5. Bee Lice
No bigger than the head of a pin, insects of the “Braula” genus live clinging to the fuzzy body of a honeybee and feed on nectar straight from the host’s mouth, even tickling the bee’s face until it regurgitates. Interestingly, these “lice” are actually flies, like the common housefly, but completely devoid of wings. Why bother with them, when you live on another winged insect? Think of it like a tiny kiwi living on an eagle…and drinking its puke.
4. Naked Bat Earwigs
You’ve probably never heard of the Malaysian hairless bulldog bat, one of the world’s rarest bat species. Even more unusual, this oddball mammal is home to an equally oddball bug: a tiny, louse-sized earwig living in the folds of the bat’s naked, wrinkly body- where it is thought to feed on collected skin oils or other secretions. We aren’t really sure, because we barely know much about these bizarre bats themselves.
3. Beaver Beetles
Though they look like a cross between a flea and a louse, Platypsyllus are actually just highly unusual beetles (as are fireflies, ladybugs and weevils). They are found living solely in the nests and fur of beavers, but cause no harm at all. Feeding on dirt, dead skin flakes and even other bugs, these insects are generally considered commensal or may even be beneficial.
2. Snail Flies
If you thought the bee lice were weird, Wandolleckia is another genus of flightless fly, though in this case it’s only the female that lacks wings. They spend their entire lives swimming in – and eating – the slimy coating of the giant land snail, Achatina achatina, while the winged males fly from snail to snail mating with the lovely mucus-dwelling ladies.
1. Whale Lice
Reaching up to a full inch in length, these crustaceans might be the largest body bugs on Earth, which is hardly surprising considering that they live exclusively on whales, where they feed harmlessly off algae and flaking skin. Once overlooked by biologists, we now know that their genetics closely parallel the genetics of their hosts, differing between whale lineages and even between individuals as a part of every animal’s unique identity. This is particularly true for the three species of “Right” Whale, whose characteristic white “lumps” are actually thousands of lice clinging to special patches of rough skin. These patches serve no other known purpose, but the patterns of white lice make every whale immediately recognizable to observers and perhaps even to their own kind. Hey, at least it’s prettier than your driver’s license photo.