Enter the weird world of the echidna—a mammal in a category all its own
Native to New Guinea and Australia, these animals are the size of a house cat but a whole lot stranger: tiny toothless mouths, quill-like hairs...and multiheaded genitalia.
A baby echidna is a puggle. A group of echidnas is a parade—unless they’re mature males waddling after a female in mating season, in which case it’s a train (often with a younger male at the end, like a callow caboose). These love trains may grow to 10 or more males and may trail a female for days, until she signals the last stop by stretching out on the ground. Then males dig a rut in the earth around her and, sumo-wrestler style, try to shove each other out of the ring. The victor gets to mate with her first—and his male member looks purpose-built for that task.
The penile shaft has four heads, each plumbed to