From Slate:
Even identical twins brought up in similar environments won’t really be identical. They won’t have the same fingerprints. They’ll have different freckles and moles. Even complex traits such as intelligence and mental illness often vary between identical twins. Of course, some of this variation is due to environmental factors. … But there is more to the story. There is a third factor, crucial to development and behavior, that biologists overlooked until just the past few decades: random noise. … Cailin O’Connor is an assistant professor of logic and philosophy of science at the University of California, Irvine.

For the full post, please visit http://www.slate.com/articles/health_and_science/science/2014/09/random_....