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1.
Biol Lett ; 13(3)2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28275167

RESUMO

Some primate populations include both trichromatic and dichromatic (red-green colour blind) individuals due to allelic variation at the X-linked opsin locus. This polymorphic trichromacy is well described in day-active New World monkeys. Less is known about colour vision in Malagasy lemurs, but, unlike New World monkeys, only some day-active lemurs are polymorphic, while others are dichromatic. The evolutionary pressures underlying these differences in lemurs are unknown, but aspects of species ecology, including variation in activity pattern, are hypothesized to play a role. Limited data on X-linked opsin variation in lemurs make such hypotheses difficult to evaluate. We provide the first detailed examination of X-linked opsin variation across a lemur clade (Indriidae). We sequenced the X-linked opsin in the most strictly diurnal and largest extant lemur, Indri indri, and nine species of smaller, generally diurnal indriids (Propithecus). Although nocturnal Avahi (sister taxon to Propithecus) lacks a polymorphism, at least eight species of diurnal indriids have two or more X-linked opsin alleles. Four rainforest-living taxa-I. indri and the three largest Propithecus species-have alleles not previously documented in lemurs. Moreover, we identified at least three opsin alleles in Indri with peak spectral sensitivities similar to some New World monkeys.


Assuntos
Visão de Cores/genética , Opsinas/genética , Strepsirhini/genética , Animais , Ecossistema , Genes Ligados ao Cromossomo X , Polimorfismo Genético , Análise de Sequência de Proteína
2.
Am J Primatol ; 78(12): 1316-1325, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27391113

RESUMO

In group-living species with male dominance hierarchies where receptive periods of females do not overlap, high male reproductive skew would be predicted. However, the existence of female multiple mating and alternative male mating strategies can call into question single-male monopolization of paternity in groups. Ring-tailed lemurs (Lemur catta) are seasonally breeding primates that live in multi-male, multi-female groups. Although established groups show male dominance hierarchies, male dominance relationships can break down during mating periods. In addition, females are the dominant sex and mate with multiple males during estrus, including group residents, and extra-group males-posing the question of whether there is high or low male paternity skew in groups. In this study, we analyzed paternity in a population of wild L. catta from the Bezà Mahafaly Special Reserve in southwestern Madagascar. Paternity was determined with 80-95% confidence for 39 offspring born to nine different groups. We calculated male reproductive skew indices for six groups, and our results showed a range of values corresponding to both high and low reproductive skew. Between 21% and 33% of offspring (3 of 14 or three of nine, counting paternity assignments at the 80% or 95% confidence levels, respectively) were sired by extra-troop males. Males siring offspring within the same group during the same year appear to be unrelated. Our study provides evidence of varying male reproductive skew in different L. catta groups. A single male may monopolize paternity across one or more years, while in other groups, >1 male can sire offspring within the same group, even within a single year. Extra-group mating is a viable strategy that can result in extra-group paternity for L. catta males.


Assuntos
Lemur , Paternidade , Comportamento Sexual Animal , Animais , Feminino , Madagáscar , Masculino , Predomínio Social
3.
Folia Primatol (Basel) ; 86(1-2): 66-75, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26022302

RESUMO

Lemur catta has traditionally been considered a species with male-biased dispersal; however, occasional female dispersal occurs. Using molecular data, we evaluated dispersal patterns in 2 L. catta populations in southwestern Madagascar: Tsimanampesotse National Park (TNP) and Bezà Mahafaly Special Reserve (BMSR). We also investigated the genetic differentiation between the populations and dispersal partner relatedness. Results showed minor genetic differentiation between the populations (Ï´(ST) = 0.039), which may indicate gene flow historically occurring in this region, made possible by the presence of L. catta groups between the sites. Different patterns of sex-biased dispersal were found between the sites using corrected assignment indices: male-biased dispersal in TNP, and a lack of sex-biased dispersal in BMSR. Observational evidence of female dispersal in BMSR supports these results and may imply intense female resource competition in and around BMSR, because small groups of 2-3 females have been observed dispersing within BMSR and entering the reserve from outside. These dispersing groups largely consisted of mothers transferring with daughters, although we have an aunt-niece pair transferring together. Genetic data suggest that males also transfer with relatives. Our data demonstrate that dispersal partners consist of same-sexed kin for L. catta males and females, highlighting the importance of kin selection.


