Darwin’s Theory: Science or myth?

"Darwin thought that the study of embryological development provided “by far the strongest single class of facts in favour of’ his theory of common descent - (On the Origin of Species). Darwin noticed similarities in vertebrate embryos in their early stages. In this he was supported by Ernst Raeekel, a German biologist, who made drawings of these embryos, which Darwin accepted. In 1997, an international team of scientists led by embryologist Michael Richardson, compared Haeckel’s drawings to photographs of actual embryos at various stages of development."

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Charles Darwin’s 199th birth anniversary falls today

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by Dr.V.J.M. de Silva

Today February 12th the birthday of Charles Darwin is observed in several countries as Darwin’s Day.

(February 12, Colombo, Sri Lanka Guardian) In the July 2000 issue of Scientific American, Ernst Mayer, a former professor of zoology at Harvard University, announced in an article titled, “Darwin’s Influence on Modern Thought” - “No educated person any longer questions the validity of the so- called theory of evolution, which we now know to be a simple fact”. He went on to say, “Likewise, most of Darwin’s particular theses have been fully confirmed, such as common descent, the gradualism of evolution, and his explanatory theory of natural selection.”

Indeed, in 2001, the US Public Broadcasting System ran a six part TV series supporting this contention. This was challenged by some scientists who put in a two page advertisement in The Weekly Standard of October 1, 2001. “We are sceptical of the claims for the ability of random mutation and natural selection to account for the complexity of life. Careful examination of the evidence for the Darwinian Theory should be encouraged.”

The Icons of Evolution

Going back to Mayer, what are these facts that make him so sure of his grounds? The writer of this article has spent several years of his retirement studying the subject of evolution. What is set down here is based on this study. If you ask any educated person how we know that evolution is a ‘simple fact’, the chances are he/she will list out all or some of the following.

1. Miller-Urey simulation. Production of amino acids, the ‘building blocks’ of living cells, in the laboratory;
2. Evolutionary ‘tree of life’, reconstructed from the fossil and molecular evidence;
3. Similarities in early embryos of different animals;
4. Similar bone structure in different vertebrates;
5. Archaeopteryx, the missing link between reptiles and birds;
6. Darwin’s finches on the Galapagos Islands;
7. Peppered moths on tree trunks as evidence for natural selection;
8. Fruit flies with extra pair of wings as showing raw materials for genetic mutation
9. Branching pattern of horse fossils that refute the idea that evolution was directed;
10. Ape-like creatures evolving into humans.

These examples have been so frequently used that they have been called the “icons” of evolution. (Jonathan Wells, Icons of Evolution - 2000). Yet all of them, in one way or another, misrepresent the truth Let’s consider some of these.

The Origin of Life

The Miller-Urey Experiment - In the 1950s American graduate student, Stanley Miller and his Ph.D. advisor, Harold Urey, produced amino acids by sending an electric spark through a mixture of gases (methane, ammonia, hydrogen and water vapour) they thought simulated Earth’s primitive atmosphere, for which Miller was awarded the Nobel Prize. The electric current simulated the effects of lightning. The present thinking is that there was very little hydrogen in the earth’s early atmosphere and it probably consisted of carbon dioxide, nitrogen and water vapour. With these gases, you don’t get amino-acids even if the laboratory experiment is repeated.

The Evidence against Darwin’s ‘Theses’

As stated at beginning of this article, Ernst Mayer mentions three of Darwin’s theses which he says have been established. These are

• Common Descent
• Gradualism of Evolution
• Theory of Natural Selection

Common Descent

Darwin’s ‘ of Life does not fit the fossil record. Palaeontologists have discovered that new animal forms appear abruptly, not gradually, in the fossil record, without any obvious connection to the animals that came before. This sudden appearance of living forms at the very beginning of time is known as the Cambrian Explosion. It should be noted that Darwin himself has said the pattern of abrupt appearance (his own words), “may be truly urged as a valid argument” against his theory of Common Descent. The Cambrian explosion does not support a simple branching-tree pattern. Icon #2 is not proven.

Darwin thought that the study of embryological development provided “by far the strongest single class of facts in favour of’ his theory of common descent - (On the Origin of Species). Darwin noticed similarities in vertebrate embryos in their early stages. In this he was supported by Ernst Raeekel, a German biologist, who made drawings of these embryos, which Darwin accepted. In 1997, an international team of scientists led by embryologist Michael Richardson, compared Haeckel’s drawings to photographs of actual embryos at various stages of development. Haeckel had distorted his drawings at every turn. This led Richardson to say in Science journal, “it looks like its turning out to be the most famous fakes in biology”. (Science 277, 1997)

The pictures were fabricated and facts distorted. Icon # 3 is a fake

It is a well known fact that the bone structures in the vertebrate forelimbs are homologous; perform different functions but bone plan is similar. If homology is defined as similarity due to common ancestry, it cannot be used as evidence for common ancestry. There’s a difference between theory and evidence However it points towards a common archetype or design, not towards descent by modification. The explanation can go either way: design, or descent with modification. The evidence isn’t pointing one way or the other. Icon # 4 is dubious

What about the transitional forms like Archaeopteryx and the mammal-like reptiles, the Dimetrodons? Doesn’t this evidence show that Darwin’s picture of the history of life is right after all? No, say the critics. If Darwin’s theory is true, there should 100s and l000s of transitional forms. A scientific theory that only rarely matches the evidence, is ‘found wanting’. Icon # 5 is not proven

Theory of Natural Selection

In 1977, after a severe drought in the Galapagos Islands, two biologists, Peter and Rosemary Grant, noticed that 85% of the finches died off. Those who survived were birds that had larger beaks. They thought that this was natural selection and microevolution at work - (Peter Grant, Ecology and Evolution of Darwin Finches - 1986) All that happened was that the proportion of big beaks to small beaks increased during the drought. A more interesting fact is that after heavy rains in 1982-1983 the beak size returned to the normal pre-drought state. Icon # 6 is an exaggeration and is misleading.

These then are the evidences for evolution, which today means Neo-Darwinism (natural selection plus mutations and population-genetics). Evolution without Neo-Darwinism has no leg to stand on, and it is undoubtedly a theory in crisis. If biologists believe in the fundamental correctness of Darwinian evolution, they may set aside their misgivings of the particular ‘icon’ they know something about.

In a recent poll showed that only 12% in US believe that humans have evolved from other forms of life and “God had no part in it.” (George Gallup Organization, November 10, 2005).

Arthur Koestler said some time ago - “In the meantime, the educated public continues to believe that Darwin has provided all the relevant answers by the magic formula of random mutation plus natural selection - quite unaware of the fact that random mutations turned out to be irrelevant, and natural selection a tautology.”

If the icons mentioned above are the best evidence for the theory of Darwin, then it raises a question - is it science or myth?