Parental coordination with respect to colour polymorphism in a crater lake fish

In many taxa, success in parental care requires the coordinated efforts of both parents. Given the evolutionary potential of parental performance, as well as phenotype-related behavioural differences, it is surprising that parental coordination in polymorphic species has attracted only very limited research attention. To redress this gap, I combined multiple approaches to assess parental performance and coordination of parental effort in the colour polymorphic and biparental cichlid fish, Amphilophus sagittae, in its natural crater lake habitat. I compared parents of the two colour morphs, dark and gold, as well as pairs that had mated colour assortatively ('same colour' pairs) versus disassortatively ('mixed' pairs). The two morphs differed in terms of a higher than expected number of single gold morph parents. Interestingly, parental coordination, in terms of the size of the defended territory and the rate of aggressive responses towards natural territory intruders, was lower in mixed...