Stimuli governing intraspecific egg predation in the flour beetles,Tribolium confusum andT. castaneum

Summary The present research has not identified all of the factors that interact to produce the observed egg cannibalism rates inTribolium. It has, however, shown that some physical and chemical properties of the egg and environment play an important role in determining cannibalistic activity in a population. Of general interest is the observation that cannibalism is not solely the result of the biological characteristics of the cannibal. While it is generally acknowledged that the quality and quantity of food may influence the intensity of cannibalism, it is not generally recognized that the environment can affect cannibalism in as complex a manner as is suggested by the current research. That two such closely related species, and even two life-stages of the same species, may respond so differently to the same environmental cues is impressive. Predicting the intensity and hence the importance of cannibalism in natural populations may be difficult without detailed empirical studies.