astronaut drifting in outer space

Admit it: At some point, you’ve wondered about what the world would be like if humans weren’t naturally grounded. Unlike many birds and insects, man wasn’t born with the biological ability to defy gravity, the force that literally keeps our feet on the ground.

According to Live Science, gravity completes the quartet of the universe’s four fundamental forces, together with strong nuclear forces, weak nuclear forces, and electromagnetism. Gravity is the force of attraction between two given objects. Everything in the universe that has mass — whether it’s a coral reef, a spider, or a popular parody singer – attracts every other object with mass (via Universe Today). The strength of that attraction depends on how massive the objects are and how close or distant they are from each other. When people hear about gravity, planets usually come to mind, which is why it can be difficult to picture how it works on a smaller scale. That’s probably also why this critical requirement for existence tends to get ignored.

But what if gravity stopped working one day? What if it disappeared, even for just ten seconds? Take note that based on physics, a scenario that suddenly eliminates gravity from Earth is impossible — which is extremely fortunate, because if that were to happen, these terrible, terrible things would certainly follow.

You would lose muscle mass and bone strength

therapist helps man with muscle pain

Truth be told, so many things would simultaneously go wrong if gravity suddenly went kaput. Thus, it’s best to focus on the small, easy stuff first. Namely, your own body.

Astronauts have had extensive experience when it comes to living in an environment with no gravity. Nature defines zero gravity as "a state of weightlessness," which is what happens when a spacecraft’s acceleration counterbalances (and effectively cancels out) Earth’s gravity. On paper, this sounds fun — but in practice for long periods of time, it’s dangerous and even lethal to human health. Because all human beings are born on Earth, an environment perpetually under the influence of gravity, the body’s development is greatly affected by gravity’s constant downward pull. That means it’s under constant stress, and our muscles and bones develop specifically to withstand that stress. Take away gravity for an extended period of time, and that mechanical strain goes away. As a result, the body forms fewer osteoblasts (bone-building cells), leading to a loss of bone mass and greater susceptibility to fractures.

Another nasty side effect: As the calcium normally stored in your skeleton gets released into your bloodstream, you’ll suffer renal stones, bowel movement problems, and more (via Wired). And as the What If Show explains, studies have shown that astronauts in space experience significant losses in both bone strength (14 percent after six months of being on a space station) and muscle mass (up to 20 percent in just 5-11 days).

Your sense of balance would be thrown out of whack

man standing on one leg

Fun fact: Humans have more than five senses. One of the most important ones — and one that we tend to take for granted — is our vestibular sense, which is what helps us tell up from down and prevents us from falling over. This internal sense of balance is what allows people to ride bikes, walk along a straight line, stand on one foot, or move their heads and limbs without getting disoriented.

Nature explains that all of this is made possible by the intricate system in every person’s inner ear that keeps track of the body’s movement, the different directions and how they relate to the person’s current position, and other aspects that play a role in making sure the person doesn’t become a disoriented, headache-plagued heap on the ground. And as you’ve probably guessed by now, gravity has a lot to do with it.

Admittedly, the balance-setting organs in the ear (the otoliths and semicircular canals) technically aren’t necessary for a human being to survive. However, taking them away would bring tremendous suffering. Or, as Wired succinctly puts it: "Imagine a gently oscillating, nausea-inducing scene from which there is no escape. That’s what it feels like when the organs of the inner ear malfunction."

Your red blood cell count would fall

red blood cells in human body

According to the What If Show, a human heart pumps approximately 2,000 gallons of blood on a daily basis. This organ’s critical role in keeping you alive is possible only because of gravity: As your body has gotten used to living on Earth for pretty much your entire life, the amount of effort your heart exerts takes gravitational force into consideration. Suddenly removing gravity from the equation would cut off blood from vital parts of your body, including your extremities and your digestive system.

Nature explains that sudden disappearance would also drastically affect your blood pressure. Normally, the brain bears about 60 to 80 mm Hg (millimeters of mercury) worth of pressure, while the feet, which bear your entire body weight, reaches up to 200 mm Hg. This ideal balance in our blood pressure is possible to maintain because gravity keeps it that way.

