The process of oxygenating a body differs among many animal species. Mammals have lungs that expand and contract for proper ...

When you and I take a deep breath, we pull air into our lungs. That’s because humans are mammals. But fish aren’t mammals. They usually don’t breathe air. They usually don’t have lungs. That’s what I ...

Most people assume that fish are perfectly safe underwater and that drowning is impossible for them. After all, they are uniquely designed for life beneath the surface. But the idea that fish cannot ...