Selective Egg Cannibalism in Sinella Curviseta (Collembola: Entomobryidae)

Abstract

Sinella curviseta eggs less than 24 hours of age are smooth; older developing eggs are rough. An experiment was concluded to analyze egg cannibalism in unisexual populations exposed to eggs on both types. This experiment demonstrated that egg consumption (i) averaged .03 eggs per animal per hour, (ii) occurs at a significantly higher rate in females than in males, and (iii) is almost completely (99%) confined to smooth eggs. As smooth eggs include very young eggs and faulty eggs of any age, smooth eggs have a lower probability of reproductive success than rough ones. Animals encounter in a clutch first smooth eggs with less chance of hatching; later, smooth eggs with a still probability of success (as more developing ones have become rough); and finally, during the final 72% of the period of exposure to a clutch, smooth eggs whose probability of hatching is effectively zero. It is efficient resource utilization to ingest these eggs.