RESUMO
Pteropodidae and Hipposideridae are 2 of the 9 chiropteran families that occur on Madagascar. Despite major advancements in the systematic study of the island's bat fauna, few karyotypic data exist for endemic species. We utilized G- and C-banding in combination with chromosome painting with Myotismyotis probes to establish a genome-wide homology among Malagasy species belonging to the families Pteropodidae (Pteropus rufus 2n = 38; Rousettus madagascariensis, 2n = 36), Hipposideridae (Hipposideros commersoni s.s., 2n = 52), and a single South African representative of the Rhinolophidae (Rhinolophus clivosus, 2n = 58). Painting probes of M. myotis detected 26, 28, 28, and 29 regions of homology in R. madagascariensis, P. rufus, H. commersoni s.s, and R. clivosus, respectively. Translocations, pericentric inversions, and heterochromatin additions were responsible for karyotypic differences amongst the Malagasy pteropodids. Comparative chromosome painting revealed a novel pericentric inversion on P. rufus chromosome 4. Chromosomal characters suggest a close evolutionary relationship between Rousettus and Pteropus. H. commersoni s.s. shared several chromosomal characters with extralimital congeners but did not exhibit 2 chromosomal synapomorphies proposed for Hipposideridae. This study provides further insight into the ancestral karyotypes of pteropodid and hipposiderid bats and corroborates certain molecular phylogenetic hypotheses.
Assuntos
Quirópteros/classificação , Quirópteros/genética , Coloração Cromossômica , Evolução Molecular , Cariótipo , Animais , Bandeamento Cromossômico , Inversão Cromossômica , Cromossomos de Mamíferos/genética , Heterocromatina , Madagáscar , Filogenia , Translocação GenéticaRESUMO
The paucity of data for the molossid bat Otomops throughout its range has hindered our ability to resolve the number of Otomops species present within the Afro-Malagasy region (including the Arabian Peninsula). This paper employed an integrative approach by combining morphometric (cranial morphology) and molecular (mitochondrial cytochrome b and D-loop sequences, nuclear intron sequences and microsatellites) data to identify the number of Otomops taxa occurring in the Afro-Malagasy region. Three taxa were identified, two of which could be assigned to existing species, i.e. O. martiensseni and O. madagascariensis. The third taxon, previously recognised as O. martiensseni (Matschie 1897), is described herein as a new species, Otomops harrisoni sp. nov., and can be differentiated from O. martiensseni s.s. based on both molecular and morphometric data. Locality data of specimens belonging to O. harrisoni suggest that its distribution range extends from the Arabian Peninsula through to Eritrea and south to Ethiopia and Kenya.
Assuntos
Quirópteros/anatomia & histologia , Quirópteros/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Quirópteros/genética , Quirópteros/crescimento & desenvolvimento , Ecossistema , Etiópia , Feminino , Quênia , Masculino , Tamanho do Órgão , FilogeniaRESUMO
BACKGROUND: The Commerson's leaf-nosed bat, Hipposideros commersoni sensu stricto, is endemic to Madagascar and is relatively common in the western portion of the island, where it is found in areas, including forested zones, from sea level to 1325 m. A previous study on morphological patterns of geographic variation within the species highlighted the presence of two distinct morphotypes; larger individuals in the north portion of the island and smaller individuals in the south. The main aim of this study was to use a combination of craniodental morphology and molecular data (mitochondrial and nuclear) to test previous hypotheses based on morphology and clarify the evolutionary history of the species group. METHODS: We sequenced mitochondrial and nuclear genes from Hipposideros commersoni obtained from the western portion of Madagascar, and compared them with other African species as outgroups. We analyzed the sequence data using Maximum Likelihood and Bayesian phylogenetic inference. Divergence dates were estimated using Bayesian molecular clock approach. Variation in craniodental variables was also assessed from sequenced individuals. RESULTS: The molecular analyses suggest that H. commersoni is not monophyletic, with strong support for the presence of several independently evolving lineages. Two individuals amongst those sequenced from Isalo (south central) and Itampolo (southwest) form a separate clade (Clade A), distinct from other H. commersoni, and sister to continental African H. vittatus and H. gigas. Within the H. commersoni clade, the molecular data support two geographically distributed clades; one from the south (Clade B) and the other from the north (Clade C), which diverged approximately 3.38 million years ago. Morphometric data were consistent with the molecular analyses, suggesting a north-south break within H. commersoni. However, at some localities, animals from both clades occurred in sympatry and these individuals could not be differentiated based on external and craniodental measurements. CONCLUSIONS: Using a combination of molecular and morphological characters, this study presents evidence of cryptic diversity in H. commersoni on Madagascar. Further fine-scale phylogeographic studies are needed to fully resolve the systematics of H. commersoni. This study highlights the utility of the combined approach in employing both morphological and molecular data to provide insights into the evolutionary history of Malagasy population currently assigned to H. commersoni.
