But perhaps it isn't. Predation by human consumption of human food species is shown to phenotypically change the species fairly rapidly.... this fits Reznick's guppies and other similar studies into epigenetics. Funny but epigenetics is not discussed in this article on 'unnatural selection', a study on the issue of the need to change harvesting techniques:-http://www.nature.com/nature/journal/v457/n7231/full/457803a.html