"The Molecular Systematics of Leontopithecus, Population Genetics of L. chrysopygus and the Contribution of these two Sub-Fields to the Conservation of L. chrysopygus" by Deniz Unsal

Beatriz Michelle C Perez-Sweeney

Deposited 2002

Abstract
This thesis focuses on the evolutionary history of L. chrysopygus (a critically endangered primate endemic to the state of São Paulo, Brazil), and applies the findings to their conservation management. The evolutionary history of L. chrysopygus was investigated on both a macro- and microevolutionary level using genetic data.

On a macroevolutionary level, the mitochondrial genetic data suggest that there are three distinct lion tamarin species (L. chrysomelas, L. caissara and L. chrysopygus/L. rosalia ) and that L. chrysopygus and L. rosalia are closely related and they could be considered subspecies. The phylogenetic reconstruction did not place L. caissara as subspecific or even sister to L. chrysopygus as was previously proposed from pelage color. The phylogenetic data also suggest that lion tamarin diversification may have been shaped by Quaternary forest refuges (with the oldest refuge located in Bahia), but diversification was not shaped by metachromism.

On a microevolutionary level, the distribution of mitochondrial versus nuclear microsatellite variation reflects a pattern of limited female dispersal relative to male dispersal. Additionally, an analysis of the data under Nested Cladistic Analysis suggests that an historical range expansion event occurred. Finally, the results suggest that anthropogenic fragmentation has not interfered with the genetic structure to the point of masking the natural genetic structure of black lion tamarins, but has decreased the genetic variation present in the taxon.

The black lion tamarin conservation management recommendations based on the genetic research are as follows. First, while black lion tamarins show some genetic distinction from the other lion tamarins, it is the combination of genetic, ecological and morphological differentiation that support their treatment as a unique conservation unit. Second, black lion tamarins still have a considerable amount of genetic variation and we should thus be concerned about the potential future loss of genetic variation from anthropogenic fragmentation. Third, there are two clearly distinct regions, Central São Paulo and the Pontal (Western São Paulo), that could be treated as separate management units. Finally, each of the distinct regions is internally similar by nuclear DNA and the populations within these regions could thus be managed as members of the same population.

Overall, in addition to providing an understanding of the evolutionary history of black lion tamarins, this research demonstrates that molecular genetics can be quite useful to conservation management.