Aged Eisenia fetida earthworms exhibit decreased reproductive success

摘要

The effect of age on male and female reproductive activity was examined in 1-6-year-old age-matched populations of the simultaneous hermaphroditic earthworm, Eisenia fetida, (Annelida; Oligochaeta). As earthworm ages increase from 3- to 6-years, cocoon and hatchling production gradually decreased. Sperm counts from 2-year old and 5-year old earthworms did not differ. Old earthworms successfully inseminated young virgin earthworms. Thus, female functions associated with successful cocoon production diminish before the male function. These results indicate that E. fetida earthworms spend up to one-third of their adult life with limited reproductive capabilities.