Here’s what would happen if gravity suddenly disappeared: Your blood pressure would become about 100 mg Hg across your body, and its effects would quickly manifest: Your face would swell with fluid as your legs get drained, your eyesight would be tremendously diminished, your blood vessels would rupture, and you might even suffer a stroke that could leave you with permanent brain damage. Per Wired, your red blood cell count would fall. A low red blood count, generally known as anemia, leads to possible oxygen deficiency, a longer recovery time for injuries, and a severely compromised immune system (via Medical News Today).

You wouldn’t be able to sleep well

young woman suffering from insomnia

Despite the endless hours scientists have devoted to studying it, there’s still no conclusive answer as to exactly why humans need sleep to survive. What experts do know, however, is that gravity has a strong connection to sleep patterns and the quality of sleep a person gets — and without it, both of those would be greatly impaired.

As The Conversation reports, astronauts rarely get some decent shuteye when they’re off-world. This is especially the case during long-term spaceflight, in which the astronauts are subjected to a long period of low gravity. Even the seemingly simple act of lying down becomes a Herculean feat for them because, well, how exactly do you lie down in a setting where there is no "up" or "down?" Their internal clocks, which affect their sleeping patterns, are thrown into disarray. Plus, because there’s no gravity to hold them down while they try to sleep, tightly secured sleeping bags are a must.

Additionally, even if you manage to fall asleep, it’s unlikely that you’ll get enough. A 2018 study concluded that since gravity affects the human body during a person’s waking hours, it is partly responsible for sleep. The study also affirmed that gravity conditions Rapid Eye Movement (REM) sleep, aka the part when you dream. According to Biology Online, this is only achievable when a body is lying down properly. (Interestingly, this is true not just for humans but for horses and elephants, too.)

Nothing would stay in place on Earth

random furniture floating

Perhaps the most obvious effect of the sudden disappearance of gravity is that nothing would stay in place. You might even be picturing it as everything gently drifting off into the sky, as if fairies had sprinkled pixie dust all over the planet, or something. However, the reality of what would happen is far from the scenario you’re probably imagining: It’s a lot more chaotic, somewhat comical, and unexpectedly violent.

As HowStuffWorks explains, gravity is the reason why your car, the stuff inside your office, and even your parents and siblings manage to stay on the ground. Keep in mind, however, that Earth is in constant motion. According to Karen Masters’ "Ask an Astronomer" column on the Cornell Astronomy website, a person standing at the Earth’s equator would actually be moving at a speed of more than 1,000 miles per hour. Ever notice how when a car suddenly accelerates, everything inside it that’s not properly secured gets jarred out of place, in all sorts of crazy directions? In a sense, making gravity disappear would be like suddenly removing all the seatbelts that keep things on the planet from rolling around.

Long story short, everything that’s not firmly rooted on the ground — whether it’s a person, a desk, or a car — would turn into "fast-moving tumbleweeds," as Science ABC describes. Not even houses and buildings would be safe; they, too, would end up becoming gigantic tumbleweeds of destruction.

Everything that’s not bolted down would float off into space

man with large kite floating away

Of course, once everything starts rolling around after gravity gets turned off, they won’t stay on Earth for very long. As the planet rotates, every rolling object you can imagine will start to float into space, no matter how large they are (via HowStuffWorks).

Think being inside a big building (such as your office or the mall) would save you from this fate? Think again. As this chaotic mess plays out, you’ll find yourself rolling and then floating towards the ceiling. If you somehow manage to survive this (not to mention the deluge of heavy equipment, appliances, and furniture unceremoniously flying your way), you’ll notice that the entire structure will be drifting away much faster over time. As Cornell Astronomy details, it (as well as everything else outside) would be floating away in a straight line at an accelerated pace, as it deviates from the planet’s spinning path.

Oh, and if you think that only the things that are on Earth would be affected by all of this, you’d be incredibly wrong. It’s the pull of their respective planets that keep satellites in orbit. In other words, when Earth’s gravity says bye-bye, so will the Moon (via Futurism). With nothing to keep the planet’s sole satellite spinning around it, the Moon will drift off into parts unknown.

Earth would lose all its bodies of water

beach at sunset

When it comes to discussing the effects of Earth’s gravity suddenly disappearing, the phrase "everything on Earth" literally means "everything on Earth." This includes the things that are so big that we don’t normally think of them as "things" but "places."

