Ninety years ago, scientists were debating the question of animal dispersal. How come there are kangaroos in Australia, and none in southern Africa --which seems, environmentally, very ...

A frog with a sticky—and sharp—tongue, and a friendly fly are a dynamic comedic team in six brief, silly episodes perfect for beginning readers. Tricky Frog usually gets the upper hand, ending up with ...

There are places where frogs could be — but aren't. Ninety years ago, scientists were debating the question of animal dispersal. How come there are kangaroos in Australia, and none in southern Africa ...

There are places where frogs could be — but aren't. And places where frogs could be — and are. Scientists in the 1930s hadn't yet come up with the notion of plate tectonics (that continents break up ...

There are places where frogs could be — but aren’t. And places where frogs could be — and are. Ninety years ago, scientists were debating the question of animal dispersal. How come there are kangaroos ...

Ninety years ago, scientists were debating the question of animal dispersal. How come there are kangaroos in Australia, and none in southern Africa --which seems, environmentally, very ...

Two Harvard professors. One on a rooftop with a bucket of frogs. The other in the front yard, down below. Ready? Get set. Throw! There are places where frogs could be — but aren't. And places where ...