Assuntos
Distribuição Animal , Lemur/genética , Animais , Comportamento Competitivo , Feminino , Fluxo Gênico , Lemur/fisiologia , Lemur/psicologia , Madagáscar , Masculino , Repetições de Microssatélites , Fatores Sexuais , Comportamento Social
4.
Zoo Biol ; 34(5): 463-72, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26032097

RESUMO

Genetic variability among captive and wild ring-tailed lemurs (Lemur catta) was assessed using mitochondrial and nuclear DNA data. A 529 bp segment of mtDNA was sequenced and 9 microsatellite loci were genotyped for 286 ring-tailed lemurs. Samples were obtained from the well-studied L. catta population at the Bezà Mahafaly Special Reserve and from captive animals at six institutions worldwide. We found evidence of possible patrilineal contribution but the absence of matrilineal contribution from the Bezà area, and haplotypes not found in Bezà but present in Ambohimahavelona, Andringitra Massif, and other unknown locations, in the sampled captive population, indicating that the founders of the captive population originated from a wide geographic range. Total genetic variation and relatedness in captive L. catta in the six institutions were similar in extent to that of the wild population in Bezà. Based on the diverse origins of the captive population founders our results suggest the erosion of genetic diversity in the captive population. Sampled individuals from the same institution were more closely related to each other than members of a social group in the wild. Individuals housed at different institutions were less closely related than those of different social groups at Bezà, indicating lower genetic exchange between captive institutions than between social groups in a locality in the wild. Our findings underscore the usefulness of genotyping in determining the geographic origin of captive population founders, obtaining pedigree information if paternity is uncertain, and in maximizing preservation of extant genetic diversity in captivity.


Assuntos
Variação Genética , Lemur/genética , Animais , Animais Selvagens , Animais de Zoológico , DNA Mitocondrial/genética , Feminino , Genótipo , Haplótipos , Madagáscar , Masculino , Repetições de Microssatélites , Análise de Sequência de DNA
5.
Zootaxa ; 3620: 112-28, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-26120699

RESUMO

Pseudophilautus stellatus (Kelaart 1853) has been rediscovered from the Peak Wilderness, Central Hills of Sri Lanka. The species, till now known only from its lost holotype, was the first shrub frog described from Sri Lanka, and had not been reported since then. It was thought to have become extinct for nearly 157 years, being the amphibian species "lost" for the longest amount of time. Here we designate a neotype from the material collected at what we consider its type locality, having considered characters of the lost holotype and provide a complete description. We have conducted a molecular phylogenetic analysis, on which basis the species is well differentiated from all other Pseudophilautus sequenced so far, and placed in a clade together with P. femoralis, P. frankenbergi, P. mooreorum, and P. poppiae.


Assuntos
Anuros/classificação , Anuros/genética , Animais , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , RNA Ribossômico/genética , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Sri Lanka
6.
BMC Evol Biol ; 9: 32, 2009 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-19196458

RESUMO

BACKGROUND: Hybrid zones generally represent areas of secondary contact after speciation. The nature of the interaction between genes of individuals in a hybrid zone is of interest in the study of evolutionary processes. In this study, data from nuclear microsatellites and mitochondrial DNA sequences were used to genetically characterize hybridization between wild mongoose lemurs (Eulemur mongoz) and brown lemurs (E. fulvus) at Anjamena in west Madagascar. RESULTS: Two segments of mtDNA have been sequenced and 12 microsatellite loci screened in 162 brown lemurs and mongoose lemurs. Among the mongoose lemur population at Anjamena, we identified two F1 hybrids (one also having the mtDNA haplotype of E. fulvus) and six other individuals with putative introgressed alleles in their genotype. Principal component analysis groups both hybrids as intermediate between E. mongoz and E. fulvus and admixture analyses revealed an admixed genotype for both animals. Paternity testing proved one F1 hybrid to be fertile. Of the eight brown lemurs genotyped, all have either putative introgressed microsatellite alleles and/or the mtDNA haplotype of E. mongoz. CONCLUSION: Introgression is bidirectional for the two species, with an indication that it is more frequent in brown lemurs than in mongoose lemurs. We conclude that this hybridization occurs because mongoose lemurs have expanded their range relatively recently. Introgressive hybridization may play an important role in the unique lemur radiation, as has already been shown in other rapidly evolving animals.


