My Favourite Misconceptions About Evolution

Thursday, 28 November 2002

There's a debate going on at the moment (or at least there was this morning) in one of John Quiggin's comment threads about Janet Albrechtsen's article in yesterday's Oz. It's gotten into the the area of the relationship between IQ and social status (always a good topic for controversy) and the relationship of 'Darwinian thought' to politics. I think it might be useful to clear up a few misconceptions about evolution, even if in the end, they turn out to be my own.

As I said in the comments thread, the theory of evolution isn't exactly rocket science, but it's not entirely simple either. Most of the difficulties arise from carelessness in the way evolution is described as a process, plus a few confusions that arise from the use of intentional language (the kind we use to speak about people and their motivations) and misinterpretation of the phrase "survival of the fittest". Once again, blogger limitations have required that I post this as a two parter.

Evolution is purposive.
We may as well get this one out of the way first up, because it's the biggest and most of the others in some way are derived from it. On this view, human beings and other organisms are the way they are because this is the way nature "intended" them to be. Wrong: this is the way we turned out to be. Evolution is a natural process: it's no more purposive than a tile falling off your roof. It's just something that happens.

Evolution is benign benevolent.
Closely related to the first misconception is the Panglossian view that evolution is, in the long run, beneficial because it creates organisms that are fitted to their environment. Wrong: evolution happens because some individuals in any population are less fitted to their environment than others and die before they reproduce. Change the environment and the balance of adaptive advantage may change, favouring those who were formerly the less fitted of the population. Or no individuals may be sufficiently adapted to the new conditions to survive and reproduce and the species becomes extinct.