The latest edition of New Scientist (my butler reads it) contains a very interesting, albeit irritating article entitled Why Darwin was wrong about the tree of life, which asserts that, what with horizontal gene transfer and hybridisation and all that malarkey, life's genealogy should not be represented, as Darwin said, by a tree, but rather by a convoluted web.
I say bollocks to that.
Yes, the history of life on Earth is indeed far more complex than even Darwin could have imagined. Life really isn't that simple. It never is. Newton's Laws of Motion are a wonderfully elegant set of equations that explain the motions of the heavens. They also, to Einstein's great regret, happen to be flawed. But they were still good enough to get us to the sodding moon. Rutherford's model of the atom is, we now realise, wrong, but it's a hell of a lot easier to explain to young would-be scientists than fuzzy blobs which don't seem to be able to make up their minds whether to be waves or particles. Such horrors are best held in reserve for unleashing on unsuspecting undergraduates. (I write from bitter personal experience.)
Darwin's tree of life is still a pretty good approximation of the genealogy of species—whatever that word means in this hopelessly complex genetic age. It's a useful metaphor that even young children can understand. It makes a great T-shirt and a damn fine fridge magnet.
Hands off our tree! Let's not throw the baby out with the bathwater.