Below, a lesser light paraphrases a more detailed treatment in a book by Schopf.
http://www.freerepublic.com/forum/a3a535d71403d.htm#111.
A point on sexual versus asexual (from the introductory year in which the online Britannica was a free site):
Why do I keep catching crap like this from people who obviously know better?
The answer to that question is the answer to all the others. Why not "teach the controversy?" Why not "teach both theories?" Why not teach the valid "alternatives" (and / or "the valid objections") to evolution?
The only controversy is outside of science, so the controversy does not belong in science class. (Unless perhaps we spend some little time teaching the kids how to tell crackpot presentations from serious science, in which case there's exactly that much room for analysis of creationist claims.) There is only one reasonably tight scientific hypothesis square with the evidence and it isn't creation or ID. There are no alternatives and no objections which are reasonable or even honest.