Brushing up on Evolution
In recent years I have collected material on evolution including Darwin's The Origin of Species (from Prometheus Books) as well as books by Richard Dawkins, Matt Ridley, Richard Leakey, Paul Davies, Alan Walker and Stephen J Gould. So I have a fair knowledge of the subject. When a 12-year student wrote in to the Humanist Society of SA asking for the Humanist viewpoint on the topic 'creation/evolution science'. I wrote the following reply, which I hope, might be useful to others.
The topic 'creation/evolution' science in my view is about two different things; creation science is about a religious view of the world, which is not really scientific. Of course they will say otherwise and quote all the scientists, which they claim speak on their side (but these are usually scientists in another field of study). They also attack evolution scientists on the grounds that evolution 'is only a theory' ignoring the facts on which it is based. The topic has been and still is an argument of religion against science but I will try to put the scientific arguments for evolution and it is up to you to find out about the religious viewpoint, but don't only look at Creationist material, there are many religious people including some bishops who accept the scientific view and want to revise bible teaching or interpretation.
Firstly, consider the animal kingdom, if you compare animals what should strike you is their similarities. If you take all the skeletons of mammals from man down to the smallest mammal you can find, and line them up in order of size (as was once done in Hornimans Museum in London) and you examine any two adjacent skeletons then only an expert will be able to tell the difference. More recent research shows that all life right down to microbes is based on DNA. The more alike organisms are the more they share common sequences of DNA. For example chimpanzees and humans have 98 per cent of their DNA in common. Respectable religious people wont object to this! If God found a good life plan why shouldn't he stick to it?
Next consider the evidence of the rocks, geologists tell us that tectonic plates build up mountains which are weathered by rain and winds to form layers that got compressed to form rock. Various methods have been used to date the layers and a very solid agreement has been reached about these ages right back to the beginning of the world some 3600 million years ago. Most animals that die become unidentifiable in a few years but in rare circumstances a fossil is formed. Examination of fossils shows that the simpler forms are found at the lowest levels and this is graded up to the most advanced animals at the highest or most recent levels. This is just what you would expect from Darwin's theory but Darwin did not know this at the time, he based his theory on the changes that took place to species when they became isolated by geographic causes. (amongst many other reasons.) Some years ago a scientist who had researched a particular kind of shell addressed the Humanist Society of SA. He found that the simplest kind of shell occurred at the lowest level and at more recent levels the shells became progressively more complex and convoluted. He was certain that this was very strong supporting evidence for evolution.
Reasonable religious people accept the dating, pointing out that a day in the life of God would be like a million years to us. Those who insist on biblical truth try to compress history into 5000 years and have man coexistent with the dinosaurs. In fact the dinosaurs became extinct 65 million years ago whereas the hominids have only occupied the last 4 million years or less.
I shall close with a reference to Man. It used to be said that there was a 'missing link' between man and ape but today there are many known hominids. The following is condensed from:
- Australopithecus ramidus (4.4 Myrs) A very early hominid (or early chimp?) not well known, its teeth are both ape-like and human-like.
- Australopithecus afarensis (3.9 Myrs) some excellent fossils ('Lucy' etc) fully bipedal, definitely a hominid but a very ape-like hominid. Brain 375-500cc ape-like teeth.
- Australopithecus africanus (3.0 Myrs) A more slender lineage. Up to five feet tall with slightly larger brain up to 550 cc and smaller teeth. These hominids are almost perfect ape-human intermediates, and it is now pretty clear that the slender australopithecines led to the first Homo species.
- Homo habilis (2.5 Myrs) Straddles the boundary between australopithecines and humans. Was about five feet tall, face still primitive, smaller molars. Brain 500-800 cc. First user of clumsy stone tools.
- Homo erectus (1.8 Myrs) includes 'Java Man', 'Peking Man', 'Heidelberg Man' looking more human. Brain 775-1225 cc but still with thick brow ridges and no chin, spread out of Africa to Europe and Asia. Made good tools, first user of fire.
- Archaic Homo sapiens (500,000 yrs ago) first primitive humans perfectly intermediate between H erectus and modern humans, brain 1200cc and over the next 300,000 years teeth got smaller, skeleton less muscular.
- The Neanderthals developed in Europe 125,000 years ago, same species, different subspecies with a larger brain 1450 cc. Known to have buried their dead.
- H sapiens sapiens (inc 'Cro-Magnons', 40,000 years ago) All modern humans. Average brain size 1350 cc. In Europe, gradually supplanted the Neanderthals.
I don't know what religious people think about the evidence of these skeletons; they do seem to justify the Darwin theory. One would have to ask them, was their God using the method of 'survival of the fittest' in His creation, or (particularly in the sad case of the Neanderthals) - just experimenting ?
I also sent a copy of an article 'Evolution is a Fact and a Theory' which can be found on the web at http://www.talkorigins.org/faqs/evolution-fact.html.
The student sent a thank-you letter - it was just what was wanted.
In conclusion, a recent Robyn Williams programme, "Ockham's Razor" on June 18 celebrated the life of William Hamilton, the New Zealand scientist who in 1964 pointed out that individuals do not consistently do things for the good of themselves, they consistently do things that benefit their genes - not their personal genes but the genes of their group and it is this which makes altruism possible and allows animals to co-operate. Evolution is not just a system of kill or be killed.
*Dick Clifford is President of the HSSA, editor of the SA Humanist Post and former CAHS Secretary.
