ABSTRACT
To understand the nature of any species fully, we need to know more than the ways of its adults. We need to know how its young are brought from initial, infantile inadequacy to mature, species-typical functioning. Variation in the uses of immaturity tells much about how adaptation to habitat is accomplished, as well as what is likely to happen given a change in habitat. The nature and uses of immaturity are themselves subject to evolution, and their variations are subject to natural selection, much as any morphological or behavioural variant would be.
