Assertion 4.17: Regardless of mutation rates, the rate of microevolution is too low to account for the macroevolutionary change observed in the fossil record.
Analysis:
Philip D. Gingerich makes a few observations about this point, using the "darwin" (d) as a factor of change (1 d = change by a factor of e per million years, e being the base of the natural logarithm: see Gingerich 1983:159):
[R]ates [of evolution] on the order of 400 d probably characterize speciation and radiation in new adaptive zones...Microevolutionary rates measured on the scale of tens or hundreds of years are much higher than phyletic rates derived from fossils. A microevolutionary rate of 400 d is sufficient to change a mouse into an elephant in 10,000 years...Evolution on a microevolutionary scale is invisible in the fossil record, but this does not preclude microevolutionary processes operating over geological time from producing macroevolutionary change on the longer time scale. Microevolution and macroevolution are different manifestations of a common underlying process. (Gingerich 1983:161).
References
Gingerich PD. 1983. Rates of evolution: effects of time and temporal scaling. Science 222:159-161.
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