[PatrickHenry]

For a description of how new mutations enter the population and eventually lead to speciation without there ever being a point where an individual has a problem mating with the members of the population to which he/she belongs, see this.

You might also try this. Not as authoritative as Ichneumon, but it's readable.

[thomaswest]

http://www.freerepublic.com/~patrickhenry/#herd

Very well-written, clear, and persuasive.

Well done!