As HowStuffWorks explains, the oceans, lakes, and rivers on Earth stay on our planet because of gravity. Erase that from the picture, and there would be nothing to keep those all-important bodies of water firmly on Earth’s soil. It would most likely be a terrifying sight: humongous water formations rising up, making their way to space as if someone had put rocket boosters on translucent blue continents. As they drift away, they’ll likely break apart, forming smaller bodies of water that keep breaking apart as they move along (via the What If Show).

At some point, you’ll notice whales, dolphins, sharks, octopuses, and all sorts of marine life flying away, against their will, encased in their bead-like hydro-prisons. All of this may initially be fun to look at … until you notice the poor creatures dying due to shock, drastic temperature and pressure changes, and the other nasty side effects of their unexpected flights.

The atmosphere would literally leave Earth

blue sky with wispy clouds

Now, you might not consider the Earth’s atmosphere as an object that would be affected by gravity’s loss. For the purpose of this discussion, however, it absolutely counts, which is important, because this is where things go from worse to truly horrific.

Just like the Earth’s many bodies of water, gravity is the only thing that’s keeping the atmosphere, well, the atmosphere. In fact, the Moon’s comparatively weak gravitational pull is why its extremely thin atmosphere is quite different from Earth’s (via Forbes). According to the What If Show, as every object on the planet starts to tumble around, the molecules in the atmosphere would immediately begin to drift off into outer space. This, of course, includes oxygen, which not only keeps most living organisms alive.

If that doesn’t already sound horrifying enough to you, Science ABC adds that with Earth’s atmosphere disappearing, the air pressure would change quickly and significantly. If you’ve ever been on an airplane, you’ve probably experienced the ear-popping sensation that happens as your plane ascends. Now take that, but make it about a couple hundred times worse.

Earth would break apart into chunks

Earth from outer space

It’s important to stress that the chances of this nightmarish no-gravity scenario ever happening on Earth sit somewhere between zero and none. That’s because, as HowStuffWorks explains, the only way to change the planet’s gravity would be to change the planet’s mass. Since Earth’s mass is constant, and there’s nothing taking ginormous pieces away from the planet right now, there’s no danger of that happening, according to Futurism (barring any crazy cosmic-scale shenanigans straight out of science fiction, of course). That’s a relief, because if Earth’s gravity ever disappeared, the planet itself would cease to exist the way it has for billions of years.

Gravity is basically what holds this planet together. It’s the glue that keeps the Earth’s layers – the inner core, outer core, mantle, and crust — intact as it rotates on its axis and revolves around the Sun. Take that glue away, and … well, HowStuffWorks describes it best: "If Earth’s gravity became zero, nothing would hold it and chances are that its inner core would eventually burst in a lethal titanic explosion due to intense pressure. Earth would break into pieces that would float around space, wreaking havoc."

…And so would the Sun and other stars

space colorful

According to NASA, the Sun is so huge that more than a million Earths could fit in it. Due to its sheer size and massive gravitational force, this star, which sits at the center of the solar system, manages to keep Earth and other planets following specific orbits. And like our home planet, gravity is what keeps the Sun’s burning-hot gases in its ball-like form. This is also the case for other stars. As for black holes, they’re unbelievably massive, so much that even light is no match for their gravitational pull (via NASA).

If you were to expand this thought experiment and remove gravity not just from Earth but from the Sun and other celestial bodies, the results certainly wouldn’t be pretty. As the BBC puts it: "Without the force of gravity to hold [the Sun] together, the intense pressures at its core would cause it to burst open in a titanic explosion. The same thing would happen to all the other stars in the Universe." Take note, though, that due to how distant the other stars are from Earth, it’s unlikely that any Earthlings would be around to witness the celestial light show.

The universe would become just a soup of atoms

stars in space

What if this thought experiment were to escalate further? What if there were no gravity not just on Earth, not just on any other celestial body, but throughout the universe? Simply put, there would be nothing to see, distinguish, or appreciate. The entire universe would be, as Futurism describes, "completely flat and featureless."

