 Khalidi (2002) identifies a further objection to the proposal that innateness can be defined as invariance across some “normal” range of environments. Sometimes, he notes, the strongest evidenced that a trait is innate is its capacity to develop in highly abnormal conditions. Consider the deprivation experiments deployed by early ethologists, where animals were raised in social isolation or other impoverished circumstances. The tendency for a trait to develop even under these (abnormal) conditions was regarded as strong evidence of its innateness. From this perspective it seems utterly wrong-headed to define innateness in terms of some normal range, so long as “normal” is defined as the environments which a species typically encounters.