraphyletic by placing the root within them, coinciding with root positions favored by a majority of randomly-generated outgroup taxa. Maximum Parsimony (MP) places the root either between chrysochlorines and amblysomines (with Chlorotalpa as sister taxon to amblysomines), or at Chlorotalpa, with the former two groups reconstructed as monophyletic in all optimal MP trees. CONCLUSIONS: The inclusion of additional genetic loci for this clade is important to confirm our taxonomic results and resolve the chrysochlorid root. Nevertheless, our optimal topologies support a division of chrysochlorids into amblysomines and chrysochlorines, with Chlorotalpa intermediate between the two. Furthermore, evolution of the chrysochlorid malleus exhibits homoplasy. The elongate malleus has evolved just once in the Cryptochloris-Chrysochloris group; other changes in shape have occurred at multiple nodes, regardless of how the root is resolved.


Assuntos
Evolução Molecular , Toupeiras/genética , Filogenia , Animais , Teorema de Bayes , Toupeiras/anatomia & histologia , Toupeiras/classificação , Análise de Sequência de DNA
19.
Mol Phylogenet Evol ; 55(2): 372-80, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20138223

RESUMO

The range of the genus Talpa covers almost all Europe up to Western Asia. This genus has never been the object of comprehensive systematic studies using molecular and genetic techniques, such that the evolutionary relationships among species remain unclear. Talpa shows high levels of endemism, and the influence of past glaciation cycles on the distribution pattern of several species has been hypothesized. In this work, we assessed the molecular systematics of the genus using the mitochondrial gene cytochrome b from eight of the nine extant species of Talpa moles. Furthermore, molecular clock estimations were used to hypothesize a biogeographic scenario in concordance with fossil data. Results suggest a monophyletic origin of the genus and a common ancestor for the western European moles T. europaea, T. caeca, T. romana and T. occidentalis. The eastern species T. altaica and T. caucasica are basally divergent. The estimated ages of divergence among lineages are in accordance with a Miocene origin of the extant moles. The genus likely originated in Asia, spreading into Europe during the Pliocene. The evolution of moles appears to have been driven by changes in moisture levels that influenced extinction and speciation events during the Miocene and the Pliocene. Pleistocene climatic oscillations likely caused the range shrinkages and expansions that led to the current distribution pattern of most Talpa species.


Assuntos
Evolução Molecular , Toupeiras/genética , Filogenia , Animais , Teorema de Bayes , Citocromos b/genética , DNA Mitocondrial/genética , Geografia , Funções Verossimilhança , Modelos Genéticos , Toupeiras/classificação , Análise de Sequência de DNA
20.
Cytogenet Genome Res ; 121(2): 110-9, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18544934

RESUMO

Golden moles (Chrysochloridae) are small, subterranean mammals endemic to sub-Saharan Africa that together with tenrecs constitute one of six orders in Afrotheria. Here we present a comprehensive karyotypic comparison among six species/subspecies of golden moles based on G-banding and chromosome painting. By expanding the species representation to include a further five species recently published in a companion paper, we were able to map the distribution of telomeric repeats in ten species/subspecies that are representative of six of the nine currently recognized genera. We conclude that: (i) the monophyly of Amblysomus is supported by the amplification of heterochromatin in several pericentric regions and one intrachromosomal rearrangement; (ii) A. hottentotus meesteri groups as sister to a clade that contains A. h. hottentotus, A. h. longiceps, A. h. pondoliae and A. robustus, an association that is underpinned by a shared intrachromosomal rearrangement and the detection of telomeric sequences in the centromeres of all chromosomes of the three A. hottentotus subspecies and A. robustus but, importantly, not in those of A. h. meesteri. These findings indicate an absence of gene flow suggesting that A. h. meesteri should be elevated to specific status. We hypothesize that the lack of gene flow may, in part, reflect hybrid dysgenesis resulting from abnormal meiotic segregation as a consequence of differences in the nature of the centromeric specific satellites; (iii) chromosomes 7 and 13 of Chrysochloris asiatica are fused in both Calcochloris obtusirostris and Eremitalpa granti, but that the position of the centromere in the fused chromosome differs in each species. This suggests that rather than being indicative of common ancestry, the fusion is more likely a convergent character which has arisen independently in each lineage. Furthermore our painting data show two centromeric shifts that are probably autapomorphic for C. obtusirostris. Finally, we conclude that (iv) golden moles are characterized by strong karyotypic conservatism but in marked contrast to the constrained rates of change exhibited by most species, A. robustus is unique in that three autapomorphic fissions define its evolutionary history, and hence the more extensive reshuffling of its genome.


Assuntos
Toupeiras/genética , Animais , Sequência de Bases , Bandeamento Cromossômico , Cromossomos/genética , Citogenética , Primers do DNA/genética , Evolução Molecular , Fluxo Gênico , Hibridização in Situ Fluorescente , Cariotipagem , Toupeiras/classificação , Filogenia , Sequências Repetitivas de Ácido Nucleico , Especificidade da Espécie , Telômero/genética
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