In Mandrill Society, Life is a Girl Thing
Mandrills in Lope Reserve of Gabon are observed living in large groups, some numbering over a thousand, and these groups are made up almost entirely of females and their dependent offspring; males move into the group at beginning of a breeding season and disappear once it is through; their battles for mates are fierce and punishing, and their remarkable coloration may be a way of minimizing violence; scientists are concerned that mandrills will increasingly fall prey to bush meat trade as logging roads open deep forests; photos; map; drawing (M)