The American dipper, a drab-looking bird no larger than a robin, is a splashy rarity: a songbird that swims and even walks underwater. This round-bodied gray bird with short wings and a stubby tail is ...

But blue feathers result from refraction ... each individual strives to protect enough real estate to guarantee steady fishing and a good nest site. "These tiny little birds have got to hold ...

“Even these spines from this really odd, derived group of fishes, the pufferfish, still use the same set of genes that makes hair, feathers, fish scales, and shark dermal denticles.” Pufferfish belong ...