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Science Frontiers ONLINE No. 19: Jan-Feb 1982 |
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Species Stability Is A Real Problem
The reader should refer to the following item for the basic paleontological facts discussed by Williamson. The biological implications of the mollusc lineages drawn up by Willianson are rather profound. In the present item, Williamson complains that scientists and critics have focussed primarily upon his claim that his mollusc lineages support the punctuated evolution model (which they do) but avoid his main point: namely, that the lineages are static over very long periods of time. They do not change slowly, bit by morphological bit, into new species as an evolutionist would expect. Instead, they remain un-changed until they become extinct. This striking aspect of the fossil record is not predicted by neo-Darwinism -- and there is the rub!
(Williamson, Peter G.; "Morphological Stasis and Developmental Constraint: Real Problems for Neo-Darwinism," Nature, 294:214, 1981.) Comment. In neo-Darwinism, evolution unfolds by small accumulated changes, the causes of which may be chemicals in the environment, nuclear radiation, and other "stresses." Neo-Darwinism goes hand-in-hand with geological Uniformitarianism, both of which are favored philosophically by scientists because slow change is more amenable to scientific explanation. The large sidewise steps of punctuated evolution are difficult to explain in terms of known "forces." In this context, the radical concepts of directed panspermia and the impact of viruses on evolution may be important!