Assuntos
Quirópteros/classificação , África , Animais , Teorema de Bayes , Quirópteros/anatomia & histologia , Quirópteros/genética , Feminino , Especiação Genética , Madagáscar , Masculino , Filogenia , Análise de Sequência de DNARESUMO
The aim of this study was to identify and determine the genetic diversity of Fasciola species in cattle from Zimbabwe, the KwaZulu-Natal and Mpumalanga provinces of South Africa and selected wildlife hosts from Zimbabwe. This was based on analysis of DNA sequences of the nuclear ribosomal internal transcribed spacer (ITS1 and 2) and mitochondrial cytochrome oxidase 1 (CO1) regions. The sample of 120 flukes was collected from livers of 57 cattle at 4 abattoirs in Zimbabwe and 47 cattle at 6 abattoirs in South Africa; it also included three alcohol-preserved duiker, antelope and eland samples from Zimbabwe. Aligned sequences (ITS 506 base pairs and CO1 381 base pairs) were analyzed by neighbour-joining, maximum parsimony and Bayesian inference methods. Phylogenetic trees revealed the presence of Fasciola gigantica in cattle from Zimbabwe and F. gigantica and Fasciola hepatica in the samples from South Africa. F. hepatica was more prevalent (64%) in South Africa than F. gigantica. In Zimbabwe, F. gigantica was present in 99% of the samples; F. hepatica was found in only one cattle sample, an antelope (Hippotragus niger) and a duiker (Sylvicapra grimmia). This is the first molecular confirmation of the identity Fasciola species in Zimbabwe and South Africa. Knowledge on the identity and distribution of these liver flukes at molecular level will allow disease surveillance and control in the studied areas.
Assuntos
Doenças dos Bovinos/parasitologia , DNA de Helmintos/genética , Fasciola/genética , Fasciolíase/parasitologia , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , DNA Espaçador Ribossômico/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Fasciolíase/epidemiologia , Regulação da Expressão Gênica , Variação Genética , Haplótipos , Filogenia , África do Sul/epidemiologia , Zimbábue/epidemiologiaRESUMO
BACKGROUND: South Africa's long and extensive trade activity has ensured ample opportunities for exotic species introduction. Whereas the rich biodiversity of endemic southern African fauna has been the focus of many studies, invasive vertebrates are generally overlooked despite potential impacts on biodiversity, health and agriculture. Genetic monitoring of commensal rodents in South Africa which uncovered the presence of Rattus tanezumi, a South-East Asian endemic not previously known to occur in Africa, provided the impetus for expanded studies on all invasive Rattus species present. RESULTS: To this end, intensified sampling at 28 South African localities and at one site in Swaziland, identified 149 Rattus specimens. Cytochrome b gene sequencing revealed the presence of two R. tanezumi, seven Rattus rattus and five Rattus norvegicus haplotypes in south Africa. Phylogenetic results were consistent with a single, recent R. tanezumi introduction and indicated that R. norvegicus and R. rattus probably became established following at least two and three independent introductions, respectively. Intra- and inter-specific diversity was highest in informal human settlements, with all three species occurring at a single metropolitan township site. Rattus norvegicus and R. rattus each occurred sympatrically with Rattus tanezumi at one and five sites, respectively. Karyotyping of selected R. rattus and R. tanezumi individuals identified diploid numbers consistent with those reported previously for these cryptic species. Ordination of bioclimatic variables and MaxEnt ecological niche modelling confirmed that the bioclimatic niche occupied by R. tanezumi in south Africa was distinct from that occupied in its naturalised range in south-east Asia suggesting that factors other than climate may influence the distribution of this species. CONCLUSIONS: This study has highlighted the value of genetic typing for detecting cryptic invasive species, providing historical insights into introductions and for directing future sampling. The apparent ease with which a cryptic species can become established signals the need for broader implementation of genetic monitoring programmes. In addition to providing baseline data and potentially identifying high-risk introduction routes, the predictive power of ecological niche modelling is enhanced when species records are genetically verified.