Assuntos
Evolução Molecular , Hibridização Genética , Lemur/genética , Filogenia , Alelos , Animais , DNA Mitocondrial/genética , Genética Populacional , Genótipo , Haplótipos , Madagáscar , Repetições de Microssatélites , Polimorfismo Genético , Análise de Componente Principal , Alinhamento de Sequência , Análise de Sequência de DNA , Especificidade da Espécie
7.
Ecology ; 89(10): 2684-91, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18959306

RESUMO

Digestive physiology and movement patterns of animal dispersers determine deposition patterns for endozoochorously dispersed seeds. We combined data from feeding trials, germination tests, and GPS telemetry of Asian elephants (Elephas maximus) to (1) describe the spatial scale at which Asian elephants disperse seeds; (2) assess whether seasonal differences in diet composition and ranging behavior translate into differences in seed shadows; and (3) evaluate whether scale and seasonal patterns vary between two ecologically distinct areas: Sri Lanka's dry monsoon forests and Myanmar's (Burma) mixed-deciduous forests. The combination of seed retention times (mean 39.5 h, maximum 114 h) and elephant displacement rates (average 1988 m in 116 hours) resulted in 50% of seeds dispersed over 1.2 km (mean 1222-2105 m, maximum 5772 m). Shifts in diet composition did not affect gut retention time and germination of ingested seeds. Elephant displacements were slightly longer, with stronger seasonal variation in Myanmar. As a consequence, seed dispersal curves varied seasonally with longer distances during the dry season in Myanmar but not in Sri Lanka. Seasonal and geographic variation in seed dispersal curves was the result of variation in elephant movement patterns, rather than the effect of diet changes on the fate of ingested seeds.


Assuntos
Comportamento Animal/fisiologia , Elefantes/metabolismo , Fezes/química , Comportamento Alimentar/fisiologia , Germinação/fisiologia , Sementes/crescimento & desenvolvimento , Ração Animal , Animais , Trânsito Gastrointestinal , Sistemas de Informação Geográfica , Atividade Motora , Mianmar , Estações do Ano , Sri Lanka , Árvores
8.
PLoS One ; 7(12): e50917, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23236404

RESUMO

Human-elephant conflict (HEC) threatens the survival of endangered Asian elephants (Elephas maximus). Translocating "problem-elephants" is an important HEC mitigation and elephant conservation strategy across elephant range, with hundreds translocated annually. In the first comprehensive assessment of elephant translocation, we monitored 16 translocations in Sri Lanka with GPS collars. All translocated elephants were released into national parks. Two were killed within the parks where they were released, while all the others left those parks. Translocated elephants showed variable responses: "homers" returned to the capture site, "wanderers" ranged widely, and "settlers" established home ranges in new areas soon after release. Translocation caused wider propagation and intensification of HEC, and increased elephant mortality. We conclude that translocation defeats both HEC mitigation and elephant conservation goals.


Assuntos
Distribuição Animal , Conservação dos Recursos Naturais , Elefantes , Animais , Humanos , Sri Lanka
9.
Mitochondrial DNA ; 20(1): 7-14, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19565675

RESUMO

The ring-tailed mongoose (Galidia elegans) represents one of the most widely distributed mongooses in Madagascar; however, we know little about the ecology of this seemingly ubiquitous species. Currently, G. elegans is divided into three recognized subspecies--G. e. elegans, G. e. dambrensis, and G. e. occidentalis--based on differences in pelage coloration between the distinct geographic locations. We used intraspecific DNA variation to describe the phylogenetic relationships among the described subspecies. Approximately 550 base pairs of the mitochondrial DNA control region were analyzed from 19 G. elegans specimens representing all three subspecies sampled from across the species' geographic range. Sequence data from outgroup taxa were included for comparison. Examination of the recovered sequences revealed a strongly supported distinct genetic signature in the western region of the island, but remained inconclusive with respect to supporting the designation of the northern and eastern 'subspecies' for treatment as divergent intraspecific units for management.


Assuntos
DNA Mitocondrial/genética , Eupleridae/classificação , Eupleridae/genética , Animais , Sequência de Bases , Primers do DNA/genética , Variação Genética , Haplótipos , Madagáscar , Filogenia , Especificidade da Espécie
10.
Mol Phylogenet Evol ; 43(2): 674-84, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17270467

RESUMO

The systematic relationships of snakes in the Lampropeltis mexicana complex (L. mexicana, L. alterna, and L. ruthveni) are poorly known despite several taxonomic studies over the last 80 years. Mitochondrial DNA sequences were used to infer the phylogeny of the L. mexicana complex. At least one representative sample from the nine currently recognized species of Lampropeltis was sequenced. Our results suggest that a deep basal split resulted in the divergence of two groups of Lampropeltis, with one group occupying the upland areas of western United States and most of western and central Mexico, and the other northeastern Mexico and the lowland areas of the southern United States. Results also revealed that the L. mexicana complex and Lampropeltis triangulum are polyphyletic, with taxa from both groups nested together in deeply divergent northern and southern clades. These results are incongruent with previous hypotheses of phylogenetic relationships based on morphology, and suggest that morphological characters shared among the various tri-colored Lampropeltis (e.g., hemipenal structure and tri-colored pattern) may be difficult to interpret phylogenetically.


