Researchers have long believed that all four-limbed animals or tetrapods, a group that includes amphibians, reptiles, and mammals,  evolved from an ancient group of fish known a...

Andean Condors, which weigh between 20  to 30 pounds (9 to 13 kilograms) and boast a wingspan of more than 10 feet, are one of the world's heaviest and largest flying birds.  Ye...

The San Francisco Zoo's annual "March of the Penguins," to celebrate the graduation of their Magellanic penguin chicks from "fish school," is usually attended by hundreds of che...

Given their reputation as solitary creatures that come together only to mate and hibernate, the notion of snakes hanging out in groups with their "best friends" may sound a litt...

Bei Bei's 2019 departure from the  Smithsonian's National Zoo, to join the giant panda breeding program in China's Wolong Nature Reserve, left a big void for fans. What made the...