Imagine a puddle waking up one morning and thinking, 'This is an interesting world I find myself in, an interesting hole I find myself in, fits me rather neatly, doesn't it? In fact it fits me staggeringly well, must have been made to have me in it!' — Dougles AdamsWhile we hear creationists make the same mistake as the puddle in the above quote, we should expect better from serious, respected scientists. And this is why I am particularly disappointed with the first episode of Earth: The Biography. The geologist Iain Stewart is certainly no creationist, but he does he does help feed their hunger for quotes that they can misrepresent by, well, talking like a puddle.
Stewart is selling the coolness of volcanos by telling us how important they have been and continue to be for life on Earth. Personally, I think that they are cool enough without someone having to show how they're personally relevant to me, but that is one of the many reasons I'm not a television producer. And of course he is trying to make a point about the importance of maintaining a healthy amount – not too much, not too little – of carbon dioxide in the Earth's atmosphere. But in the process he talks about the dynamic of plankton sucking CO2 out and certain volcanos pumping it back in as keeping "just the right amount" of carbon dioxide in the air for life.
But what an extremely self-centered view that is. If the global temperatures were different than they have been for the past few million years, then clearly life would still exist. But it would be different than what it is today. I'm assuming that most people reading this (are there any) don't need this point spelled out. Under different conditions life would evolve differently, but would fit just as snugly to its environment.
Why is this mistake so easy to make?
I offer a question with no answers. But I think that the question is important. Why is it so easy for smart people like Stewart to make this mistake? I think that there is something more interesting than an ordinary little fallacy here. Just as people like to attach great meaning to accounts of our origins (after all religious people attack evolution much more than they attack astronomy, although both are incompatible inerrant scripture) there is great meaning ascribed to what it took for us to be here. My simple guess is that teleological thinking about evolution is not just limited to the religious. We think of things in terms of the process that led to us. It is the story of us.
This inclination to see the development of life on Earth as the story of us can seep into the thinking of those who really do know better. In many cases this tendency is harmless, but in other cases in can be very misleading. So we should be on our guard to do things like call Iain Stewart in the BBC to task for falling pray to this.