The initial response of females towards congeneric males matches the propensity to hybridise in Ophthalmotilapia

• DOI: 10.26496/bjz.2022.100
• Publication Date: 2022-04-13T13:23:00Z
• Authors: Maarten Van Steen...; Noémie Jublier; Loïc Kéver; Sophie Gresham; Sophie Derycke; Jos Snoeks; Eric Parmentier; Pascal Poncin; Erik Verheyen
• Keywords: Cichlid

Cichlid radiations often harbour closely related species with overlapping niches and distribution ranges. Such sometimes hybridise in nature, which raises the question how they can coexist. This also holds for Tanganyika mouthbrooders Ophthalmotilapia ventralis O. nasuta. Earlier studies found indications of asymmetrical hybridisation females accepting males nasuta, but not other way around. We hypothesised that this was due to differences capacity recognition. Given higher propensity towards hybridisation, we expect a reduced ability recognition females, compared nasuta females. staged two experiments, one focusing on 22 female 21 ventralis. These fish were placed half tank briefly exposed conspecific or heterospecific male, female, nothing (control). Female response evaluated by scoring six tracking parameters noting occurrence ten discrete behaviours before during encounter. Females always responded presence another approaching it. Remarkably, both ventralis, did find different between encounters However, agreement our hypothesis, behaved differently males, whereas not. When presented performed lower number ‘ram’ behaviours. Additionally, never displayed ‘flee’ behaviour, component species’ mating repertoire seen all presentations male. Our findings show at first encounter predict large degree outcome process, even absence behaviour.