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From today’s “Letters to the Editor” in today’s NZ Herald:

Your correspondent correctly states that Charles Darwin’s theory of evolution is under threat.

The main threat, however, is not coming from “conservative religious school.” It is coming from science.

Well, as a scientist, this is news to me. What scientific evidence does our correspondent present in support of this supposed ‘threat’?

In the past decade, especially, incredible advances in micro-imaging have revealed the amazing interior of our body’s cells among many other biological wonders. The stupendous complexity of these microscopic structures is leaving scientists flabbergasted.

None of the biologists I know could be described as ‘flabbergasted’ (adj: “overwhelm[ed] with shock, surprise, or wonder“) as they learn more of the cell’s fine internal structures. Not in what I suspect is our writer’s intended sense, of being so shocked & surprised that they’re ready to throw out all they know about evolution & how it functions. (I wonder if by ‘micro-imaging’ he means videos like this one, which is an animation developed by XVIVO for Harvard University.)

Just as a taster, Google “bacterial flagellum” and discover an acid-powered motor inside the cell with a shaft through the cell wall fitted with a propeller that moves the cell about.

I did – & the first entry on the search page is this one from Wikipedia, which gives a clear, factual description of the current state of knowledge of flagellum structure and function. Incidentally, the flagellum evolved at least three times, in Archaea and the ‘true’ bacteria, and in eukaryotes (the group that includes plants, animals, fungi, & single-celled organisms) – you have to wonder why our writer’s designer would tinker like that…

His description of the ‘motor’ is intriguing. The ‘acid-powered motor’ is a complex of proteins, & its movement is powered by the movement of hydrogen ions across a membrane (in the same way that production of ATP in mitochondria uses movement of H+ ions). The word ‘propeller’ may be intended to conjure up images of a boat’s propeller (with all its connotations of a designer), but the flagellum looks nothing like that.

While we’re on the flagellum, our writer seems unaware that the idea that this example of ‘intelligent design’ was comprehensively dismissed during the ‘Dover trial‘. Yes, I know he doesn’t come out and use those words or the term ‘specified complexity’ (hinted at in his next paragraph), but his intent is clear – there’s a designer. Ken Miller has written a clear overview of the whole argument about flagellal origins.

Mathematicians have determined there is no way that such complex structures could accidentally self-form, as required by Darwin’s theory, within the entire life of the universe, let alone in a paltry few millions of years.

Which mathematicians? Jason Rosenhouse has written an interesting post on the issue of improbability & evolution. He notes that those espousing our writer’s view “typically toss off combinatorial arguments in which the probability of evolving some complex molecule, like haemoglobin, is taken to be one over the number of ways of arranging the amino acids in that molecule. Sadly, that only works if all of those arrangements are equiprobable, but the continuing action of natural selection ensures that they are not.” And this is another point where the letter’s author goes wrong, because the process of natural selection is not ‘accidental‘. (He also seems unaware of the antiquity of life on Earth: bacteria have been around for up to 3.5 billion years – orders of magnitude greater than his ‘paltry few millions.’)

“Origin of Species”, written 150 years ago by Darwin, is incorrect and we must be more open-minded when teaching children how we might have got here.

Of course there were things Darwin didn’t know – in the absence of any knowledge of genetics, or of cell ultrastructure, at the time when he was writing, how could it be otherwise? But this does not detract from his magnificent insight, meticulously documented, that evolution by the process of natural selection could account for life’s wonderful diversity. That concept has been tested, and confirmed, and extended, time and time again since the Origin was first published.

There’s an important point to be made here. Just because science can’t currently explain something, does not mean scientists won’t be able to explain that phenomenon in the future. If the response to something novel was always “I can’t imagine how that might develop, therefore God”, then we would never have reached anything like our current understanding of how the living world operates. And we would be the poorer for it.