 Griffiths and Machery (2008) mention another consideration that makes the prospects for conceptual unification seem even less promising. They note that the kinds of environmental factors that influence trait development are often highly surprising. For instance, there is a link between maternal licking of male rat pups and their ability to perform sexually as adults (Moore 1992). From these examples, one gets the impression that cryptic environmental influences abound and that the only obstacle to their discovery is researchers’ ability to anticipate them. However, if researchers are often unaware of which environmental factors influence a trait, they then are unlikely to test for those factors experimentally. This means that traits will be deemed “innate” or environmentally canalized, not because they are buffered against many environmental factors, but rather because researchers have not thought to look at the factors to which they are sensitive.