Assertion 7.4: There are many theories of evolution, each of which disproves the others.
Analysis:
(i) According to the late evolutionary biologist Ernst Mayr, the five major elements of Darwinian theory are:
The notion that organisms transformed over time.
The common descent of all organisms.
The multiplication of species through speciation.
Gradual as opposed to saltationary change of populations.
Natural selection as the driving force behind the change (Mayr 1991:36-37)
All evolutionists, whether gradualists, punctuationalists, or whatever, understand and accept the first three elements. There is indeed disagreement about the fourth and fifth elements, but all sides recognize that the evidence for the first three is conclusive, regardless of what one believes about the mechanisms and tempo of evolution. As it turns out, the second element is the central issue in the evolution vs. creationism debate, so the debate between evolutionists over the fourth and fifth elements does not help creationism at all, and is not a sign of weakness in evolutionary theory.
(ii) With respect to the alleged conflict between punctuationalism and Darwinism specifically, it is helpful to note that the current consensus is that there is in fact no conflict. Evolutionary biologist Michael Rose explains:
With time, the controversy [between punctuationalism and Darwinian gradualism] diffused. Population geneticists showed that even gradual selection within populations could produce evolutionary change that would appear virtually instantaneous on a geological time-scale, such as that defined by the fossil record. [Punctuationalist Stephen Jay] Gould backed away from some of his flirtations with non-Darwinian evolution. The main people who felt that something big had really happened were the editors who put together cover stories for popular magazines, as well as the rabble of anti-Darwinians, including creationists, who are so often happy to celebrate confusion among the Darwinians.
The consensus now is pretty much where Darwin was. We expect evolution to be sedate in biological time, but its results can be fairly abrupt and disjointed in the fossil record. (Rose 1998:88-89)
(iii) If the multiplicity of theories of evolutionary mechanisms can be though to pose a problem for the greater theoretical framework of evolution, then the creationists are in much worse trouble than the evolutionists, as there are far more creationist theories than evolutionist ones. To name a few within the Judeo-Christian tradition, there are:
Day/age creationists such as the Jehovah's Witnesses, who believe that each "day" in Genesis 1 represents millennia.
Gap theorists who follow the Scofield Reference Bible in asserting that there were two creations: the first one being described in verse 1:1 of Genesis, and involving all of the extinct life now found in the fossil record, and the second one being described in the later verses of Genesis, and involving the life forms that are alive today.
Progressive creationists who believe in "a series of numerous separate creations, each interrupted by a gap in the fossil record" (Edwords 1983:305).
Special creationists such as the famous members of the Institute for Creation Research, who hold that all life was created in six 24-hour periods around 6,000 years ago, and that the Noachian Flood is responsible for everything from the fossil record to radiometric dates.
There are also individual creationists who do not fit neatly into any these four categories. For example, consider Michael Behe - despite being one of the most trenchant modern critics of Darwinism, and despite believing that a creator must have had a hand in the origin of certain specific molecular structures and processes (for instance, in bacterial flagella, but not in hemoglobin), nevertheless openly acknowledges his belief in common descent:
I find the idea of common descent (that all organisms share a common ancestry) fairly convincing, and have no particular reason to doubt it. I greatly respect the work of my colleagues who study the development and behavior of organisms within an evolutionary framework, and I think that evolutionary biologists have contributed enormously to our understanding of the world. (Behe 1996:5)
As reported by cell biologist Kenneth R. Miller, Behe does not share even the primary quarrel of most creationists, namely the common descent of humans and the great apes:
In a 1995 debate, I presented [Behe] with molecular evidence indicating that humans and the great apes shared a recent, common ancestor, wondering how he would refute the obvious. Without skipping a beat, he pronounced the evidence to be convincing, and stated categorically that he had absolutely no problem with the common ancestry of humans and great apes. Creationists around the room - who had viewed him as their new champion - were dismayed. (Miller 1999:164)
It is worth noting, finally, that all of the above are only a sample of Christian varieties of creationism. There are other religions with their own creation stories and their own "creation scientists."
References
Behe M. 1996. Darwin's Black Box: The Biochemical Challenge of Evolution. New York: Free Press.
Edwords F. 1983. Is it really fair to give creationism equal time? In Godfrey 1983:11-32.
Mayr E. 1991. One Long Argument. Cambridge: Harvard University Press.
Miller KR. 1999. Finding Darwin's God: A Scientist's Search for Common Ground Between God and Evolution. New York: Cliff Street Books.
Rose MR. 1998. Darwin's Spectre: Evolutionary Biology in the Modern World. Princeton: Princeton University Press.
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