Strange, wonderful things happen on them. And islands have it. But isolation endangers, too. Large populations, widely spread, absorb the damage. Ultimately, they bounce back.
Sheer abundance gives species a better chance of long-term survival.
Well, if something goes wrong, it's big trouble. An island offers little margin for error. As the author and many scientists to whom he turns make clear, islands are the small stage on which can be seen portents of a larger tragedy. Islands represent what humankind is making out of the world, as great continental masses ecologically come to resemble South Pacific atolls, and so threaten extinction to species uncountable. They started out by growing sugar cane.