the ultimate source of new variation in nature is
Genetic variation Genetic variation is brought about, fundamentally, by mutation, which is a permanent change in the chemical structure of chromosomes. Genetic recombination also produces changes within alleles.
Criticism of evolutionary psychology Evolutionary psychology has generated substantial controversy and criticism. The criticism – which has been most forceful from proponents of constructivist, postmodernist and poststructuralist schools of thought – includes but is not limited to: disputes about the testability of evolutionary hypotheses, alternatives to some of the cognitive assumptions (such as massive modularity) frequently employed in evolutionary psychology, alleged vagueness stemming from evolutionary assumptions (such as uncertainty about the environment of evolutionary adaptation), differing stress on the importance of non-genetic and non-adaptive explanations, and political and ethical issues.[1]