Genetic differentiation within and between isolated Algerian subpopulations of Barbary macaques (Macaca sylvanus): evidence from microsatellites

Abstract

This study of wild-living Algerian Barbary macaques (Macaca sylvanus) was designed to examine genetic variability in subpopulations isolated in residual forest patches, in an attempt to obtain data on the effects of habitat fragmentation. The wild population of this species (estimated at a maximum of 15,000) is vulnerable and this study therefore has direct relevance for conservation measures. Data from five microsatellite loci were analysed for 159 individuals from nine different groups living in four isolates in Algeria. Genetic polymorphism was found to be relatively high (4-12 alleles per locus) compared with other genetic markers used in previous studies of this species; mean expected heterozygosity was 65%. The four isolates are all genetically distinct (FST = 0; P < 0.001). Indeed, the results suggest that dispersal is limited even between some social groups within a single isolate. Genetic distances based on models not assuming stepwise mutation (FST and chord distance) gave very similar results and are highly correlated with geographical distances within one isolate but not between isolates. This may indicate that isolation by distance exerts a significant influence within an isolate but that genetic drift prevails between the four isolates. After allowing for variation in sample size, we found no evidence of reduced allelic diversity within small isolates that may have been separated for 250 years or more. The surviving population of Algerian Barbary macaques taken as a whole still shows marked variability in microsatellite alleles, but maintenance of genetic variability over the long term will surely require effective protection of all isolates.

Phylogeography of Barbary macaques ( Macaca sylvanus ) and the origin of the Gibraltar colony

“…Furthermore, the Kherrata population displays the greatest variability despite having the smallest sample size. Similar findings have been reported in a previous study of microsatellites, in which Kherrata was found to have the highest number of private alleles in one social group (32). However, the presence of three markedly divergent mtDNA lineages in Algeria suggests that the observed geographical patterns probably arose through extinction of intermediate populations and physical barriers to dispersal between regions.…”

“…1). For the Algerian lineages, this finding concords with a previous study based on microsatellites (32). Of particular interest is the initial split occurring at Ϸ1.6 mya, dividing the Moroccan clade and one major Algerian clade from a second major Algerian clade (Fig.…”

Male and Female Reproductive Success in Macaca sylvanus in Gibraltar: No Evidence for Rank Dependence

“…It is known that 9 of the latter systems-D1S207, D2S141, D6S311, D7S503, D8S1106, D11S925, D16S420, D17S791, and D18S536-show variation in Barbary macaques (Lathuillière et al, 2001;von Segesser, 1999;von Segesser et al, 1999) and that the 3 remaining systems-D2S305, D3S1279, and D4S243-show polymorphism in other Old World monkeys (Nair et al, 2000;von Segesser, personal communication) and were successfully amplified in M. sylvanus. Most of the microsatellite sequences we examined consisted of CA repeats, but the 3 markers D4S243, D8S1106, and D18S536 contained GATA tetranucleotide repeats.…”

An Overview of the Barbary Macaque, Macaca sylvanus, Vocal Repertoire

“…Based on fossil and morphological [12], and molecular evidence [13][14][15], Barbary macaques form a separate species group, placed at the base of the clade Macaca, being a sister group to all Asian macaques. Presently, their occurrence is restricted to the mountainous regions of Algeria and Morocco [16,17]. Barbary macaques are largely terrestrial during the day, but climb into trees and sleeping cliffs during the night and also during day-time resting periods [18,19].…”