Re: [asa] Dawkins on the fossil record

From: John Walley <john_walley@yahoo.com>
Date: Tue Dec 15 2009 - 17:56:17 EST

I found this at  http://www.space.edu/documents/Volcanoclimate.pdf Presciently, Humphreys had already speculated in his 1913 paper the possibility that sustained volcanic activity might trigger Ice Ages. Developing this further, Stanley Ambrose has proposed that the Toba volcanic winter brought widespread famine and death to human populations around the world. This abrupt "bottleneck" in population, is thought to have favoured evolutionary changes, which occur much faster in small populations, to produce rapid population differentiation of modern human races only 70,000 years ago. ________________________________ From: dfsiemensjr <dfsiemensjr@juno.com> To: Dennis.Venema@twu.ca Cc: john_walley@yahoo.com; bernie.dehler@intel.com; asa@calvin.edu Sent: Tue, December 15, 2009 5:32:52 PM Subject: Re: [asa] Dawkins on the fossil record I'm sorry that I can't give you a citation, but the bottleneck in the human past comes from comparing human and chimp genomes. The latter have a much greater number of variants in a currently smaller population, indicating a population continuity extending back many (millions ?) of years. The number of variants in all humans tested is much smaller, indicating that perhaps 50,000 years or so ago there was only a small group of survivors. I recall one suggestion that the volcanic eruptions that produced the Deccan traps may have been responsible for the near extinction. I can only report what I've encountered, not evaluate it. Dave(ASA) On Tue, 15 Dec 2009 12:12:19 -0800 Dennis Venema <Dennis.Venema@twu.ca> writes: I’m not sure where David is getting his information from. I have seen no evidence to suggest a population bottleneck all the way back to the human – chimp – gorilla common ancestor (population). > >Dennis > ____________________________________________________________ Bad Credit Loan Need cash? Apply now for a credit loan with fast approval.

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