Assuntos
Colubridae/classificação , Colubridae/genética , DNA Mitocondrial/genética , Filogenia , Animais , México , NADH Desidrogenase/genética , RNA de Transferência/genética , Estados Unidos
11.
Proc Natl Acad Sci U S A ; 100(10): 5879-84, 2003 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-12719521

RESUMO

The lemurs of Madagascar provide an excellent model for exploring evolutionary diversification. This study investigates genetic divergence among most extant lemur taxa in relation to potential geographical boundaries to gene flow. For this purpose, approximately 2,400 bp of mitochondrial DNA (part of the COIII gene; ND3, ND4L, and ND4 genes; and five tRNAs) were sequenced in a total of 131 lemurs from 5 families, 12 genera, 25 species, and 18 subspecies to reconstruct phylogenetic relationships among them. The comprehensive range of taxa makes this a particularly suitable molecular data set to examine lemur evolution. Those data clearly reveal that the Betsiboka River acts as an isolating barrier between populations of lemurs in north-western Madagascar. The Tsiribihina River similarly serves as a barrier to gene flow between northern and southern populations of lemurs in central western Madagascar, whereas the Mahavavy River does not seem to lead to genetic isolation of lemur populations. Several discrepancies among molecular data, current taxonomy, and geographic distribution along the western coast emerged. Examination of geographical distribution of the taxa concerned in comparison with distribution boundaries of other lemur taxa in that region yielded explanations for these inconsistencies. Eulemur fulvus and Eulemur mongoz are the only lemur taxa that also occur outside Madagascar, on the Comoro Islands. Genetic data show no significant differentiation between Malagasy and Comorian populations of these species, supporting the interpretation that both were introduced only recently to the Comoro Islands.


Assuntos
Evolução Molecular , Lemur/classificação , Filogenia , Animais , DNA Mitocondrial/genética , Variação Genética , Geografia , Lemur/genética , Madagáscar
12.
J Hum Evol ; 43(4): 463-78, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12393004

RESUMO

The family Lemuridae includes four genera: Eulemur, Hapalemur, Lemur,Varecia. Taxonomy and phylogenetic relationships between L. catta, Eulemur and Hapalemur, and of Varecia to these other lemurids, continue to be hotly debated. Nodal relationships among the five Eulemur species also remain contentious. A mitochondrial DNA sequence dataset from the ND 3, ND 4 L, ND 4 genes and five tRNAs (Gly, Arg, His, Ser, Leu) was generated to try to clarify phylogenetic relationships w ithin the Lemuridae. Samples (n=39) from all ten lemurid species were collected and analysed. Three Daubentonia madagascariensis were included as outgroup taxa. The approximately 2400 bp sequences were analysed using maximum parsimony, neighbor-joining and maximum likelihood methods. The results support monophyly of Eulemur, a basal divergence of Varecia, and a sister-group relationship for Lemur/Hapalemur. Based on tree topology, bootstrap values, and pairwise distance comparisons, we conclude thatVarecia and Eulemur both represent distinct genera separate from L. catta. H. griseus andH. aureus form a clade with strong support, but the sequence data do not permit robust resolution of the trichotomy involving H. simus, H. aureus/H. griseus and L. catta. Within Eulemur there is strong support for a clade containing E. fulvus, E. mongoz and E. rubriventer. However, analyses failed to clearly resolve relationships among those three species or with the more distantly related E. coronatus and E. macaco. Our sequencing data support the current subspecific status of E.m. macaco and E.m. flavifrons, and that of V.v. variegata and V.v. rubra. However, tree topology and relatively large genetic distances among individual V.v. variegata indicate that there may be more phylogenetic structure within this taxon than is indicated by current taxonomy.


Assuntos
DNA Mitocondrial/genética , Lemuridae/genética , Filogenia , Animais , Reação em Cadeia da Polimerase , Alinhamento de Sequência
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