2. Pigliucci and Kaplan (personal communication) say that they did not intend to endorse DOA, but rather that they think that drift is caused by indiscriminate sampling as well as various random events at the level of individuals.. Their view is different from DOA, they contend, in that they think “drift” can refer either to the difference between the actual changes in a population and those changes that would be predicted from the differences in fitness or to the degree of ‘scatter’ around the (expected) mean changes in the population (the shape and size of the distribution). Perhaps this might be seen as a variant of DOA.

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