Phyletic gradualism has been largely deprecated as the exclusive pattern of evolution by modern evolutionary biologists in favor of the acceptation of occurrence of patterns such as those described on punctuated equilibrium, quantum evolution, and punctuated gradualism.
Authors such as Richard Dawkins argue that such constant-rate gradualism is not present in academic literature, serving only as a straw-man for punctuated equilibrium advocates. He refutes the idea that Charles Darwin himself was a constant-rate gradualist, as suggested by Stephen Jay Gould, for Darwin has explicitly stated that "Many species, once formed, never undergo any further change...; and the periods, during which species have undergone modification, though long as measured by years, have probably been short in comparison with the periods during which they retain the same form."
The theory of the punctuated equilibrium goes against the theory of phyletic gradualism.
Greenwood, Rosen, Weitzman, and Myers: Circumstances Surrounding the Publication of "Phyletic Studies of Teleostean Fishes, with a Provisional Classification of Living Forms," 1966
Dec 27, 2011; IN 1966, four of the world's leading ichthyologists (Fig. 1), Peter Humphry Greenwood (1927-1995) of the British Museum of...
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