Mating success and sexual selection in a pelagic copepod, Temora longicornis : Evidence from paternity analyses

Abstract

Knowledge about mating patterns is essential for understanding and explaining rates of reproduction and genetic potential of copepods populations. The aim of this study was to examine (1) the occurrence of multiple paternity in Temora longicornis, (2) the effect of multiple paternity (if present) on the females reproductive output, and (3) whether mating is random or some individuals have a higher than average chance of fertilizing or being fertilized (super individuals). We show that multiple paternity is common in this copepod species, that females benefit from multiple matings by increased offspring production, and that a relatively small fraction of the males and females in a population account for most of the offspring production. In both males and females, mating is nonrandom. Superior individuals with a higher than average matings success were identified both among females and among males.

Paternal energetic investments in copepods

“…The large proportion of the male body that is occupied by genital organs also indicates strong selection for investment in spermatophore production. A recent study documents multiple paternities in Temora , suggesting sperm competition (Sichlau et al ), which implies that investing in spermatophore content that promote fertilization is rewarding.…”

“…Multiple paternity clutches is demonstrated in parasitic and pelagic copepods (Todd et al ; Sichlau et al ), suggesting sperm competition and selection for qualities in spermatophores that promote fertilization. Also, males select mates that are young and large (Ceballos and Kiørboe ; Sichlau et al ), further indicating a mating cost for the males. The idea that spermatophore production might be costly is not new (Kiørboe ; Titelman et al ).…”