Hair, nails, and horns, all made up of keratin, are some of the hardest and most resilient structures in animals. Inside zebrafish cells, keratin plays a distinct role, giving them the strength they ...

Reptiles have been growing armor in their skin on and off for hundreds of millions of years, but scientists never fully ...

A fully grown kangaroo can tower over people, bound across the Australian landscape in giant bounds, and pack enough muscle ...