Assuntos
Espécies Introduzidas , Ratos/genética , África Subsaariana , Animais , Biodiversidade , Citocromos b/genética , Filogeografia , Ratos/classificação , África do SulRESUMO
The chiropteran fauna of Madagascar comprises eight of the 19 recognized families of bats, including the endemic Myzopodidae. While recent systematic studies of Malagasy bats have contributed to our understanding of the morphological and genetic diversity of the island's fauna, little is known about their cytosystematics. Here we investigate karyotypic relationships among four species, representing four families of Chiroptera endemic to the Malagasy region using cross-species chromosome painting with painting probes of Myotis myotis: Myzopodidae (Myzopoda aurita, 2n = 26), Molossidae (Mormopterus jugularis, 2n = 48), Miniopteridae (Miniopterus griveaudi, 2n = 46), and Vespertilionidae (Myotis goudoti, 2n = 44). This study represents the first time a member of the family Myzopodidae has been investigated using chromosome painting. Painting probes of M. myotis were used to delimit 29, 24, 23, and 22 homologous chromosomal segments in the genomes of M. aurita, M. jugularis, M. griveaudi, and M. goudoti, respectively. Comparison of GTG-banded homologous chromosomes/chromosomal segments among the four species revealed the genome of M. aurita has been structured through 14 fusions of chromosomes and chromosomal segments of M. myotis chromosomes leading to a karyotype consisting solely of bi-armed chromosomes. In addition, chromosome painting revealed a novel X-autosome translocation in M. aurita. Comparison of our results with published chromosome maps provided further evidence for karyotypic conservatism within the genera Mormopterus, Miniopterus, and Myotis. Mapping of chromosomal rearrangements onto a molecular consensus phylogeny revealed ancestral syntenies shared between Myzopoda and other bat species of the infraorders Pteropodiformes and Vespertilioniformes. Our study provides further evidence for the involvement of Robertsonian (Rb) translocations and fusions/fissions in chromosomal evolution within Chiroptera.
Assuntos
Quirópteros/genética , Coloração Cromossômica , Evolução Molecular , Variação Genética , Cariotipagem , Animais , Feminino , Madagáscar , Masculino , Filogenia , Especificidade da Espécie , Translocação GenéticaRESUMO
Our purpose was to discuss the need for measuring and documenting social work services, as well as to discuss the data and statistical collection method used in Mayo Clinic's Section of Medical Social Services, which may be useful to other social service departments. The lack of empirical data showing the value of social work services may lead to decreases in staffing in medical social work departments. Mayo Clinic uses a computer application called MedSoc to gather case information and measure productivity, which is based on demand and capacity. Through use of MedSoc, our section improved communication among social work staff members and justified an increase in staffing of 38% from late 1997 to 2002.