Biological DiscontinuityEvolution is committed to continuity in a broad sense. Its main business is to connect dots. But for dots to be plausibly connected, they need to be reasonably close together. That's why the absence of transitional forms, gaps, and missing links or intermediates constitute a problem for evolution. To be sure, evolutionists do not regard the absence of intermediates as a problem in the bad sense. They regard such discontinuities not as challenges to their theory but as discontinuities that are only apparent and that will disappear once the missing intermediates are found. Consequently, whenever an intermediate is found, it is regarded as a triumph for evolutionary theory (witness the recent excitement over the Toumaļ fossil find in Chad).
Evolutionary biology attempts to explain the absence of intermediates from an evolutionary path on the assumption that the intermediates did once exist. But now let’s turn the question around. Suppose that discontinuity is a fact not just about the history of life as we know it but about the history of life itself—in other words, the intermediates never existed. In that case, how did biological forms in all their vast complexity and diversity come about? In asking this question, let's hold off asking for the underlying cause or causes of biological complexity and diversity. Rather, let's merely ask what a video camera would see if it were scouring the past and recording key events in life’s history. There are exactly four possibilities:
(1) Nonbiogenic emergence. Organisms emerge without the direct causal agency of other organisms. In place of life begetting life, here we have nonlife begetting life.
(2) Generative transmutation. Organisms, in reproducing, produce offspring that are vastly different from themselves.
(3) Biogenic reinvention. Organisms reinvent themselves in midstream. At one moment they have certain morphological and genetic features, at the next they have a vastly different set of such features.
(4) Symbiogenic reorganization. Organisms emerge when different organisms from different species get together and reorganize themselves into a new organism.
None of these possibilities is out to lunch. Nonbiogenic emergence had to happen at least once, namely, at the origin of life. Symbiogenic reorganization has been Lynn Margulis's main focus of research, and there is increasing evidence for it. Biogenic reinvention (organisms changing in midstream) is also not that crazy when one considers the life cycles of certain organisms which from one stage to the next are completely unrecognizable (for example, the metamorphosis of the butterfly or, even more extremely, the various forms of the liver fluke). Finally generative transmutation suggests a programmed view of evolution, where, like a computer program that kicks in at a certain time (recall the Michelangelo virus that kicked in March 6th, 1993), organisms change in one generation. French paleontologist Anne Dambricourt has seriously argued for this view in respect to the emergence of Homo sapiens.
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