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1.
Ecol Evol ; 10(15): 8030-8043, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32788959

RESUMO

Madagascar's ring-tailed lemurs (Lemur catta) are experiencing rapid population declines due to ongoing habitat loss and fragmentation, as well as increasing exploitation for bushmeat and the illegal pet trade. Despite being the focus of extensive and ongoing behavioral studies, there is comparatively little known about the genetic population structuring of the species. Here, we present the most comprehensive population genetic analysis of ring-tailed lemurs to date from across their likely remaining geographic range. We assessed levels of genetic diversity and population genetic structure using multilocus genotypes for 106 adult individuals from nine geographically representative localities. Population structure and F ST analyses revealed moderate genetic differentiation with localities being geographically partitioned into northern, southern, western and also potentially central clusters. Overall genetic diversity, in terms of allelic richness and observed heterozygosity, was high in the species (AR = 4.74, H O = 0.811). In fact, it is the highest among all published lemur estimates to date. While these results are encouraging, ring-tailed lemurs are currently affected by ongoing habitat fragmentation and occur at lower densities in poorer quality habitats. The effects of continued isolation and fragmentation, coupled with climate-driven environmental instability, will therefore likely impede the long-term viability of the species.

2.
Primates ; 52(4): 391-6, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21629992

RESUMO

In Madagascar, the gallery forests of the south are among the most endangered. Tamarind trees (Tamarindus indica) dominate these riverine forests and are a keystone food resource for ring-tailed lemurs (Lemur catta). At Berenty Reserve, the presence of tamarind trees is declining, and there is little recruitment of young trees. Because mature tamarinds inhibit growth under their crowns, seeds must be dispersed away from adult trees if tree recruitment is to occur. Ring-tailed lemurs are likely seed dispersers; however, because they spend much of their feeding, siesta, and sleeping time in tamarinds, they may defecate a majority of the tamarind seeds under tamarind trees. To determine whether they disperse tamarind seeds away from overhanging tamarind tree crowns, we observed two troops for 10 days each, noted the locations of feeding and defecation, and collected seeds from feces and fruit for germination. We also collected additional data on tamarind seedling recruitment under natural conditions, in which seedling germination was abundant after extensive rain, including under the canopy. However, seedling survival to 1 year was lower when growing under mature tamarind tree crowns than when growing away from an overhanging crown. Despite low fruit abundance averaging two fruits/m(3) in tamarind crowns, lemurs fed on tamarind fruit for 32% of their feeding samples. Daily path lengths averaged 1,266 m, and lemurs deposited seeds throughout their ranges. Fifty-eight percent of the 417 recorded lemur defecations were on the ground away from overhanging tamarind tree crowns. Tamarind seeds collected from both fruit and feces germinated. Because lemurs deposited viable seeds on the ground away from overhanging mature tamarind tree crowns, we conclude that ring-tailed lemurs provide tamarind tree seed dispersal services.


Assuntos
Lemur/fisiologia , Dispersão de Sementes , Tamarindus , Animais , Feminino , Preferências Alimentares , Madagáscar , Masculino , Sementes , Árvores
3.
Learn Behav ; 38(3): 220-34, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20628161

RESUMO

Interest in social learning has been fueled by claims of culture in wild animals. These remain controversial because alternative explanations to social learning, such as asocial learning or ecological differences, remain difficult to refute. Compared with laboratory-based research, the study of social learning in natural contexts is in its infancy. Here, for the first time, we apply two new statistical methods, option-bias analysis and network-based diffusion analysis, to data from the wild, complemented by standard inferential statistics. Contrary to common thought regarding the cognitive abilities of prosimian primates, our evidence is consistent with social learning within subgroups in the ring-tailed lemur (Lemur catta), supporting the theory of directed social learning (Coussi-Korbel & Fragaszy, 1995). We also caution that, as the toolbox for capturing social learning in natural contexts grows, care is required in ensuring that the methods employed are appropriate-in particular, regarding social dynamics among study subjects. Supplemental materials for this article may be downloaded from http://lb.psychonomic-journals.org/content/supplemental.


Assuntos
Animais Selvagens , Aprendizagem , Lemur/psicologia , Meio Social , Animais , Comportamento Alimentar , Feminino , Hierarquia Social , Comportamento Imitativo , Masculino , Destreza Motora , Resolução de Problemas , Projetos de Pesquisa , Comportamento de Utilização de Ferramentas
4.
Am J Primatol ; 72(5): 391-406, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20039330

RESUMO

Few Malagasy children and adults are aware of the rare and unique fauna and flora indigenous to their island-continent, including flagship lemur species. Even the Malagasy ancestral proverbs never mentioned lemurs, but these same proverbs talked about the now extinct hippopotamus. Madagascar's geography, history, and economic constraints contribute to severe biodiversity loss. Deforestation on Madagascar is reported to be over 100,000 ha/year, with only 10-15% of the island retaining natural forest [Green & Sussman, 1990]. Educating children, teacher-training, and community projects about environmental and conservation efforts to protect the remaining natural habitats of endangered lemur species provide a basis for long-term changes in attitudes and practices. Case studies of three conservation education projects located in different geographical regions of Madagascar, Centre ValBio, Madagacar Wildlife Conservation Alaotra Comic Book Project, and The Ako Book Project, are presented together with their ongoing stages of development, assessment, and outcomes. We argue that while nongovernmental organizational efforts are and will be very important, the Ministry of Education urgently needs to incorporate biodiversity education in the curriculum at all levels, from primary school to university.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais/métodos , Ecossistema , Lemur , Animais , Criança , Conservação dos Recursos Naturais/economia , Humanos , Madagáscar , Organizações , População Rural , Instituições Acadêmicas
5.
Am J Primatol ; 71(3): 183-90, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19142988

RESUMO

Coat condition can be influenced by a wide variety of disorders and thus provides a useful tool for noninvasive health and welfare assessments in wild and captive animals. Using Lemur catta as an exemplar, we offer a 6-step scoring system for coat and tail condition, ranging from perfectly fluffy to half or more of body and tail being hairless. The categories are described in detail and illustrated with sample pictures from a wild population in Berenty Reserve, Madagascar. Furthermore, we elaborate on intermediate conditions and discoloration of fur. Coat condition scoring allows the comparison between years, seasons, and the effect of toxin, disease or stress. Although this system was developed for wild L. catta, we believe it can also be of value for other species. We recommend scoring coat condition in healthy wild mammal populations to give a baseline on yearly and seasonal variations vs. deteriorating health conditions or pathology.


Assuntos
Cabelo/fisiologia , Indicadores Básicos de Saúde , Lemur/fisiologia , Cauda , Alopecia/fisiopatologia , Alopecia/veterinária , Animais , Cor de Cabelo/fisiologia , Nível de Saúde , Estações do Ano
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