 Some philosophers take this as sufficient grounds for rejecting any analysis of innateness in terms of genetic contributions (e.g. Khalidi 2007). The worry is that there is no canonical comparison class for evaluating the relative contributions of genetic and environmental influences. Different researchers will select different alleles and different environments for investigating a given trait and there is no non-arbitrary way to determine which is the “correct” comparison class. Insofar as innateness is not a context sensitive concept, but the magnitude of genetic contribution is highly context sensitive, innateness cannot be defined as magnitude of genetic contribution. One way to potentially avoid this implication is by specifying a canonical or “normal” range of environments. In this view, a trait is relatively innate to the extent that genetic (as opposed to environmental) factors explain phenotypic differences across the normal range of environments. This proposal will be considered more carefully in the following section (Section 3.2) Interested readers might refer to entries on  Gene  and  Biological Information).