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Olivia: Claws, scales, horns, and teeth, lots of animals are equipped to look, and act, downright terrifying. But a lot of the time, these appearances are deceiving. And they’re deceiving on purpose! Defense mechanisms exist, after all, to help animals evade predators when they really don’t have much else going for them.

If you’re the kind of creature that just wants to be left alone so you can eat bugs or plankton or whatever, then your best bet might be simply to look like someone that no predator would ever mess with. So, make yourself look big. Or spiky. Or, if there are some truly dangerous characters in your neighborhood, just look and act like them, and hope for the best.

There are all kinds of fascinating adaptations that animals have developed to help them find food, or to protect them from becoming someone else’s food. Here are just 8 creatures that have perfected the art of looking and acting creepy, to cover up for the fact that they’re basically harmless.

The aye-aye is the world’s largest nocturnal primate, found in the rainforests of Madagascar. It has oversized ears and haunting large yellow eyes, but its creepiest feature, by far, is its long, bony middle finger, which could put any haunted skeleton, or embittered punk rocker, to shame.

In part because of its creepy appearance, some folklore has described the aye-aye as a “Harbinger of Evil.” There are stories that warn of aye-ayes attacking people in the night by piercing their victims through the heart with their middle fingers. Which... what a way to go.

But the fact is, these bug-eyed primates have no interest in you, or your heart, or in punk rock. Instead, aye-ayes spend their time climbing on tree trunks, tapping the wood like a drummer to startle insects that live inside. Then it uses its long middle finger to dig into the trunk and scoop out its prey. So don’t be offended if an aye-aye points his middle finger at you -- he’s just out hunting for a late night snack of nutritious bugs.

We all know how terrifying wasps and hornets can be. But before you run away from this next creature, look closely. It’s not a wasp; it’s a hoverfly. Also known as flower flies, hoverflies are harmless insects that can be found in flower beds the world over. These flies are an especially prevalent example of what’s known as Batesian mimicry.

That’s the type of mimicry that’s used by a harmless species to imitate the appearance of a harmful species. In this case, hoverflies sport the same black-and-yellow bands that wasps and hornets do, but they can’t sting! Some hoverfly species even mimic the stinging behavior of wasps. If one is caught, it’ll push the tip of its abdomen into the flesh of a predator … even though it doesn’t have a stinger.

And not only are they not harmful, hoverflies are actually beneficial to gardens. They’re active pollinators, and they prefer to prey on aphids, a notorious garden pest. So think twice before you bat away a black and yellow insect... it may just be a hoverfly!

Octopuses are well known for their skills at camouflage. But the mimic octopus take the art of deception a step further. It can use Batesian mimicry to make itself look like not just one, but several different species -- most of them poisonous predators.

Normally a light brown and beige color, the mimic octopus can change its pattern to show black and white bands, and swim with its arms waving behind to mimic the poisonous spines of a lionfish. Or it can hide six of its arms and stretch into a long thin shape, to help it resemble a venomous banded sea snake. It’s also been reported to mimic jellyfish, flatfish, giant crabs, and sea anemones. But again... harmless! Mimic octopuses are bottom-feeders that live in tropical rivers, and they’d rather feast on sea worms or small crabs than you or anything like you.

Sharks, of course, have a bad reputation, thanks in large part to basic cable. And oftentimes, bigger is interpreted as scarier. Enter the basking shark, which lives in temperate oceans all over the world and can reach up to 12 meters in length. After the whale shark, it’s the planet’s second largest living fish species. And with its giant size also comes a giant mouth, filled with rows and rows of teeth. But despite this threatening appearance, basking sharks are are only interested in eating tiny zooplankton, their primary source of food.

They’re slow and passive filter feeders, using their cavernous gills and tiny hook-like teeth to catch plankton, small crustaceans, and fish as they move gently through the water. And unlike many shark species, basking sharks are thought to be downright social. Pairs have been observed swimming around each other in a kind of courtship dance, and while other sharks tend to be loners, baskers have been found in small schools, and even in groups as large as a hundred! A little spooky to see, but as long as you’re not a plankton, you have nothing to worry about!

