Reproductive sharing in animal societies: reproductive incentives or incomplete control by dominant breeders?

• DOI: 10.1093/beheco/9.3.267
• Publication Date: 2007-01-13T11:47:48Z
• Authors: H. Kern Reeve; Stephen T. Emlen; Laurent Keller
• Keywords: Cooperative breeding

Optimal skew models explain reproductive sharing within social groups as resulting from incentives given by controlling dominants to subordinates in return for peaceful cooperation. We explore two versions of an alternative, the incomplete control model, evolution groups. In this have only limited over allocation reproduction and must expend effort increase their share total group output show that, when relatedness between dominant subordinate is symmetrical, (1) subordinate's fraction either increases with, or insensitive to, genetic relatedness, r, both whereas decreases with increasing r optimal (2) model exceed that (3) ecological factors affecting solitary breeding success do not directly affect but model. When dominant-subordinate asymmetrical (as often case parent-offspring associations), predicts no offspring regardless size containing any mixture unrelated full-sibling subordinates, predict such possible three more. The available evidence indicates a negative relationship vertebrate hymenopteran societies, apparently supporting predictions skew, control, class models. However, necessarily inconsistent when, true some studies, it results comparison skews genetically monogamous, nonincestuous parents (asymmetric relatednesses) nonkin (symmetric relatednesses). Both higher associations. Occasional are larger than dyads more consistent however. Overall, current data on its relationships intragroup aggression constraints support needed rule out These examples different general views intrasocietal evolution: tug-of-war view, which members engage struggle resources, transactional exchange parcels induce beneficial behavior each other.