Imagine that you could somehow step outside the universe, viewing it from outside its boundaries (perhaps through a pair of multiversal binoculars in an alternate reality). You would be looking at an empty, boring void. Because it’s gravity that makes it possible for planets, stars, and black holes to exist, there would be nothing to admire in this sad, empty version of the universe. And because there are no planets for any life-forms to live on, life as you know it would not be possible in this gravity-free expanse.

You’d die an uncomfortable death — faster than you think

clock disintegrating

To get a proper grasp of how bad things could get if there were no gravity, each of its effects have to be discussed separately. However, if this unlikely situation ever came to pass on Earth, everything awful that would happen would occur simultaneously: Your body would malfunction, various objects would start tumbling and flying into outer space, the oceans and atmosphere would float away from the planet, and the planet itself would crumble like a cookie smashed with a hammer, all at the same time. Plus, the Moon’s departure would likely cause some serious seismic activity while all of these things are happening, according to Seeker. It would be a miracle if anyone could survive these horrors for five minutes, especially since no one would be able to run, much less move. Oh, and you’d probably die sopping wet and drenched in your own sweat, because those beads of perspiration would pool all over your skin (via the What If Show).

There’s still a lot that scientists don’t completely understand about gravity, even though it’s already clear that this force is critical for life on Earth to continue. Plants seem to be especially dependent on it, New Scientist states, based on experiments conducted both on Earth and in space. It’s entertaining to ask, "What if there were no gravity on Earth?" — but it’s truly fortunate that no one will ever know the answer through firsthand experience.

Close-up of resting octopus

Scientists estimate that there are about 8.7 million different species on Earth, roughly 89% of which are animals (via Science Daily). They’ve only cataloged around a million of them, which means there are plenty more for us to discover (if they don’t end up dying due to man-made climate change, that is).

Not everything is known about all the species that have been identified, but some of the things that have been discovered are fascinating. For instance, ostriches kick hard enough to kill humans, frogs drink through their skin and not their mouths, and some jellyfish can sting even after they’re dead.

However, along with these interesting facts and impressive feats come some truly bizarre behaviors — the kind that might even make you lose sleep. From surprising self-defense secrets to repulsive reproductive rituals, here are some creepy facts about animals that will keep you up at night.

Some mammals glow under ultraviolet light

Platypus resting on a rock

The platypus is an odd creature: it looks like the hairy lovechild of a duck and a beaver, it’s a mammal that lays eggs instead of giving live birth, and it has a single orifice for both reproductive and excretory purposes (via FlipScience). It’s one of only five living species of monotremes, a peculiar animal group that, alongside a few separate Australian mammals, has a recently revealed unique trait: the ability to glow in the dark under ultraviolet (UV) light.

In a 2020 paper, researchers wrote about how platypus specimens in museums demonstrated biofluorescence (which is when an organism absorbs short-wavelength light, like UV light, and emits longer wavelengths or glows in the dark). According to CNET, this study inspired scientists at the Western Australian Museum to grab some UV lights and see if any of the 800 other mammalian species in their collection had the same ability. Long story short, their tests yielded glowing results.

In an interview with ABC News, curator Kenny Travouillon shared that a wide assortment of Australian mammals, including marsupial moles, bilbies, wombats, and echidnas, glowed under UV light. While experts still haven’t figured out the purpose of the biofluorescence, they think it’s to help the animals see each other at night.

One parasite eats and permanently replaces fish tongues

Tongue-eating louse inside fish

Can you imagine waking up one day, looking in the mirror, and seeing that your tongue had been eaten and replaced by a sinister-looking parasite? That’s exactly what the tongue-eating louse does to fishes. According to Wired, this icky isopod enters through the fish’s gills, chows down on the victim’s tongue, and then firmly plants itself there and becomes a perfectly functional replacement. This is the first and possibly only known case of a parasite becoming a working replacement of its host’s organ in the animal world, according to a 1983 paper. But it gets worse.

In at least one species of tongue-eating louse from Florida, Colt William Cook observed that the parasite is born male, turning female only after it pulls off its tongue-terminating trick. Upon successfully replacing its host’s organ, it mates with one of the other parasites that managed to enter via the fish’s gills. Their brood of all-male offspring then aggressively search for their own victims (the same species of fish), beginning the process once again when they find their target.

