She pulls on a broad green leaf still attached to a branch and points out a shiny clutch of jellylike eggs. “These guys are hatchable,” she says. Red-eyed tree frogs, Agalychnis callidryas ...

After the females of some species of glass frogs lay their sticky eggs on the undersides of leaves that dangle above flowing water, the males guard the fertilized eggs from hungry insects ...

But frogs aren't the only animals that go through metamorphosis. Butterflies also go through a lot of changes during their life cycle. The female butterfly lays her eggs on a leaf, out of which ...