Genetic self-management in a captive colony of mandrills (Mandrillus sphinx) as revealed by DNA minisatellite fingerprints

DNA fingerprints using three oligonucleotide probes, a (GTG)5 short tandem repeat sequence, and 2 corresponding to the core sequences of minisatellites 33.15 and 33.6, have been used to generate DNA fingerprints of a captive colony of mandrills (Mandrillus sphinx) housed at the Centre International de Recherches Medicales de Franceville (CIRMF), in order to monitor paternity. A colony of 6 males and 7 females was established in a 6 ha. rain-forested enclosure in 1983. Band sharing scores indicated that none of the founders were related. By April 1994 the colony had increased to 84 individuals. Forty-nine of the 77 births were first-generation infants, a further 27 were second-generation offspring, and one was a third-generation mandrill. Five animals died during the study, and one was removed for husbandry reasons. Overall band sharing between individuals increased markedly and the power to discriminate between first- and second-generation infants was reduced; the probability of two individuals sharing the same pattern increased 1000-fold from 10−6 to 10−3. The dominant male in the group effectively guards access to all receptive females during the annual breeding season. Paternity analysis confirmed that the dominant male is the father of the great majority of offspring born during his term of dominance. Daughters born before 1991 to either of the two dominant males reached sexual maturity during his tenure. Incestual inbreeding occurred with both males, but only 25% of all possible cases resulted in the birth of a viable infant; one male fathered infants on 3 of 13 possible occasions and a second male on 2 of 7 occasions. Female avoidance strategies and shifts in male dominance in this closed mandrill colony appear to be timed in a way that reduces incest.