The stratigraphic phenomena would be observed from 1) morphological stasis in a large population 2) an unrecorded founder event to a peripherally isolated population 3) speciation , perhaps through a "genetic revolution", where a new equilibrium morphology would be assumed and 4) Range expansion of this new form back into the range of the original form (see diagram below). These events, entirely consistent with "Darwinian" or "Modern Synthesis" phenomena, would be observed as a punctuational pattern (see fig. below). Note that there are other sequences of events that might give rise to the punctuational pattern. Several questions arise: 1) What is rapid ? 10,000 - 100,000 years can be an instant in geological time (especially in the context of some deposition rates) but is ample time for evolutionary events in populations. Recall that the shift from the peppered to the dark form of Biston betularia occured within the span of 100 years by a completely "Darwinian" mechanism. 2) Is
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This note was uploaded on 11/06/2011 for the course BIO BSC1010 taught by Professor Gwenhauner during the Fall '10 term at Broward College.