<P> At the other extreme, traits such as native language are environmentally determined: linguists have found that any child (if capable of learning a language at all) can learn any human language with equal facility . With virtually all biological and psychological traits, however, genes and environment work in concert, communicating back and forth to create the individual . </P> <P> At a molecular level, genes interact with signals from other genes and from the environment . While there are many thousands of single - gene - locus traits, so - called complex traits are due to the additive effects of many (often hundreds) of small gene effects . A good example of this is height, where variance appears to be spread across many hundreds of loci . </P> <P> Extreme genetic or environmental conditions can predominate in rare circumstances--if a child is born mute due to a genetic mutation, it will not learn to speak any language regardless of the environment; similarly, someone who is practically certain to eventually develop Huntington's disease according to their genotype may die in an unrelated accident (an environmental event) long before the disease will manifest itself . </P> <P> Steven Pinker likewise described several examples: </P>

Where did the nature vs nurture debate start