Coyne and the Meaning of Evolution: Why Darwinism Is False, Part II - Evolution News & Views

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Coyne and the Meaning of Evolution: Why Darwinism Is False, Part II

Read Part I here

Jerry A. Coyne is a professor in the Department of Ecology and Evolution at The University of Chicago. In Why Evolution Is True, he summarizes Darwinism--the modern theory of evolution--as follows: "Life on earth evolved gradually beginning with one primitive species--perhaps a self-replicating molecule--that lived more than 3.5 billion years ago; it then branched out over time, throwing off many new and diverse species; and the mechanism for most (but not all) of evolutionary change is natural selection." 1

Coyne further explains that evolution "simply means that a species undergoes genetic change over time. That is, over many generations a species can evolve into something quite different, and those differences are based on changes in the DNA, which originate as mutations. The species of animals and plants living today weren't around in the past, but are descended from those that lived earlier."2

According to Coyne, however, "if evolution meant only gradual genetic change within a species, we'd have only one species today--a single highly evolved descendant of the first species. Yet we have many... How does this diversity arise from one ancestral form?" It arises because of "splitting, or, more accurately, speciation," which "simply means the evolution of different groups that can't interbreed."3

If Darwinian theory were true, "we should be able to find some cases of speciation in the fossil record, with one line of descent dividing into two or more. And we should be able to find new species forming in the wild." Furthermore, "we should be able to find examples of species that link together major groups suspected to have common ancestry, like birds with reptiles and fish with amphibians." Finally, there are facts that "make sense only in light of the theory of evolution" but do not make sense in the light of creation or design. These include "patterns of species distribution on the earth's surface, peculiarities of how organisms develop from embryos, and the existence of vestigial features that are of no apparent use." Coyne concludes his introduction with the bold statement that "all the evidence--both old and new--leads ineluctably to the conclusion that evolution is true."4

Of course, "evolution" is undeniably true if it means simply that existing species can change in minor ways over time, or that many species living today did not exist in the past. But Darwin's claim that all species are modified descendants of a common ancestor, and Coyne's claim that DNA mutations and natural selection have produced those modifications, are not so undeniably true. Coyne devotes the remainder of his book to providing evidence for them.

Fossils
Coyne turns first to the fossil record. "We should be able," he writes, "to find some evidence for evolutionary change in the fossil record. The deepest (and oldest) layers of rock would contain the fossils of more primitive species, and some fossils should become more complex as the layers of rock become younger, with organisms resembling present-day species found in the most recent layers. And we should be able to see some species changing over time, forming lineages showing 'descent with modification' (adaptation)." In particular, "later species should have traits that make them look like the descendants of earlier ones."5

In The Origin of Species, Charles Darwin acknowledged that the fossil record presented difficulties for his theory. "By the theory of natural selection," he wrote, "all living species have been connected with the parent-species of each genus, by differences not greater than we see between the natural and domestic varieties of the same species at the present day." Thus in the past "the number of intermediate and transitional links, between all living and extinct species, must have been inconceivably great." But Darwin knew that the major animal groups--which modern biologists call "phyla"--appeared fully formed in what were at the time the earliest known fossil-bearing rocks, deposited during a geological period known as the Cambrian. He considered this a "serious" difficulty for his theory, since "if the theory be true, it is indisputable that before the lowest Cambrian stratum was deposited long periods elapsed... and that during these vast periods the world swarmed with living creatures." And "to the question why we do not find rich fossiliferous deposits belonging to these assumed earliest periods prior to the Cambrian system, I can give no satisfactory answer." So "the case at present must remain inexplicable; and may be truly urged as a valid argument against the views here entertained."6

Darwin defended his theory by citing the imperfection of the geological record. In particular, he argued that Precambrian fossils had been destroyed by heat, pressure, and erosion. Some of Darwin's modern followers have likewise argued that Precambrian fossils existed but were later destroyed, or that Precambrian organisms were too small or too soft to have fossilized in the first place. Since 1859, however, paleontologists have discovered many Precambrian fossils, many of them microscopic or soft-bodied. As American paleobiologist William Schopf wrote in 1994, "The long-held notion that Precambrian organisms must have been too small or too delicate to have been preserved in geological materials... [is] now recognized as incorrect." If anything, the abrupt appearance of the major animal phyla about 540 million years ago--which modern biologists call "the Cambrian explosion" or "biology's Big Bang"--is better documented now than in Darwin's time. According to Berkeley paleontologist James Valentine and his colleagues, the "explosion is real, it is too big to be masked by flaws in the fossil record." Indeed, as more fossils are discovered it becomes clear that the Cambrian explosion was "even more abrupt and extensive than previously envisioned."7

What does Coyne's book have to say about this?

"Around 600 million years ago," Coyne writes, "a whole gamut of relatively simple but multicelled organisms arise, including worms, jellyfish, and sponges. These groups diversify over the next several million years, with terrestrial plants and tetrapods (four-legged animals, the earliest of which were lobe-finned fish) appearing about 400 million years ago."8

In other words, Coyne's account of evolutionary history jumps from 600 to 400 million years ago without mentioning the 540 million year-old Cambrian explosion. In this respect, Coyne's book reads like a modern biology textbook that has been written to indoctrinate students in Darwinian evolution rather than provide them with the facts.

More on Coyne tomorrow.

Notes
1 Jerry A. Coyne, Why Evolution Is True (New York: Viking, 2009), p. 3.
2 Coyne, Why Evolution Is True, pp. 3-4.
3 Coyne, Why Evolution Is True, pp. 5-6.
4 Coyne, Why Evolution Is True, pp. 18-19.
5 Coyne, Why Evolution Is True, pp. 17-18, 25.
6 Charles Darwin, The Origin of Species, Sixth Edition (London: John Murray, 1872), Chapter X, pp. 266, 285-288. Available online (2009) here.
7 J. William Schopf, "The early evolution of life: solution to Darwin's dilemma," Trends in Ecology and Evolution 9 (1994): 375-377.
James W. Valentine, Stanley M. Awramik, Philip W. Signor & M. Sadler, "The Biological Explosion at the Precambrian-Cambrian Boundary," Evolutionary Biology 25 (1991): 279-356.
James W. Valentine & Douglas H. Erwin, "Interpreting Great Developmental Experiments: The Fossil Record," pp. 71-107 in Rudolf A. Raff & Elizabeth C. Raff, (editors), Development as an Evolutionary Process (New York: Alan R. Liss, 1987).
Jeffrey S. Levinton, "The Big Bang of Animal Evolution," Scientific American 267 (November, 1992): 84-91.
"The Scientific Controversy Over the Cambrian Explosion," Discovery Institute. Available online (2009) here.
Jonathan Wells, Icons of Evolution (Washington, DC: Regnery Publishing, 2002), Chapter 3. More information available online (2009) here.
Stephen C. Meyer, "The Cambrian Explosion: Biology's Big Bang," pp. 323-402 in John Angus Campbell & Stephen C. Meyer (editors), Darwinism, Design, and Public Education (East Lansing, MI: Michigan State University Press, 2003). More information available online (2009) here.
8 Coyne, Why Evolution Is True, p. 28.