Darwin was right
She has her mother’s eyes. He has his father’s nose. We expect kids to look like their parents, and we aren’t surprised when physical traits are passed from parents to offspring.
Most of us have never seen a gene, but we don’t question their existence. Scientists publish studies linking specific genes to certain types of cancer or other diseases. We listen to the reports and consider them facts, even if we don’t always change our behavior in response to new information. We are convinced by the evidence.
In fact, most mainstream scientific theories are widely accepted by the public—with one notable exception. Since long before the Scopes “Monkey Trial” of 1925, in which biology teacher John Scopes was convicted of teaching that humans evolved from ancestor species rather than being specially created by God, the scientific understanding of evolution has been attacked in heated public arguments by proponents of creationism. Even as evidence of evolution piles up in the scientific literature, the intense public debate remains, 150 years after the first publication of the core of evolutionary theory, Charles Darwin’s On the Origin of Species.
But the available evidence fully supports evolution. In Why Evolution Is True, Jerry A. Coyne boils down this evidence to its essence in a concise, readable discussion. Why people have an appendix, why mammals and amphibians are found on some islands but not others and why some mice have dark coats while others are lighter in color—all of these are easily accounted for by evolution and cannot be logically explained without it.
Coyne bluntly states what should be obvious, yet is too often overlooked: Not a single version of creationism—including recent variants such as “intelligent design”—is scientific. All versions of creationism rely on some supernatural intervention. Take away the religious stories—the supernatural element—and there is no creationism theory. Coyne flatly states, “You can find religions without creationism, but you never find creationism without religion.”
Although scientists may disagree on some details of how evolution occurs, there is no disagreement in the scientific community over the fact that it does occur. Coyne breaks down the present understanding of evolution into its basic components: Genetic changes occur in a species over many generations, resulting in new species that evolved from common ancestors. Evolution is driven by both natural selection and nonselective mechanisms, with natural selection acting on characteristics that affect an organism’s ability to produce offspring. Characteristics that don’t keep us from having lots of kids (who in turn go on to reproduce), like a tendency toward heart disease later in life, are not subject to natural selection.
Evolution does not have to proceed by a single gene or attribute at a time. Nor has it advanced in a straight line, with fishes changing into salamanders, which in turn changed into mice, monkeys and humans. Instead of seeing a fossil record full of holes and missing links, scientists see related species that evolved from common ancestors, even if the ancestors themselves left no record for us.
What about those gaps in the fossil record? Coyne explains—perhaps too briefly, considering its importance in his argument—the difficult process in creating a fossil. Conditions must be just right for dead animal and plant tissue to be fossilized. Then conditions must also be right for us to find fossils all these millennia later.
Why Evolution Is True is written in a straightforward style that is appropriate to its no-nonsense title. Coyne makes the case for evolution effectively, and directed at the literate nonscientist. He convincingly presents the evidence for why evolution is truly mainstream science.