Alocação de recurso materno mediada pela qualidade do cuidado parental dos machos no peixe amazônico Crenuchus spilurus

Abstract

The differential allocation hypothesis predicts that females are able to allocate energetic resources to eggs according to characteristics of the environment, including the quality of mating partner. Male quality can be evaluated through ornamentation, as it represents a signal that is easy to assess by females and can convey information on direct and indirect fitness benefits to the female. We investigated carotenoid resource allocation to eggs in females of the sailfin tetra (Crenuchus spilurus), a fish species with paternal-only care. We assessed female resource allocation as a response to ornamentation of paired males during reproduction. By inspecting the color of eggs, we show that females produced oocytes richer in carotenoid when paired with highly ornamented males. By investigating time in egg fanning, we show that more ornamented males put more effort in paternal care. We suggest that male quality is honestly signaled by the ornaments, which stimulate females to allocate more resources to the oocytes that will be fertilized and under care of higher quality males. We propose mutual stimulation by males and females during reproduction in C. spilurus: while ornaments trigger increased allocation of resources to the oocytes, the color of eggs laid by females triggers further resource allocation to the offspring in the form of higher paternal care by males.