Parent-offspring conflict: A case of arrested development

The theory of parent-offspring conflict (POC) provides a plausible evolutionary foundation for the dissonant behavioral interactions commonly observed between adults and their progeny. It has been modelled extensively, but its predictions for phenotypes are murky and have been subjected to scant empirical testing. The least ambiguous cases are likely to involve taxa where offspring exert real power. Recent experimental work indicates that worker bees manipulate brood sex ratios differently from the queen. By contrast, most studies of avian brood reduction and mammalian 'weaning conflict' remain open to multiple interpretations. In general, POC may owe its current hegemony to the paucity of alternative explanations for parent-offspring squabbles. Reassessments of basic assumptions about what both parties 'really want' need to be linked to experimentation, field-oriented modelling and pluralism for this provocative theory to become broadly useful.