Is size assortative mating in Paracalliope fluviatilis (Crustacea: Amphipoda) explained by male–male competition or female choice?

摘要: Field and laboratory studies were used to assess: (1) whether size assortative mating occurred in the New Zealand amphipod Paracalliope fluviatilis (2) hypotheses developed explain mating. We found that larger females carried more eggs, suggesting they may be valuable as mates. Laboratory experiments then determine whether: male influenced of female selected (mechanical constraints hypothesis); pairing success presence competition (intrasexual selection (3) take-overs large males successful (4) guard duration varied relative (guard (5) had control over (intersexual hypothesis). Although there was evidence suggest existence intrasexual for mates (i.e. both small preferred females), no overt takeovers paired females). There also difference with respect how long guarded females, but longer by classes. Females handicapped having their mobility reduced same likely pair easier amplex. Given lack direct male–male or choice, we result of: indirect (e.g. situ better able access amplex largest females) resistance combination higher costs incur securing females. © 2007 The Linnean Society London, Biological Journal Society, 2007, 92, 173–181.