Original Research ArticleTime scaled phylogeography and demography of Bradypus torquatus (Pilosa: Bradypodidae)

The maned sloth Bradypus torquatus (Bradypodidae:Pilosa) is an endangered and endemic species of the Atlantic Forest in Brazil, a biome that was anthropogenically reduced to about 7% of its original extent. Nowadays, an apparently decreasing population is restricted to few remaining rainforest fragments. We analyzed nuclear and mitochondrial genes of 69 individuals from the Brazilian states of Bahia, Espírito Santo and Rio de Janeiro to estimate their current and historical population dynamics. The diversification history of B. torquatus populations was mainly led by dispersal and vicariant events occurring during Pliocene and Pleistocene associated to several climatic and vegetation changes. Besides, the current distribution of remaining populations was also likely affected by recent anthropogenic deforestation occurring in the last five centuries in Brazil, resulting in local extinction of many intermediate B. torquatus populations. Our time scaled phylogeographic results indicate that in the Pliocene, an ancestral population of B. torquatus was originally located in the intermediate Atlantic Forest region between BA and ES states and dispersed northwards and southwards to its current range. These results indicate also that the northern and southern Atlantic Forest B. torquatus lineages should have independent management plans and conservation policies due to their ancient history of isolation and evolutionary independency.