Sep. 19, 2002 Eavesdropping among animals influences their
behavior, Lee Dugatkin, an evolutionary biologist at the
University of Louisville, has found. Dugatkin and a colleague,
Ryan Earley of Georgia State University, studied eavesdropping
among male swordtail fish they placed in an experimental tank.
They put two fish on one side of a partition and a lone observer
male on the other. In some cases, the partitions were clear and
in others, opaque. The fish that could observe their potential
adversaries fighting through the clear partition were less
likely to defeat the winner of the fight. "We were able to
separate winning and losing streaks based on eavesdropping,"
Dugatkin says. Psychological factors such as simply watching a
fight seem to have a drastic effect on animal societies and the
levels of aggression within them, he adds. "My own studies
indicate that they (psychological factors) can be used to make
predictions such as whether interactions between group members
will be autocratic or meritocratic …