This Father's Day is a perfect opportunity to appreciate the dads in our lives, and animals are no exception.
Here are five animal fathers who, unlike most species, take over the rearing of the brood, both before and after birth.
1. Male alligator pipefish, long slender fish with tube-like snouts, carry their young in a protective pouch before giving birth. Here's some footage of the tiny young emerging -- and already starting to feed.