An echidna is a small, spiky mammal that lives in Australia and New Guinea. Picture a creature about the size of a house cat, covered in sharp spines like a porcupine, with a long snout like an anteater and tiny eyes. Echidnas waddle along the forest floor using their strong claws to dig into ant nests and termite mounds, then slurp up insects with their long, sticky tongues.

What makes echidnas truly remarkable is that they're one of only five living species of monotremes, mammals that lay eggs instead of giving birth to live young. (The platypus is the other well-known monotreme.) A mother echidna lays a single leathery egg, which she keeps warm in a pouch on her belly. When the baby hatches, it's called a puggle, and it stays in the pouch drinking milk until its spines start growing in.