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I'm willing to bet that you've told a lie before. Maybe you faked being sick to get out of work, or added a few centimeters to your height on your dating profile.

And - you're not alone. In fact, we're not alone in this…. as a species. There are other animals that seem to intentionally deceive.

In other words, they lie. And the seven animals on this list are pretty good little liars, because they've got good reason to be. Cuttlefish are famous for using their incredible color-changing abilities to evade predators, but these abilities can come in handy at other times, too.

Like, they can help them tell apart potential mates. Male mourning cuttlefish tend to color themselves with pulsing white stripes during courting, while females like to use more of a mottled, camouflage-like pattern. And smaller males, colloquially called “sneakers”, take advantage of that.

When cuttlefish are ready for love, they come together in groups. And these tend to have way more males than females, so the females can be pretty picky. They usually choose mates that are large enough to fend off other suitors, which puts small males at a disadvantage.

So, sneaker males let one of those big, strong males do all the hard work of courting and getting a female in the mood for mating. And then, at the last second, they sneak in and fertilize her eggs! And that requires a little fibbing.

See, the sneaker male will actually swim between the courting male and female. And when he does, he splits his coloration down the middle. He presents the female with a nice, masculine striped pattern, but shows the male a feminine blotchy one.

As far as that original male is concerned, another female has decided to swing by—so he plays nice. Meanwhile, the sneaker male slips the female his sperm. This deception seems to pay off—in one study, sneaker males succeeded in mating 80% of the time!

But cuttlefish aren't the only animals out there lying to get the ladies. Dogs also do this. Small ones, anyways.

See, dogs communicate with their pee. It's a behavior called marking. And anyone who's ever taken a dog for a walk knows that male dogs in particular have a lot to say.

The scent of urine contains all sorts of information about the pee-er—like their age, health, reproductive status, and family line. But it might not be all about smell. Scientists think where the pee is also matters.

In general, adult male dogs aim high by lifting their legs. That's probably because the higher up the mark is, the closer it is to nose height—and the easier it is to separate from the smells emanating from the ground. But the taller a dog is, the higher it can pee.

So, researchers believe the height of a mark tells other dogs the size of its maker. And this is where things get interesting, because small dogs will actually lift their leg higher, so that their pee lands higher up. Which sure makes it seem like they're using their pee to appear taller than they actually are.

And if so, the researchers think that may be because they get some kind of social boost from seeming taller. So… It's like their version of lying on a dating profile. Now split-thumb mantis shrimp are feisty little crustaceans that live in burrows that they make.

And these burrows are a safe place to hang out, consume their meals, and woo a lover. Then, after mating, the burrow can keep the eggs safe while they develop. So, the real estate market for mantis shrimp is pretty competitive.

Literally. One that has a home is often forced to defend it from neighbors trying to aggressively evict them and take over. And if they have to, they'll lie to keep their property.

See, in battle, the biggest male with the biggest claw usually wins. That's because, in some species, mantis shrimp punches can reach speeds of 23 meters per second. And when something is moving super fast, even small increases in size can mean a lot more force.

I mean, they don't call them “split-thumb” mantis shrimp for nothing. And in fact, these claws can deal so much damage that males rarely actually fight. They just sort of wave at one another, and everyone agrees that the bigger claw wins.

Except, there's a catch: sometimes, big shrimps are just big softies. Like other crustaceans, mantis shrimp have a hard exoskeleton. And once it hardens, it doesn't expand.

So, in order to become one of those big males, a mantis shrimp has to molt. And when they molt, they're vulnerable. Not only are they soft and squishy, when they don't have a hardened shell, their big fighting, smashing arms don't work.

But you'd never know that, because if challenged, a freshly-molted mantis shrimp will bluff. They'll extend and expand their pinchers to make it look like they're ready for a fight, even though they can't really do much. This strategy works best against smaller opponents, since they're less inclined to call the bluff.

But still, it's often enough to send an intruder packing. And then, once their exoskeleton hardens, they can go back to defending their love nest with a little more honesty. Now onto Eastern gray squirrels, who are really good at thinking ahead.

When there's plenty of food around, they collect extra and store it away for when times are leaner. And they'll lie to other squirrels to protect their stash. One of the downsides of stockpiling is that other animals can come in and steal all your hard-won supplies.

So to minimize this, gray squirrels practice what's called scatter hoarding: they hide bits of their stash in different places, so if one is hit, they don't lose everything. But these mini-treasure troves are too spread out for the squirrel to defend them all, so it's pretty much guaranteed that at least some of the stockpiles will be pilfered. Now, they can try to make up for stolen supplies by stealing from other squirrels.

But they also have a way to reduce losses overall:. They lie about where their caches are. A gray squirrel will sometimes dig and then cover up multiple holes.

