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Author Topic:   Question About Evolutionary Rates
Dr Adequate
Member (Idle past 284 days)
Posts: 16113
Joined: 07-20-2006


Message 1 of 4 (409041)
07-06-2007 11:01 PM


Hi. One for the biologists, if they can help me out.
Suppose we have a set of selection pressures on a lineage, each of which would favor a novel mutation, and which do not interfere with one another: i.e. if selection pressure A favors mutation A, and selection pressure B favors mutation B, then the two selection pressures acting simultaneously will favor mutations A and B; and such that for all A and B the selective advantage of mutation A, when selection pressure A is operating, is the same whether or not selection pressure B is operating. We might call such pressures "orthogonal".
Suppose we do two experiments:
(1) We apply these selection pressures one at a time, and wait for each mutation to arise and be fixed before introducing a new pressure. So we apply selection pressure A, wait for mutation A to arise and be fixed in the gene pool, then apply pressures A and B, wait for mutation B to arise and be fixed in the gene pool, then apply pressures A, B and C ... and so forth until all the mutations have arisen and are fixed.
(2) Apply all the pressures simultaneously and wait until all the mutations have arisen and are fixed.
Suppose further that we can do this in such a way that the population is constant and the same in both experiments.
Which should go quicker?
I say that the second experiment should finish more quickly: this follows from probability theory and is borne out by computer simulations.
What I do not know is whether anyone has ever tried this out in real life. If anyone can help, I should be most grateful.
Edited by Dr Adequate, : No reason given.

Replies to this message:
 Message 2 by Adminnemooseus, posted 07-06-2007 11:21 PM Dr Adequate has replied

Adminnemooseus
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Message 2 of 4 (409045)
07-06-2007 11:21 PM
Reply to: Message 1 by Dr Adequate
07-06-2007 11:01 PM


Start with, how about a better topic title?
Something more tailored to the content of message 1.
That said, I'm passing this one to one of out bioadmins.
Adminnemooseus

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This message is a reply to:
 Message 1 by Dr Adequate, posted 07-06-2007 11:01 PM Dr Adequate has replied

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 Message 3 by Dr Adequate, posted 07-07-2007 12:01 AM Adminnemooseus has not replied

Dr Adequate
Member (Idle past 284 days)
Posts: 16113
Joined: 07-20-2006


Message 3 of 4 (409049)
07-07-2007 12:01 AM
Reply to: Message 2 by Adminnemooseus
07-06-2007 11:21 PM


Re: Start with, how about a better topic title?
It's kind of a difficult question to summarize, I'm afraid. Have you any suggestions?

This message is a reply to:
 Message 2 by Adminnemooseus, posted 07-06-2007 11:21 PM Adminnemooseus has not replied

Admin
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Message 4 of 4 (410313)
07-14-2007 9:39 AM


Thread copied to the Question About Evolutionary Rates thread in the Biological Evolution forum, this copy of the thread has been closed.

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