Spermatophore consumption in a cephalopod

Abstract

An individual's gametes can represent a nourishing food source for a manipulative mate. Here, we provide evidence of ejaculate and sperm consumption in a cephalopod. Through labelling male spermatophores with 14 C radiolabel, we found that female squid, Sepiadarium austrinum , consumed the spermatophores of their partners and directed the nutrients received into both somatic maintenance and egg production. We further show that in this species—where fertilization occurs externally in the female's buccal cavity—sperm storage is short-term (less than 21 days). The combination of female spermatophore consumption and short-term external sperm storage has the potential to exert strong selection on male ejaculates and reproductive strategies.