  Feminist and non-feminist philosophers of biology have made it clear that even if a trait is the result of evolution by natural selection, or in other words is an adaptation, it does not follow that the trait is uniformly expressed in a population or static in an individual over time. Some adaptive traits are almost always present and others require very specific environmental conditions in order to develop. One could have the genetic correlate of a trait and that trait could be the result of natural selection, and yet changing the environment could eliminate the expression of that trait. Some traits are adaptations to past environmental conditions and are not beneficial to organisms in current conditions. Some traits are present and very beneficial, and yet are not the result of natural selection and hence are not adaptations. Simple pictures of biological determinism are thus not supported by evolutionary biology (for example see Keller 2000).