As emphasized in early cultural evolutionary theory, understanding heritability of human traits – especially, behavioural traits – is difficult. The target article describes important ways that culture can enhance, or obscure, signatures of heritability in genetic studies. Here, we discuss the utility of calculating heritability for behavioural traits influenced by cultural evolution and point to conceptual and technical complications to consider in future models.

Baumard's perspective asserts that “opportunity is the mother of innovation,” in contrast to the adage ascribing this role to necessity. Drawing on behavioral ecology and cognition, we propose that both extremes – affluence and scarcity – can drive innovation. We suggest that the types of innovations at these two extremes differ and that both rely on mechanisms operating on different time scales.

Here, we compare birdsong and human musicality using insights from songbird neuroethology and evolution. For example, neural recordings during songbird duetting and other coordinated vocal behaviors could inform mechanistic hypotheses regarding human brain function during music-making. Furthermore, considering songbird evolution as a model system suggests that selection favoring certain culturally transmitted behaviors can indirectly select for associated underlying neural functions.