Cat intelligence study is mostly from consideration of the domesticated cat. The process of domestication has allowed for closer observation of cat behaviour and in the increased incidence of interspecies communication, and the inherent plasticity of the cat's brain has become apparent as the number of studies in this have increased scientific insight. Changes in the genetic structure of a number of cats have been identified as a consequence of both domestication practises and the activity of breeding, so that the species has undergone genetic evolutionary change due to human selection (although this human selection has been coupled with an initial naturally occurring selective set of cats possessing characteristics desirable for the sharing of human habitation and living in Neolithic urban environments).