Egg polymorphism and highly sensitive egg recognition of cross-phenotypes in rufescent prinias Prinia rufescens as effective defenses against brood parasitism

摘要

Whether escalating egg polymorphism increases the efficiency to reduce the fitness costs of brood parasitism is not supported by empirical studies. Rufescent prinias (Prinia rufescens) laying tetramorphic eggs are highly sensitive to conspecific foreign eggs with different phenotypes that they reject perfectly at 100%, and suffer only 1.4% of plaintive cuckoo (Cacomantis merulinus) parasitism. Our study provided empirical evidence showing that escalation of egg polymorphism in hosts increases their fitness because it reduces successful cuckoo parasitism rate.