Darwin's Dangerous Idea

The purpose of this review is to draw attention to the extraordinary significance of "Darwin's Dangerous Idea" by Daniel Dennett and "River Out Of Eden" by Richard Dawkins. Each, in its own different way, gives an idea of the extraordinary scope and subtlety of the modern theory of evolution. Without such understanding, evolution is ideology rather than science.

Due to the scientific revolution of the 17th century the mystery of the cosmos was solved to everyone's satisfaction. It took longer to make headway with the mystery of life. By this I mean the phenomenon of "the herb yielding seed and the fruit tree yielding fruit after his kind" (Genesis 1:11).

In the late 18th century, when people had stopped believing in a stationary Earth at the centre of the universe, scientists used "evolution" to mean the family resemblances among biological species and the tendency of more complex lifeforms to appear later in the geological record. A well-known writer of that period was Jean-Baptiste Lamarck, who explained adapted characteristics, such as the long necks of giraffes, to have evolved through more intensive use by individuals that were more successful in reproduction.

In 1859 Charles Darwin published "The Origin of Species", a book that proposed an additional mechanism for evolution, namely natural selection. Why was this book a bombshell, whereas Lamarck's "Philosophie zoologique, ou Exposition des considérations relatives à l'histoire naturelle des animaux" (1809) was not? After all, Lamarck's theory was just as incompatible with the Biblical account of creation. Perhaps it was that Darwin's title "The Origin of Species" is an easily recognizable version of "The Creation of Kinds", which calls to mind Genesis chapter 1, verse 11. Or perhaps another fifty years of science had intensified the desire for an alternative to Genesis.

Did Darwin understand the theory of evolution?

Darwin thought that heritable traits are a result of use and disuse and that features acquired during an organism's lifetime could be passed on to its offspring. He thought of examples, such as large ground-feeding birds developing stronger legs through use, and weaker wings from not flying until, like in the ostrich, the ability to fly is lost.

The correctness, or otherwise, of this idea is independent of the distinct idea that the combination of limited resources and the fact that a superior trait gives rises to growth in a geometrical progression results in this trait establishing itself in a biological population. It is this distinct idea that is original with Darwin, and is called "natural selection". Dennett shows that this idea not only explains much in biology, but is also applicable elsewhere. This is why Dennett considers it a dangerous idea.

As published, Darwin's theory was indefensible. Its defect is that, for all one could see at the time, the random modifications that occur in descendants would revert to the original in succeeding generations. The miracle of Darwin's theory is that, as more was discovered in science, it became more believable. Important steps: discovery of the gene, mathematical work, and the understanding that it is the gene pool that characterizes the species and evolves, rather than individuals.

The gene was first discovered by Mendel during Darwin's lifetime, but Mendel's work remained unknown until it was discovered soon after 1900 by Bateson, by de Vries, and by Tschermak. The mathematical work was started by Haldane, by Fisher, and by Wright in the 1920's. The structure of DNA was discovered in the 1950's and elucidated the properties of the gene. The unravelling of the genetic code in the 1960's explained why characteristics of an individual acquired during its lifetime are not passed on to its offspring. All these 20th-century developments coalesced into what is called the "modern synthesis" in evolutionary theory.

Thus, after Darwin gave the initial push with his "Origin of Species" in 1859, nothing happened on the scientific front for half a century. Darwin didn't have a theory of evolution, nor did any of his numerous adherents. After another half century the modern synthesis had gelled into a large body of knowledge of fiendish subtlety. The books by Dennett and by Dawkins give the outsider a good idea of this.

Did Scopes understand the theory of evolution?

Scopes? I mean John Scopes, he of the Scopes trial, that bizarre event which was the trial in which Scopes was accused of violating the state of Tennessee's Butler Act. This act had made it unlawful to teach human evolution in any state-funded school. I characterized the trial as a "bizarre event" because the trial took place in 1925, when the beginnings of the modern synthesis were tentatively forming in the minds of a few of the most advanced thinkers. The idea of the teaching of evolution by high-school teachers to high-school students was at the time not science instruction, but ideological indoctrination.

The Scopes trial was just the beginning

The Scopes trial was only the opening salvo in court battles for at least eighty years. Epperson v. Arkansas, is a 1968 Supreme Court case that invalidated an Arkansas statute that prohibited the teaching of human evolution in the public schools. McLean v. Arkansas Board of Education is a 1981 legal case in the state of Arkansas. A lawsuit was filed by various parties who argued that the Arkansas state law known as the "Balanced Treatment for Creation-Science and Evolution-Science Act" was unconstitutional. Edwards v. Aguillard is a 1987 Supreme Court case concerning a Luisiana statute with similar intent. In 2005 the Dover Area School District was sued over the school board requirement that a statement presenting Intelligent Design as "an explanation of the origin of life that differs from Darwin's view" was to be read aloud in ninth-grade science classes when evolution was taught.

I want to leave the rulings in these cases to the reader. Nor is my opinion on these cases relevant. What matters is that teaching evolution in high school is not science instruction. Only with the Modern Synthesis has the theory of evolution become science. It is rare for a high-school teacher to understand this. Only students with a few years of study in genetics and statistics can be meaningful recipients of teaching in the theory of evolution and then only when the teacher has a special interest in the theory.

The Supreme Court rulings are on the right track: religion must not be taught in publicly funded secondary schools. But not just religion should be so proscribed, but all forms of ideology. And the teaching of evolution in high school is a form of ideology.