Amphibians are, after all, among the planet’s great survivors. The ancestors of today’s frogs crawled out of the water some 400 million years ago, and by 250 million years ago the earliest representatives of what would become the modern amphibian orders—one includes frogs and toads, the second newts and salamanders, and the third weird limbless creatures called caecilians—had evolved. This means that amphibians have been around not just longer than mammals, say, or birds; they have been around since before there were dinosaurs.
