Communicating about communicating: when innate is not enough.

The cowbird is a brood parasite, providing no parental care to its offspring. The species has often been cited as a model of the usefullness of the construct of innate behavior, as an explanation of how young cowbirds develop species-typical behavior. Here we evaluate the adequacy of this perspective. We show that although it is difficult to explain ontogenetic beginnings without recourse to the concept of innate behaviors, ontogenetic outcomes are less easily accommodated. Constraints on the explanatory power of innateness as an ontogenetic concept are demonstrated with data from the development of singing in cowbirds and the development of babbling in human infants.