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Miskien kan Angus iets leer uit die volgende uittreksel uit ’n resensie van twee "fabel"-boeke:
Jerry A Coyne: Why Evolution is True.
Richard Dawkins: The Greatest Show on Earth. – The Evidence for Evolution
Coyne gives his interpretation of the “modern theory of evolution”: “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 (not all) of evolutionary change is natural selection.” He then explains how changes in DNA due to mutations result in new species developing, causing the evolutionary tree to branch out.
Dawkins explains, in a masterly way, the same concepts by tracing back the family tree of an arbitrary female rabbit along the matriarchal line towards her ancestors: “We walk along the line of rabbits, backwards in time, examining them carefully like an inspecting general.” He goes on to explain that very gradually one will notice that the ancient rabbits look different from modern rabbits and more and more like a shrew. Eventually one will reach the common ancestor that rabbits share with leopards. In the thought-experiment Dawkins takes a “hairpin-bend” at the common ancestor and now move forwards in time, noticing the gradual evolution through the ages towards the modern leopard.
Dawkins describes evolutionary scientists to be in a similar position as “detectives who come late to a scene of a crime”. In both books fossils are presented as one of the strongest items of evidence for evolution. Coyne states that the “story of life on Earth is written in the rocks”, albeit an incomplete record. A fossil is a cast of a living creature, compressed into rock by the sediments piling up on top. He explains that if the entire course of evolution (4600 million years) were compressed into a single year, the earliest bacteria would appear at the end of March, multicellular life the middle of November (not stated by Coyne, but inferred from data in the book) and the first human ancestors only 6 a.m. on December 31. He challenges anti-evolutionists to explain why fossils found in the deepest layers are those of the more primitive life forms while shallower layers contain more developed species - in the sequence: jawed fish, terrestrial plants, tetra pods, reptiles, mammals and birds. Expanding on the detective metaphor, Dawkins refers to the problem of establishing the “time of death” of the fossils. This information is obtained by determining the age of the layers above and below the fossils by radioactive dating. He explains the process, involving atoms and their isotopes in detail for everyone to understand. With regard to the objections of anti-evolutionists to the accuracy of the dating process, Coyne points out that the dates determined using coral growth rings correlate well with radioactive dating.
Dawkins remarks that the fossil record is not necessary as there is enough other evidence to prove evolution. On the criticism by Young-Earth anti-evolutionists regarding the “gaps” where no fossils were found, Coyne retorts that the formation of fossils requires very special conditions as found in river beds and at the bottom of the ocean; furthermore species without bones and shells do not fossilize well.
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