THE BALANCE OF NATURE

Talk of ‘nature's balance, or ‘nature's way’, idealizes the way things are apart from human ‘interference’. This serves a sound rhetorical purpose when seeking to restrain exploiters. Overuse of herbicides and insecticides, and especially of substances that do not decay – at least for many ages – into harmless forms, may devastate the land. Overuse of fertilizers, and the casual disposal of chemically contaminated slurry, may ruin waterways and the aquifer. Dumping poisonous waste where poorer people live, or the other – non-human – nations of the living earth, combines stupidity and callousness. Such acts may be as genocidal in effect, or even in intention, as Hitler's or Pol Pot's – and should be judged as harshly. The lands between the Tigris and Euphrates were once fertile. Easter Island was once a wooded isle. Adding the giant Nile perch to Lake Victoria ‘to increase fishery yields’ has reduced the cichlid population by a factor of ten thousand – and much of the lake, bereft of algae eaters, is now anoxic. Cutting down the rainforest to clear land for crops may win a crop or two – but most of the nutrients were in the trees themselves, and the thin soil left exposed soon bakes hard.

Doing things differently, in other words, may have very bad results: existing creatures, exposed to a new challenge, may be forced into decline (and all the predators and parasites who fed on them will also suffer).