Inheritance of stereotyped gibbon calls

Abstract

Little is known about how vocal patterns develop in non-human primates, mainly because suitable controlled experiments are difficult to carry out on these animals1. Results of isolation experiments2-4and observations of interspecific hybrids1,5suggest no greater role for vocal learning than exists in many other vertebrates6-9, and less than has been found in birds10-13. We have now studied vocal patterns of hybrids between white-handed gibbons (Hylobates lar) and pileated gibbons (Hylobates pileatus) in natural mixed-species groups, in a zone of interspecies contact in central Thailand, and in some captive mixed-species groups. We find that in female hybrids, the patterns of the loud and stereotyped 'great-calls' show no evidence of learning from parents, and appear to be under strong genetic control. Daughters maturing in groups with genetically unlike parents develop great-calls unlike those of their mothers, even though these calls develop only while the daughters sing simultaneously with their mothers. © 1984 Nature Publishing Group.