FRACTAL STRUCTURE OF SEQUENTIAL BEHAVIOR PATTERNS - AN INDICATOR OF STRESS

The detection of stress arising from parasitic infection by Sarcoptes scabieis and from pregnancy is explored, using a fractal analysis of h ead lifting behaviour and feeding-non-feeding activity sequences in fe male Spanish ibex, Capra pyrenaica, under natural conditions. Because organisms under stress increase their metabolic rate and, in consequen ce, energy consumption, it follows that stress will, generally, lead t o a reduction in complexity (fractal dimension) of exploratory behavio ur. In the present study the fractal dimension of the three measures o f complexity used declined with stress, both from pregnancy and from p arasitic infection. This observation provides a new and effective way to assess the general state of animals' health in the field, without t he need for capture and handling. (C) 1996 The Association for the Stu dy of Animal Behaviour