Scientists aren’t sure how many of these horrifying creatures are out there. Given that a single study conducted in India yielded 10 new species, this parasite’s actual species diversity could be great enough to leave scientists tongue-tied.

Ants turn into zombies via a mind-controlling fungus

Zombie fungus takes control of ant

Thanks to popular culture, zombies are thought to be mindless, shambling undead who were infected through bites and wounds and who are driven only by the urge to eat brains and flesh. In the case of zombified carpenter ants, there’s something far more sinister behind the transformation: Ophiocordyceps, a parasitic, mind-controlling fungus that, according to LiveScience, specifically targets their species.

The Atlantic details this devious parasite’s meticulous methodology. After the fungus enters the carpenter ant’s body, it takes about seven days for the parasite to sap its unfortunate host of nutrients. It makes its way up to the ant’s brain, taking control of it like a nightmarish science fiction movie made real. Entomologist David Hughes believes that this process kills the ant’s neurons while releasing the fungus’ muscle-contracting chemicals, allowing the parasite to control the hapless host like a meat puppet.

At this point, the fungus forces the ant to find a leaf that’s exactly 25 centimeters (just under 10 inches) from the ground — the elevation at which the temperature and humidity are well-suited for the parasite to thrive — and commands the insect to bite down hard. As the zombified ant remains suspended above ground, a fungal stalk grows out of its head. The stalk produces spores that will eventually fall down and infect other carpenter ants unlucky enough to crawl under it.

Horned lizards squirt blood from their eyes

Horned lizard with blood from eye

One would think that the horned lizard’s spiky exterior would be more than enough to dissuade carnivores from nibbling on it, but this North American reptile employs a host of additional defensive traits (including camouflage and self-inflation) to survive. Its most infamous ability is its blood-squirting eyes: think Cyclops of the X-Men, but with horrifying streams of hemoglobin-rich liquid instead of concussive force beams.

When the horned lizard senses danger, it contracts the muscles near the major veins surrounding its eye (via Ask Nature). This allows blood to rapidly fill the reptile’s ocular sinuses while restricting cardiac blood flow. Eventually, the pressure build-up will rupture the sinus membranes. When this happens, the lizard auto-hemorrhages, meaning its eye socket ejects the accumulated blood forcefully. Experts have observed the jet stream of blood reaching as far as 4 feet. Even more impressive is how the reptile can reportedly do this as frequently as needed within a short time frame, for reasons that scientists still can’t fully explain.

Fortunately, according to a 2001 paper, horned lizards are unlikely to blast humans with their blood. They reserve this special move for canids and felids, typically aiming for their mouths (via BBC). Apparently, this can be extremely unpleasant for the cats and dogs on the receiving end. Experts think that horned lizards’ appetite for venomous harvester ants imbues their blood with a chemical that’s particularly foul-tasting.

Sea cucumbers shoot their own organs at would-be threats

Sea cucumber shooting internal organs

If you could pick your own special biological self-defense measure, it’s a safe bet that squirting your intestines at your foes wouldn’t be very high on your list. This gross-sounding ability is similar to what certain species of sea cucumbers possess, and it’s surprisingly effective at deterring sea turtles, sea stars, crabs, and other potential predators.

Through a process called evisceration, this gutsy move involves the expulsion of some or all of the sea cucumber’s internal organs, as explained in a 2019 paper in Zoological Letters. There are two ways the echinoderm can squirt out its own guts: either through its mouth or through its back end. According to marine biologist Christopher Mah, this defensive action is made possible by the sea cucumber’s ability to soften or toughen its body texture when it wants to (just like other echinoderms). It’s a straightforward procedure: First, the ligaments and tissues that link and anchor the sea cucumber’s internal organs soften, followed by the opening through which they’ll exit. Finally, the sea cucumber’s muscles contract, shooting its guts straight out. Any threats in the echinoderm’s vicinity would start gobbling up the organ offerings, allowing the now-literally gutless creature to slip away.

The sea cucumber’s incredible regenerative abilities allow it to grow back its organs (though it takes a week to about five months to accomplish this).

