Intelligent Design advocates have long asserted that while microevolution may occur resulting in minor changes within species, only an intelligent designer can make major changes that result in new species or body types. However, cultural anthropologist David Eller argues in Skeptic magazine that this notion of 'micro-creation' fails on two levels: it neither strengthens the case for 'macro-creationism' nor does it weaken the case for macroevolution.
A STANDARD TACTIC USED by creationists to attack evolution is to contrast microevolution (i.e., within species evolution, which they accept) with macroevolution (i.e., between species evolution, which they adamantly reject). Microevolution, they grant, may or does occur. But they assert that macroevolution either has never been observed or is theoretically impossible. They argue that while microevolution may be true, it is trivial, and the major claim of evolution — the evolution and emergence of species — is either unsubstantiated or false.
This failure to account for macrophenomena, such as human life, the earth, or the universe, then serves as an opportunity to suggest that creation is the only plausible alternative for the origin of life. This conclusion suffers from the fallacy of the excluded middle or false dilemma (just because B is false does not make A true). But ironically the “success” of the “scientific” creationist enterprise, particularly its most recent and “serious” incarnation — Intelligent Design (ID) — has itself up to this point rested on claims regarding a few minor fragmentary subspecies processes rather than the macroprocesses that it is so keen to deny to evolution.
[I]n the end, microevolution is nothing more than descent with modification over the short term, and macroevolution is descent with modification over the long term. Put another way, macroevolution is merely the accumulation of microevolutionary changes. The only difference between them is time-scale. The same thing cannot be said about microcreation and macrocreation. Macrocreation is not the accumulation of microcreationist events; if it were, then macrocreation would be “blind” or incidental. You do not get a flagellum over the short term and a protist over the long term. Where would the flagellum reside in the meantime? We can conclude with confidence that microcreation fails as an explanation even of microlevel phenomena and that, even if it were it to succeed at that level, it would still fail as a ground for macrocreation.