During his regular checkup, a 9-year-old clouded leopard named Masala undergoes a procedure to get a tiny heart monitor implanted under his skin at the Smithsonian's Conservation Biology Institute in ...

After the baby's parents agreed to the procedure, Fae underwent her transplant on Oct. 26, with PEOPLE writing that "Dr.

Imagine you could grow a new limb or a new organ. We would be able to live forever if that were the case. However, while we ...