In article <Pine.SOL.3.91.950414173342.20428A-100000 at corona> Patrick
O'Neil, patrick at corona writes:
>> I know there are several people who have published papers
>> argueing that the "molecular clock rate" of different organisms varies
as
>> a function of reproductive time. That animals such as rodents with a
1
>> or 2 month period between generations have a faster molecular clock
than
>> do primates with generation times of 3 to 30 years.
>> I could not find any references at my fingertips (no MedLine
>>I would think that generation _time_ would be rather irrelevant (Unless
>your generation time is a million years :) ). I would think that the
>fact that mice have a less efficient DNA damage repair system than
humans
>do, for instance, and so THIS would lead to a higher "clock rate" for
>them vs us, that is, sequence variations will occur at a higher rate per
>replication. Correcting for more rapid generation time, the mutation
>rate should itself be more important.
Mutations that occur during DNA replication will only be accumulated in
the
lineage if they are present in the gametes. A shorter generation time will
present a greater chance of a mistake in DNA replication occuring in a
sex cell
that goes on to form a new organism.
For references try:
Chao, L., & Carr, D. E. (1993) Evolution 47:668-690.
Martin, A. P., & Palumbi, S. R. (1993) Proc. Natl. Acad. Sci. USA
90:4087-4091
Mooers, A. O., & Harvey, P. H. (1994) Molecular Phylogenies and Evolution
3:344-350
=====================================================================
Andrew Rambaut,
Zoology Department, EMAIL - Andrew.Rambaut at zoology.ox.ac.uk
University of Oxford,
South Parks Road, Oxford, England.
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