Dynamic games and field experiments examining intra- and intersexual conflict: explaining counterintuitive mating behavior in a Mediterranean wrasse, Symphodus ocellatus

Intersexual conflict and intrasexual competition are widelyrecognized asplaying critical roles in determining mating systems.Although they occursimultaneously in populations, these processesare usually treatedindependently. In reality, the fitness ofreproductive strategies will dependon the outcome of both within-and between-sex conflicts. Using a modelingapproach based onmultiple, linked, dynamic state variable models, we examinedthereproductive behavior of a Mediterranean wrasse, Symphodusocellatus.We compared the predictions of models that examine only asingleconflict interaction with those that consider multiple within-andbetween-sex conflicts simultaneously. The observed distributionof sneakermales and females among nests was compared with thosepredicted by the models.We found that the closest fit withempirical observations and experiments isgiven by the modelthat examines conflict between females, sneakers, andnestingmales simultaneously. Removal of successful nests indicatedthatfemales join nests with few or no sneakers present, whereassneakers jointhese nests only later, even though this leadsto lower sneaker matingsuccess. This behavior can be explainedby observing that although sneakerswould have higher fitnessat nests where the spawning rate is greater, femaleswould notbe willing to spawn at these nests in the presence of sneakers.Presumably,once the nests have achieved high past success, females arewillingto spawn in the presence of sneakers because of the associateddecreasedchance of nesting male desertion.