by MonteQuest » Sun 28 Aug 2005, 04:26:39
Well, what you are referring to here is called “punctuated equilibrium.” Punctuated equilibrium is more an observation of catastrophic events and a steady state, rather than a theory of evolution. When we study the fossils of organisms found in subsequent geological formations we see long intervals in which nothing changed followed by short, radical transitions, in which species became extinct and were replaced by entirely new forms.
In fact, the origins of this theory are rooted in Darwin’s writings in The Origin of Species:
$this->bbcode_second_pass_quote('', '')The periods during which species have undergone modification, though long as measured in years, have probably been short in comparison with the periods during which they retain the same form."
$this->bbcode_second_pass_quote('', '')But I must here remark that I do not suppose that the process ever goes on so regularly as is represented in the diagram, though in itself made somewhat irregular, nor that it goes on continuously; it is far more probable that each form remains for long periods unaltered, and then again undergoes modification.”
$this->bbcode_second_pass_quote('', '')Although isolation is of great importance in the production of new species, on the whole I am inclined to believe that largeness of area is still more important, especially for the production of species which shall prove capable of enduring for a long period, and of spreading widely."