01.22.03
Chymical progress
Matt Webb rightly bemoans sloppy scientific journalism; on this occasion a report in New Scientist that Chemistry guides evolution.
“It’s part of a quiet paradigm revolution going on in biology, in which the radical randomness of Darwinism is being replaced by a much more scientific law-regulated emergence of life,” the report quotes Harold Morowitz, an expert on the thermodynamics of living systems at George Mason University in Fairfax, Virginia, as saying.
In fact, the proponents of the theory, if we can believe the article, are saying something rather different:
“According to Williams and da Silva, eukaryotes also had to evolve a way to communicate between their various organelles. The surrounding raw materials dictated how this could be done. Calcium ions would have routinely leaked into cells, precipitating DNA by binding to it. So cells responded by pumping the ions out again.”
Forget what eukaryotes and organelles are (or, as in my case, don’t bother finding out); look at the logic.
What’s happening here is that a contingent event is being taken as a necessary one (here are some definitions made with reference to possible worlds). At this point I sense the ghosts of my intolerant philosophy professors hovering in search of a good fight, so:
“eukaryotes also had to evolve a way to communicate between their various organelles” - No they didn’t. They did this, but to declare that they had to is to derive, in philosopher’s playground taunts, an ought from an is. Strictly, we have no idea what they might have done in other possible worlds. (And, strictly, this might be laxness on the part of the journalist rather than the theory).
“The surrounding raw materials dictated how this could be done” - If the composition of the surrounding materials, the environment, isn’t contingent, I don’t know what is. It is unarguable that environmental conditions that existed in the past did exist, and that they did result in the world as it is, but this, frankly, is useless information when deciding what had to happen.
You might as well say that giraffes had to evolve because there are tall trees with high branches. They did, but only in the trivial sense that everything that has happened in our world ‘had to’ happen for the world to be as it is. William the Conqueror ‘had to’ win the Battle of Hastings. Will Young ‘had to’ win Pop Idol. Liverpool ‘had to’ beat Sheffield United last night. There is only one possible path to our world as it is, but to declare that there are no other possible situations is a spectacular failure of the imagination.
The only logical necessity in this whole picture is, in fact, the differential survival rates of mutations over time - that is, better adapted organisms must prevail over time. In other words, Darwinian evolution.
Although I’m pretty certain what will happen when Robert Williams next meets Richard Dawkins at Oxford - and it won’t be pretty.
Steve said,
January 23, 2003 at 3:12 pm
Woo - I was just thinking about this sort of stuff yesterday after reading a ‘creationism-vs-evolution’ debate on independant.co.uk. Just got me thinking to how little I know about some of the nitty-gritty of evolution, like how eyes evolved. (My main geeky science interest is Cosmology - can’t resist an issue of New Scientist with a black hole on the cover).
I guess it’s getting more and more true that science is becoming *like* a religion - that we accept some things through faith.
Jon said,
January 24, 2003 at 11:42 am
Every belief, in the end, is a matter of faith. The question, to me, is what that faith is based on.
I have faith that spring will (eventually) come; this is based on a combination of my practical observation (spring has come every year so far) and people who I regard as experts (scientists who have observed and explained what spring is and why it comes every year). If some scientists start saying there will be no spring this year because we’re heading into an ice age, I’ve got to decide which parcel of evidence I put my faith in.
On evolution, like many people, I had my mind officially blown by Richard Dawkins’ ‘The Selfish Gene’. It’s like one of those optical illusions where suddenly a very hard thing to see becomes blindingly obvious (indeed, ‘necessary’). Though Steven Jay Gould is a more entertaining, less abrasive, writer, I’d still recommend Dawkins as the most important single read on the subject (Darwin aside).