What are the things we think of as essential in our lives? The answers could be: our children, a daily walk in the park, a good stiff drink, the reading of books, a job, a vacation, a baseball team, a cigarette, or love. And yet life has a way of making us rethink. Our children move away from home, we move away from our favourite park, the doctor forbids us to drink or smoke, we lose our eyesight, we get fired, there's no time or money to take a vacation, our baseball team sucks, our heart is broken. At such times our picture of the world hangs crookedly on the wall. Then, if we can manage it, we adapt. And what this shows us is that essence is something deeper than any of that, it's the thing that gets us through. The 12 separate varieties of finches that Charles Darwin found on the Galápagos Islands had all made local adaptations, but when the ornithologist John Gould examined Darwin's specimens in 1837, he could see that these were not different birds, but 12 variations of the same bird. In spite of random mutation and natural selection, their finchness, their essence, was intact.
As individuals, as communities, as nations, we are the constant adapters of ourselves, and must constantly ask ourselves the question wherein does our finchness lie: what are the things we cannot ever give up unless we wish to cease to be ourselves?
Salman Rushdie writing about adaptation in The Guardian Review, Saturday 28 February 2009.