Text 1
A young bird, it seems, carries its song within it from the start. Certain species reared in isolation, never having heard an adult of their kind, still grow up to produce the full, recognizable song of their species, and they do so on a fixed developmental schedule. To the researcher Devlin, this argues that the essential pattern is inherited — an inborn template that unfolds as the bird matures. Experience may polish the performance, but the score, on this view, is written in advance.
Text 2
Other work tells a different story. In many songbirds, a nestling kept from hearing adult singers grows up to produce only a thin, malformed song, and neighboring populations of the same species sing in distinct local dialects that a young bird picks up by copying the adults around it during a brief sensitive period. For the researcher Amara, this points to learning: the young bird does not unspool a finished score but assembles its song from the models it hears, and one that hears no model is left without a proper song at all.
Based on the texts, which choice best describes a central difference in how the two texts explain the development of birdsong?