Adorable aquatic animals engage in violent sex (and necrophilia)

Two sea otters in the water

If you’ve ever seen photos of sea otters holding hands as they float on the water, it’s hard not to find these marine mammals endearing. Unfortunately, sea otters can also exhibit some pretty brutal behavior. For starters, male sea otters have been known to assault and even kill seal pups. A 2010 paper talked about 19 cases, including a particularly gruesome instance where a sea otter bit a pup’s face, held it underwater, and copulated with it for over an hour until it died. Female sea otters don’t seem to fare much better under the males’ vicious reproductive strategies. An article on Vox cited veterinarian Heather Harris, who shared two reports (observed 10 months apart) of male sea otters forcefully copulating with female sea otter carcasses, and also says that one sea otter off the coast of Canada apparently assaulted and murdered a dog.

Another favorite marine mammal, the dolphin, exhibits similarly vicious and violent reproductive approaches. According to the Atlantic, sexual coercion is a part of their strategy, with gangs of male dolphins aggressively corralling a single female for the purpose of forced copulation. Oh, and this cetacean also commits infanticide: Males have been observed to kill dolphin calves, with the possible goal of adding mother dolphins, now free from the responsibility of caring for their young, to the pool of available mates (via BBC).

Deer eat meat (and even human remains)

Two deer foraging in the snow

Imagine Bambi prancing around merrily in the forest, frolicking with his animal buddies. Suddenly, they hear the adorable white-tailed deer’s stomach grumble, causing all of them to stop and giggle. Aware of his own hunger, Bambi turns to one of the little birds hopping in the grass around him… and nabs it with his jaws in one swift motion. Humor quickly turns into horror as Bambi proceeds to eat his friend, and the rest of the forest crew start running for their lives. While Disney likely wouldn’t greenlight such a movie, the scenario isn’t actually that farfetched.

National Geographic lists alfalfa, fruits, nuts, twigs, and fungi as part of the typical white-tailed deer diet. However, such a limited menu can lead to nutrient deficiencies, including lack of calcium, phosphorus, and sodium, particularly during the winter. Thus, experts have observed these hoofed mammals occasionally addressing their nutritional gaps by eating birds, fish, and even the corpses of rodents and rabbits (via the Independent).

That might not be so surprising, but deers have even been spotted chewing on human remains. In 2015, researchers witnessed a deer stumbling upon a decomposing body that had been left in the open for about half a year. The scavenging ruminant was photographed snacking on the corpse.

Oxpeckers drink the blood of their hosts

Oxpecker on buffalo's face

When it comes to mutually beneficial associations in the animal kingdom, few are as iconic as the way megafauna and oxpeckers work together. Rhinos, giraffes, oxen, hippos, and other large mammals benefit from the oxpecker’s persistent pecking. Their ticks, dead skin, and bodily secretions serve as a buffet for the tiny bird. There’s a darker side to this symbiotic relationship, though, with some evidence that in certain cases, the oxpecker actually does its host more harm than good.

According to a paper published in 2000, researchers have assumed for years that the oxpecker’s presence greatly reduces its host’s tick load. However, field tests in Zimbabwe revealed that shooing away the birds didn’t really have much of an impact on how many ticks their prospective hosts had. Worse, oxpeckers have a tendency to eat just about anything they can get from their host’s skin, including blood from open wounds. The research showed that because of their incessant blood-drinking, oxpeckers actually made the healing time of their wounded hosts considerably longer. Authors of a 2010 study noted that oxpeckers’ relationships with their hosts are "generally mutualistic," albeit with certain opportunistic "parasitic behaviors."

Still, experts know that oxpeckers have helped save at least one critically endangered species. Based on findings from a 2020 paper in Current Biology, oxpeckers’ hissing calls helped black rhinos evade would-be hunters up to 50% of the time. As black rhinos can’t see very well, the birds are a useful warning system.

This toad mama can trigger your trypophobia

Surinam toad laying down

If the idea of circular things embedded on a creature’s back makes you extremely uneasy, you may want to skip to the next entry.

Meet the Surinam toad, an amphibian that’s easily recognizable for two reasons. One, it’s flat-bodied to an almost ridiculous degree; in fact, it can easily pass for roadkill, even in the eyes of herpetologists (via Wired). This strange shape works to the toad’s advantage — it’s a suction feeder that lunges toward and sucks in passing prey, and so likes to blend in at the bottom of ponds where its camouflage skills allow it to surprise its unsuspecting meals.

