Post date: Mar 29, 2010 10:7:19 AM
Of course, there is no question that natural selection plays a key role in evolution. Darwin made a convincing case a century and a half ago in On the Origin of Species, and countless subsequent studies support his ideas. But there is an irony in Darwin's choice of title: his book did not explore what actually triggers the formation of a new species. Others have since grappled with the problem of how one species becomes two, and with the benefit of genetic insight, which Darwin lacked, you might think they would have cracked it. Not so. Speciation still remains one of the biggest mysteries in evolutionary biology.
New Scientist 10/03/2010
http://www.newscientist.com/article/mg20527511.400-accidental-origins-where-species-come-from.html