Bad Evolution 2 - 'Bird Funerals'

A while ago I threatened to start a series on 'Bad Evolution' - not because I disagree with the principle that things could 'evolve', but because the way that evolutionary matters are presented in the public domain often shows an ignorance of basic Darwinianism, even whilst it seeks to promote it.

Thus the BBC (who are often the perpetrators) served up a good one today in a story on 'bird funerals'. Apparently, when Western scrub jays discover the dead body of one of their kind, they fly down and gather round it.

And then comes the 'bad evolution' bit: "The behaviour may have evolved to warn other birds of nearby danger, report researchers in California, who have published the findings in the journal Animal Behaviour."

The problem is, of course, the word "to", as in "The behaviour may have evolved to warn other birds", because in the 'standard theory' there is no 'to' or 'so that'.

The 'standard theory' of evolution, as I understand it, is that a fresh characteristic - in this case a particular behaviour - conveys a significant breeding advantage in those organisms possessing that new characteristic, which means that more of them come to exist over time.

So we could say, "When this behaviour emerged amongst jays it may have resulted in a greater breeding opportunity for those bird populations in which it warned others of nearby danger and allowed them to out-breed those populations which did not possess this characteristic." Not nearly as succinct as 'to', but not as misleading either.

Of course we also have to presume that this was a population phenomenon, because the birds 'being warned' are not necessarily the same as those doing the warning, and I can see how the former might have gained a breeding advantage, but I wonder about the latter. In fact, I would have thought flocking round a dead body, if the death was the result of disease or predatory action, was likely to mitigate against more breeding opportunities, since you were more likely to become infected or get eaten. But presumably it must have worked something like what is being suggested. (Or maybe 'compassionate' birds were perceived as the sensitive kind and could more easily get mates -- who knows?)

Incidentally, I think I am right in saying that 'survival' per se can never be an evolutionary driver, since it merely means you stay the same but don't get eaten, starved, drowned, fried or whatever. It is not 'survival' that produces change, but a fresh 'advantage', which must also be a 'significant' advantage in the sense that you actually breed more so as to pass on the new characteristic.

This is why the 'gradual change' scenario has to be nuanced. It is all very well saying that the eye, for example, could evolve by numerous small steps, but each small step still has to be big enough to convey an actual breeding advantage.

The definition of 'how small' an 'evolutionary' change needs to be is not 'small enough to be different from the previous form of the eye' but 'big enough that the organism with the new form is better equipped than its parents and cousins to the extent that it breeds more'. Remember, we are talking about 'natural selection', and the natural selection must be not what survives but what excels. At least, that is what I've understood.

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'Bad Evolution' - 1

Let me make this clear. Although all Christians believe in a creator God, I am not a 'six-day' creationist. Since the days of Augustine of Hippo (4th/5th century AD), there have been those who read the text of Genesis as indicating something other than a world coming into being over six twenty-four hour periods. So I'm in relatively orthodox company. Nor am I in principle 'anti-evolution'.

BUT, given what a hotbed of debate the subject is, I can't help noticing there's some very bad things being said out there about the evolution -- what I call 'bad evolution' -- and there's a classic on today's BBC News website.

The link from the front page is titled, "Why zebras evolved their stripes". Well, that's wrong for a start. There is no 'why' about evolution, because evolution (at least as currently proposed) does not take place in order to do anything. Rather, changes happen (rather like other stuff) and there are consequences in terms of survival rates, and that's evolution.

It is rather like me discovering a better way the other day to set up my e-mail. It was entirely accidental. I had no idea I was doing anything different, but the outcome was very satisfactory. That is how I have now set up the e-mail on both my computers. I have 'evolved', but there was no 'why' about me making the initial change. It happened accidentally, and I selected it. Understood?

'Bad evolution', however, is shot-through with 'why' and 'in order to' statements. So the actual headline continues in the same vein: "Zebra stripes evolved to keep biting flies at bay".

Oh no they didn't. They may have had the effect of keeping biting flies at bay, but that was entirely fortuitous. The weasel word here is 'to'. It is like saying, "I changed my computer configuration 'to' make my e-mail more efficient." No I didn't. I changed it (accidentally) and it had that it effect. There was no purposeful 'to'.

But the report continues in the same vein (I've left out the paragraph breaks): "Why zebras evolved their characteristic black-and-white stripes has been the subject of decades of debate among scientists. Now researchers from Hungary and Sweden claim to have solved the mystery. The stripes, they say, came about to keep away blood-sucking flies."

Once again, no. Evolutionary theory dictates that the stripes just came about, but were perpetuated because the stripier a zebra, the more its chances of breeding, compared with less-stripy zebras.

Why do I make this point? Because loose talk like the above gives completely the wrong impression about evolution -- that somehow it is a 'force' driving change towards goals. It is NOT. There is no 'in order to', and giving the general public the opposite impression is bad science -- and 'bad evolution'.

(The reason for the '1' in the headline above is that I've noticed this happening so often, I intend to make this a series!)

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