But they only put food in some of them. It turns out squirrels are incredibly visual, so when it comes to discovering food caches, they rely on their eyes. In other words, if they see another squirrel digging or find disturbed dirt, they'll assume there's food there, and waste precious energy excavating an area where a trickster just pretended to bury some nuts.

Research suggests squirrels dig these fake holes more often when another squirrel is close enough to watch, and will dig more of them after one of their caches gets plundered. And it seems like the tactic works! The real caches are less likely to be discovered when a squirrel uses deceptive caches, because the fakes confuse thieves.

Though, those thieves aren't always other squirrels. In at least one experiment, the plunderers were actually human college students. And yes, they also got outsmarted by the fluffy-tailed rodents.

Now, tons of animals cosplay as deadlier creatures to keep would-be predators at bay—a strategy known as batesian mimicry. But the milkweed tiger moth doesn't dress up to mimic other species. Instead, it's mastered the art of impressions.

These moths are really delicious to bats, because even though they eat poisonous plants, they don't hang onto enough toxins to make them yucky. So when they hear a bat zeroing in on them, they lie about their taste. They have a sound-producing structure called a tymbal, which works basically like a dog clicker.

A hardened scale makes ultrasonic clicks when it gets bent and unbent. And they use this clicker to imitate the sounds of less-yummy moths. They can make a pattern of clicks that sounds really similar to the warning clicks made by dogbane tiger moths and polka-dot wasp moths—both of which are toxic.

And they also happen to taste really gross. So when they're around, bats learn to stay away from them. Which is why, by mimicking their sounds, the milkweed tiger moth can trick bats into thinking it's also poisonous and gross.

Researchers have found that even when the moths do get captured, if the bat has learned to avoid those poisonous species, it'll let them go. But only if the moth's clicking tymbals are intact. That's actually how the researchers confirmed that the moths were lying out loud!

Brown thornbills are cute little birds native to eastern Australia and Tasmania. They're just the right size… for lots of predators to snack on, that is. And they're especially vulnerable when they're young and unable to fly from danger.

So these clever birds have come up with an ingenious way to keep their babies safe: they lie about who they are and what they see! Now, lots of birds can mimic other species, and in that way, lie about who they are. But they usually use those other birds' calls genuinely.

Maybe they make the screech of a hawk when they see a hawk, alerting others to its presence. Or they might make another birds' specific warning call for “SNAKE” when there is, in fact, a snake—perhaps to get more birds, regardless of species, to chase it away. But brown thornbills often pretend to be harmless birds like honeyeaters that have spotted a hawk flying overhead— even though there's no hawk.

And that's because they're trying to scare off a totally different predator, like a pied currawong, which attacks the thornbill's nestlings. Now, what's especially surprising here is that they mimic harmless species rather than something directly dangerous—like a hawk. That may be because they can't make a convincing hawk call.

But it means they're counting on the predator understanding another species' alarm call. Which turns out to be a safe bet. While currawong are hunters, they've got plenty to fear from a hungry hawk, so they stop to scan the skies or just scram when they hear the faked honeyeater call.

And that gives the wee thornbills enough time to jump out of their nest and hide in the dense leaves that surround them. Humans and our closest primate relatives are probably the most accomplished liars on the planet. We'll lie to secure mates, or food, or, well, anything we want, really.

And scientists think that our big brains and cooperative nature may be to blame. Monkeys and apes have brains about twice as large as you'd expect for their body size. And that's mostly thanks to super big neocortices, the part of the brain that handles perception, planning, moving, and language, among other things.

It's super important for interacting with one another and learning in social contexts. But here's the thing: the bigger a primate's neocortex is, the more often they lie. So scientists think those big neocortices might be the reason we started lying in the first place.

The idea is, some evolutionary pressure led our primate ancestors to start living in groups. And as part of that, they also evolved bigger neocortices, which helped them get inside each other's heads a bit so they could cooperate to reach common goals. But when you have cooperation, it's often in an individual's best interest to be a bit selfish from time to time— assuming they can keep others from finding out and retaliating.

And it's likely that the same cognitive tools which allowed our primate ancestors to understand each other and work together also helped them figure out how to cover their tracks when they cheated. So lying may actually be an inevitable consequence of cooperating. But, as great of an excuse as that may sound like, it's probably not going to go over well if your boss catches you posting.

Insta photos from the beach when you've called in sick. And while you could whip out something about how lying is only natural, because dogs and moths and thornbills lie, too, you're still probably going to get in trouble. So in most cases, honesty probably is the best policy.

Thank you for watching this episode of SciShow! And thanks especially to our President of Space, Faisal Saud. We're not lying when we say we wouldn't be able to make SciShow without the support of patrons like Faisal.

So thank you. If you're not a patron yet, but want to learn more about becoming one —including how you can be President of Space like Faisal— you can head over to Patreon.com/SciShow. [♪ OUTRO].