Demographic Ethology: Adaptive and Non-Adaptive Functions of Age-Specific Behavioral Characteristics in Fruit Flies

James R. Carey, University of California, Davis
Nikos Papadopoulos, University of Thessaly
Hans Muller, University of California, Davis
Jane-Ling Wang, University of California, Davis

The broad objective of this paper is to integrate life history theory, with its emphasis on demography, and ethology with its emphasis on evolutionary roots of animal behavior. Remarkably there appear to be only two sets of literature that contain information on age-specific behavioral characteristics: i) social insects (as Wilson states: “It would be difficult to overestimate the complexity of age polyethism… every category of social and individual behavior studied so far has proven to be affected … by age.” and ii) recent papers by Papadopoulos and co-workers on age-specific behavior in medflies (e.g supine behavior). There is no literature which establishes a coherency between demography and behavior. The specific goals of the current paper are to: i) present age-specific behavioral data on both the Mediterranean fruit fly and Drosophila; ii) interpret this behavior in adaptive, evolutionary contexts; and iii) generalize the concept of demographic ethology to include other species (including humans).