THE ADAPTIVE SIGNIFICANCE OF SOCIAL SYNCHRONIZATION OF ULTRADIAN BEHAVIOR CYCLES - A COMPUTER-MODEL

Daily behaviour patterns in a hunter-gatherer community of Colombian I ndians show that individual activities are regulated by ultradian beha viour cycles of about 2 hr and that these cycles can be synchronised b y social interaction. A computer model was developed which simulated a n artificial community and generated dynamic portraits of locomotor ac tivity and social aggregation similar to those of the observed communi ty of Colombian Indians. Social phase-locking of ultradian behaviour c ycles occurred, contributing to the safety of group members and their economy of effort in gathering and related activities. Social synchron isation of ultradian behaviour cycles may also have occurred in early hominid groups.