The Surinam toad’s second strange trait — and the one that’s likely to give you the heebie-jeebies — is its ability to store and hatch around 60 to 100 eggs (via the San Diego Zoo) on its back. This honeycomb-like formation serves as individual wombs for the tiny froglets. Instead of spending time swimming around as tadpoles, they grow for four months in their mother’s back, safe from any threats and predators (via National Geographic).

Koalas have human-like fingerprints (and are kind of disgusting)

Koala looking at camera while eating

If you placed human fingerprints next to a koala’s, even a forensic print analyst would have trouble telling man from marsupial. As LiveScience explains, koala fingerprints look remarkably human. While it’s not surprising that chimpanzees and gorillas have fingerprints, the fact that primates and koalas’ forebears started evolving separately in the Cretaceous period makes it weird for these eucalyptus-munching marsupials to have human-like fingerprints. Experts aren’t completely sure what koalas’ fingerprints are for, especially since most of their close mammalian relatives don’t have them. However, the popular theory is that their fingerprints help them get a better grip of eucalyptus tree branches.

It’s amazing just how much koalas have adjusted to their diet over hundreds of thousands of years. Eucalyptus leaves don’t have much caloric value, so the koala spends only about two hours a day awake (via National Geographic). Additionally, eucalyptus leaves are too toxic for other animals to eat, but koalas’ bodies are capable of quickly expelling the toxins. And how do they develop this useful ability, you ask? Why, by eating their mothers’ fecal matter, of course! For a few weeks of their development, koala young (joeys) consume their mom’s anal discharge: a mix of solid fecal matter and a protein-rich, gut-bacteria-filled substance called pap (via PBS NOVA).

Oh, and try not to get peed on by a koala, because you can get the koala version of chlamydia that way.

This wasp stuffs its nest with spiders (and sometimes ants)

Spider-eating bone-house wasp on white background

Discovered in China’s Jiangxi Province, the spider-eating bone-house wasp is somehow even more horrifying than its name suggests. As Wired reports, adults of this species don’t really eat spiders and actually prefer nectar and pollen. Instead, they catch spiders to feed their larvae.

Before laying an egg, the wasp mom flies off to find some eight-legged baby food. Upon finding an arachnid target, she stings it with powerful venom that paralyzes but doesn’t kill it. She then puts the incapacitated spider in her nest and lays her egg. Thus, by the time the young one hatches, a big, still-breathing buffet is already waiting for it (via ABC News).

Researchers found other interesting surprises in the nests they studied. In some of them, the entry compartments were lined with the bodies of "aggressive, large-bodied" ants, according to a 2014 paper. This technique (called anting) isn’t exactly unique, though. Other animals, including some birds, use the scent of ants’ corpses to put off potential threats and parasites from their homes.

Octopuses are shockingly smart (and quite creepy)

Blue octopus lying on the sand

A century ago, England’s Brighton Aquarium had a disappearing fish problem. Custodians noticed that they were losing lumpfish at a seemingly steady rate. After a few days (and a few more lost lumpfish), they discovered the culprit: an octopus. The crafty cephalopod had realized it could sneak out at night, grab a quick snack from the lumpfish tank, and crawl right back into its own tank, with no one the wiser (via Scientific American).

Over the years, captive octopuses have demonstrated a surprising level of cognitive ability. In 2009, a two-spotted octopus at California’s Santa Monica Pier Aquarium apparently figured out how to take apart a water recycling valve. This resulted in a 200-gallon-flood of seawater all over the flooring, the LA Times reported. There have also been numerous accounts of octopuses in captivity learning how to use light bulbs for target practice, causing their aquariums to overflow, and even shooting water at people they recognize, according to the Washington Post.

According to experts, the secret to octopus intelligence likely lies in the abundance of neurons in their tentacles. This enables them to have exceptional control and sensitivity, a necessity for an organism with such a complicated, unwieldy body to operate (via the Guardian). This, combined with their incredible malleability, makes octopuses top-tier escape artists — and possibly far more intelligent than many of us realize.