Genetic consequences of habitat fragmentation in black and gold howler populations from northern Argentina.

OKLANDER L.I. KOWALEWSKI MM CORACH D D.

INTERNATIONAL JOURNAL OF PRIMATOLOGY

SPRINGER/PLENUM PUBLISHERS

Año: 2010 vol. 31 p. 813 - 832

0164-0291

Human-induced habitat fragmentation might seriously affect behavioural patterns and the survival of species whose ecological requirements strongly depend on specific environmental conditions. We compared the genetic structure and dispersal patterns of two populations of Alouatta caraya (Plathyrrhini, Atelidae) to understand how habitat reduction and fragmentation affect gene flow in this species. We sampled individuals from 7 groups living in continuous forest (CF, N=46, 22 males and 24 females), and 11 groups that inhabit a fragmented forest (FF, N=50, 24 males and 26 females). FST values based on 11 microsatellite loci showed a recent genetic differentiation among groups in the FF. In contrast, the CF showed no differentiation among groups. Furthermore, FST values between sexes, as well as kinship relationships, also exhibited differences between habitats. In the CF, both males and females disperse, leading to non-differentiated groups composed by adults that are not close relatives. Conversely, in the FF, some groups are differentiated, males disperse more than females and groups are composed by closely related adult females. Our results suggest that habitat fragmentation modifies the dispersal patterns of black and gold howler monkeys. These differences between habitats may reflect a reduced gene flow, providing genetic evidence which suggests that habitat fragmentation severely limits the howler’s ability to disperse. An increasing level of isolation due to uncontrolled deforestation may cause similar loss of genetic diversity on other arboreal primates, and non primates that depend on forest continuity to disperse, reducing their abilities to cope with environmental changes.