The causes and consequences of kin recognition in the cooperatively breeding cichlid Neolamprologus pulcher

摘要: Kin recognition allows individuals to assess their relatedness conspecifics, thus they may then show kin discrimination and make informed choices as with whom associate and/or breed. Cooperatively breeding species, such the cichlid Neolamprologus pulcher, are an excellent model system for investigating recognition, live in complex social groups, containing both non-kin group members. Cooperation involves helping rear offspring of dominant pair. Helping is costly, but helpers gain direct fitness benefits through living a group, if aid relatives, can also indirect selection. Furthermore, by being able recognise kin, avoid inbreeding potentially deleterious consequences it. Thus, N. pulcher predicted have good abilities. In this thesis, I investigate its mate choice captive population pulcher. chapter 2, investigated capabilities juvenile whilst controlling familiarity. found that preferred unfamiliar over non-kin. was via some form phenotype matching, chemical cues more important than visual cues. Additionally, no between familiar kin; thus, rather familiarity association preferences Chapter 3 explored whether pair, or differences individual behavioural types affected amount type shown Controlling size helper relatedness, breeders had influence on help carried out. selected alone cannot explain variation behaviour The territory maintenance out correlated defence, were consistently helpful. Individuals varied aggressiveness, risk-responsiveness activity levels, these traits did not correlate one another. More aggressive, risk-prone active defence submissive, risk-averse inactive helpers. contrast, helpers, types. explained relatedness. Since motivation might vary age state, 4, avoided when sexually mature, examined inbreeding. standard two-way tests, male showed associating sisters female non-kin, brothers However, given opportunity breed, latency breed hatching success differ brother-sister pairs unrelated pairs. actively does appear be detrimental fitness. suggest sex-biased dispersal regular breeder replacement territories minimise occurrences wild opportunistic, strategic decision. final theme my thesis effect phenotypic choice. (chapter 4) individual’s facial stripe, which varies individuals, played role preferences. body non-cooperatively green swordtail, Xiphophorus hellerii. 5, males large small females presented only cues, differential increased, larger based So, X. hellerii prefer females, fecund hence, bring them greater returns. conclusion, study has ability do compel directed cooperation, avoidance. Instead, factors decisions help, Overall, project shows under conditions we tested, selection drive interactions groups. Further, it highlights need consider multiple affecting fitness, order fully understand why different species propensity discriminate