Now, rays are closely related to sharks -- both are types of cartilaginous fish, whose skeletons are made of cartilage instead of bone. And the largest species of ray is the manta ray, with an average span of 6.7 meters between the tips of its graceful pectoral fins. Its intimidating size and its similarities to stingrays have given the manta a fearful reputation.

But despite its close evolutionary relationship to sharks and stingrays, the manta ray is not a predatory species but a benign filter-feeder. It has a whip-like tail similar to stingrays, but it lacks the stingray’s venomous barb. Apparently, the manta’s enormous size is enough to scare away most potential predators.

OK, so maybe sharks and rays and creepy primates aren’t you’re phobia. Maybe you’re more of an arachnophobe. In that case, what would you do if you saw a spider about the size of a puppy?

The Goliath birdeater is a tarantula species that’s considered the largest spider in the world, with each of legs stretching up to 30 centimeters! Its size keeps most predators away, as well as three other pretty snazzy mechanisms: For one thing, it can rub its legs against its abdomen to shed tiny barbed hairs, which can wind up in a predator’s face and eyes.

Rubbing its hairs together also makes a hissing sound, which is enough to scare most people, or non-people animals. And finally, there are those 5 centimeter long fangs, which exert a strong bite and can release venom to kill its prey. The birdeater gets its name from the fact that scientists have witnessed one specimen of this spider, in South America, eating a hummingbird! So, not exactly harmless!

But the birdeater mostly sticks to a diet of insects, earthworms, and frogs that are easily found on the ground. And its bite isn’t harmful to humans. In fact, reported human bites have been found to be defensive “dry bites” -- meaning no venom was released. Now, the hairy barbs can cause irritation and itching, so... you might not want to cuddle up with one.

And here’s one more for you arachnophobes -- or arachnophiles! The whip scorpion -- found in hot, dry habitats -- has a long whip-like tail that makes it look like a scorpion, but it’s actually a totally different kind of arachnid. The whip scorpion’s tail lacks the dangerous venom that makes a sting from a true scorpion so dangerous.

But it does have this going for it: When provoked, it can spray acid from a gland near its tail. This acid smells like vinegar, so the whip scorpion is sometimes known as the “vinegaroon.” Its bite can hurt, but its smelly acid doesn’t do any harm to humans.

Finally, there’s the reptile with the awesome name of the thorny dragon lizard. It lives in the deserts of Australia where it patiently waits in the sand for ants or other small insects to wander by. But its foraging behavior makes it easily spotted by hawks, coyotes, and other predators. So these lizards evolved several defense mechanisms, like spiny skin and bony horns protruding from their heads.

AND they can even inflate themselves to appear larger and spikier, when a threat comes around. But perhaps most terrifying about this reptile? It can squirt blood out of its eyes when provoked. This is usually the last line of defense when the lizard is about to be eaten -- the blood apparently tastes terrible to predators, so they hopefully won’t get more than one bite before deciding to find another meal.

But despite its prickly appearance, thorny dragon lizards are quite docile when handled by humans. And these guys wouldn’t hurt a fly. Although they would definitely hurt, and eat, an ant. Usually, thousands and thousands of ants in a day.

So, just because something looks scary doesn’t mean that it is. For many harmless animals, looking big and prickly and fierce is just the cheapest, easiest ways to ward off predators. And, if anything, it could be that these evolutionary tricks work a little too well, at least on us. Many of these species -- from the aye-aye to the basking shark -- have been hunted intensively by humans, because they’ve been so feared and reviled. Today, several are considered vulnerable or endangered species. But, as we’ve come to learn more about the animals’ true behaviors, conservation efforts have helped many of them rebound, and their reputations are getting rehabbed too.

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