When animals nod off, they're most vulnerable to sneaky predators. But despite the risks, the need for sleep is so strong ...

Birds are the most diverse land vertebrate on the planet, and now scientists have constructed a complete evolutionary tree of the 11,000 or so known species. This data came from hundreds of studies ...

The presents are unwrapped, the cookies are crumbs, and that real Christmas tree will become a fire hazard soon enough. Most ...

Although the phrase "what came first, the chicken or the egg" at first appears paradoxical, science confirms that the egg maintains temporal supremacy. However, a new study from the University of ...

While everyone agrees on the ethical imperative to reduce animal use, the challenge of widespread readiness will depend on partnership, proof, and continued development activities. Public perception ...

Kali Holder, a veterinary pathologist at the National Zoo, is motivated by problem-solving and a passionate curiosity about nature. Image: courtesy of Kali Holder When an animal becomes endangered, it ...