Monday, 27 October 2008

"Creation or Evolution" - chapter 5 - "Speciation, fossils and the question of information"

Continuing from here; series began here.

Chapter five is the third and final seeking to explain "What do we mean by evolution?". After that there is a chapter seeking to answer some objections; at 37 pages, it is also the longest chapter in the book.


If you've been following this extended review, you'll know by now that Dr. Alexander is quite good at side-stepping difficult questions for the Darwinian position by the use of a carefully crafted word fallacy. His section on "speciation", extending for several pages, is another classic example.

The key question as regards Darwinism versus creationism when it comes to speciation is this: do evolutionary mechanisms have limited or unlimited potential? To sharpen it still more, are the processes which are active and observable in the natural world today able to generate the entire "tree of life" from a single common ancestor, or not? The creationist model is that God created several distinct kinds (Hebrew, "baramin"), in which the life-forms had the potential to diversify within certain limits. The Biblical text does not give us much specific information about the limits of these "kinds"; but there are some - for example, trees and birds belong to different kinds (Genesis 1:11-12, 20-21). There is variation, but within limits, and what we end up with is not a single genetic tree of life, but an orchard - several trees in which the descendents express the potential that was latent in the original ancestor individuals.

DA, though, decides to answer a conveniently different question, and gives an irrelevant answer which does not touch upon the actual creationist case, whilst, as before, giving the impression that presumably he must be talking about something relevant and probably refuting it. To what extent he's conscious that he sidesteps the issues or not, I don't know - he never refers to any creationist publication; beliefs contrary to Darwinism are always couched in terms of "many people think" or "some Christians believe". In fact Henry Morris gets a special guest mention in a later chapter, but that sudden freak appearance will be as good as it gets.

The question DA answers is this one: is speciation possible beyond the limits set by today's definition of a biological species? i.e., is it possible for new species to form under the specific definition of "species" in contemporary science? DA introduces this question in terms of the commonly used distinction between "microevolution" and "macroevolution", defining them in terms of variation within a species, or changes above the species level, then going on to define just what "species" means - it is defined in terms of reproductive compatibility. A species is a population where the individuals can interbreed with each other but not other organisms. This is clearly a related question to the real issue, but only a smaller part of it. If "macroevolution" as DA has defined is not possible, then this would imply the creationist position is right; but whilst being a sufficient condition, it is not a necessary one. In fact, no mainline creationist believes that the limits of the Genesis "kinds" coincide or are even close to being as restricted as the definition of "species" which DA gives. . Hence again we simply have the ritual disembowelling of another straw man, whilst hood-winking the uninformed reader into thinking that he's reading a refutation of something at least similar to creationism.

Having thus set up this uncontroversial non-question, over the next pages DA explains various ways in which speciation can occur in the animal and plant kingdoms, da de dum yawn, and concludes that the macro/micro-evolution distinction isn't as useful as it seems at first glance. Along similar lines, he also discusses other interesting ways in which modern biological findings are raising questions over our idea of what a "species" is. As with other parts of the book, that would all be OK and useful, were there somewhere else in the tome where he actually addresses the real question - but he doesn't.

One point of interest was to see a Bible verse actually thrown into the chapter. What we've seen before is that in practice DA believes that the world of the Bible and the world of science have no real overlap as far as the evolutionary history of the planet goes. In particular, the Bible does not set any real limits on what conclusions science is allowed to give - contrary to an authentic Christian worldview in which the Bible is the foundation and ultimate arbiter for all true knowledge. DA's verse in this chapter, though, doesn't contradict this position - it's thrown in as an aside. We're told this:

No one actually knows the exact number of species on earth. the number already classified is around 2 million. ... Adam was brought by God in Genesis 2:19-20 to name all the animals, but we have a long way to go in finally fulfilling that command!

DA has not very closely read Genesis 2:20, because it actually states that Adam did in fact do the task which God charged him with; "And Adam gave names to all livestock, and to the birds of the air, and to every beast of the field; but for Adam there was not found an helper suitable for him." DA's interpretation seems to be that this command was part of the "creation mandate" to govern man for all time - part of the ongoing task to explore and harness the wonders of God's creation. Note, though, that DA assumes that Genesis 2:19-20 actually means species, as defined in modern biology, in terms of reproductive isolation - hence the task is to catalogue millions of species, not just to give generic names to a much smaller number of larger groupings. This muddle is truly ironic given the stern warnings in previous chapters that we must not read Genesis in terms of modern biology.

In reading through the examples that DA gives, it's noticeable that in the examples of processes involved in the production of new species, there are no examples of changes which are genuinely productive. They are all neutral or degenerative. That is, it is in terms of some change which prevented reproduction where it had previously been possible, and led to the isolation of a particular subset of creatures. This is obviously inconsistent with the key Darwinian assertion of upward progress. This is related to the key question of information, which DA addresses later in the chapter.

To be continued...

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