Buzz
One of the body's most vital organs, yet often neglected and abused, is our skin. We seldom stop to appreciate this essential protective layer that encases all our organs and bodily fluids. Think of skin as the tortilla holding the fillings of an enchilada in place. It’s part of the 'integumentary system,' which also includes hair, nails, feathers, hooves, and more.
Our skin protects us from parasites and tiny invaders, while offering us an incredible sense of touch to explore the world. Throughout the animal kingdom, skin takes on many shapes, sizes, and properties (for instance, narwhal skin contains as much vitamin C as an orange). Some skins are so remarkable, they almost seem to possess superhuman qualities.
10 Crocodiles Can Sense You Swimming
Crocodilians are a tough, stubborn group of creatures, equipped with both armor and weaponry to support their tough demeanor. Their skin is renowned for its durability, and is still highly sought after today for use in boots and apparel. Surprisingly, their skin is also extremely sensitive. Along with having one of the toughest skins on Earth, crocodilians possess a unique set of sensors that no other animal has.
To begin with, their face is ‘more sensitive to pressure and vibration than human fingertips.’ This is considered one of the most refined senses of touch in the animal kingdom. Pretty impressive for a reptile that appears to be nothing more than a tough, scaly hide. The bumps around their jaw and down their sides are capable of detecting the faintest movements in the water. This helps them strike at prey with pinpoint accuracy in their aquatic environment.
They also have a wealth of sensors around their mouth and teeth. A mother crocodile can delicately open an egg of one of her hatchlings and carry it into the water, all using her highly sensitive mouth. But that’s not all—crocodiles have chemical receptors embedded in their skin. Scientists believe these receptors help them detect prey or suitable environments.
9 Sperm Whale Skin is Exceptionally Thick
There are some incredibly tough animals out there with exceptionally thick hides. Crocodiles, for example, have famously durable skin. Rhino leather is also known for its thickness and resilience. Some sources online even claim that the whale shark has the thickest skin in the animal kingdom, reaching an impressive 15 centimeters (6″) in thickness!
However, that’s still nowhere near as dense and substantial as the skin of a sperm whale. The skin of Moby Dick can reach up to 35 centimeters thick—nearly 14 inches. That’s over a foot of thickness! When you consider that sperm whales hunt giant and colossal squid, with their sharp tentacles, it makes sense that such thick skin is necessary.
Interestingly, sperm whales also possess the largest teeth and the biggest brains (Link6) of any animal. To put things in perspective, the megalodon, the largest shark ever to exist, had teeth that measured around 17 centimeters (7″) long. Sperm whales have teeth of similar size.
8 African Spiny Mice Are Experts in Regeneration
While some animals are known for their tough or thick skin, the African spiny mouse has neither. In fact, this unremarkable rodent possesses some of the thinnest skin in the animal kingdom. Yet, despite this, it boasts one of the most remarkable abilities in nature.
The delicate skin of the African spiny mouse is packed with a high concentration of hair follicles. With less connective tissue than typical skin, it tears apart with ease. In fact, it’s 77 percent easier to tear off the skin of a spiny mouse than that of a regular mouse. This means two things: First, the spiny mouse has a reliable way to escape predators—if it’s grabbed, its skin simply peels off. Second, somewhere out there, there’s a researcher whose job involves peeling the skin off mice.
But does skin that easily tears off actually serve as a good defense? After all, skin is pretty important, right? Fortunately, the African spiny mouse has a remarkable healing ability. It can regenerate skin, hair follicles, sweat glands, and cartilage in just a few days, without any scarring. In fact, a wound can shrink by as much as 64 percent in a single day. So, while ripping the skin off this rodent might seem unsettling, it doesn’t really affect the mouse at all.
7 Cephalopod Skin is Composed of Eyes
Octopuses, cuttlefish, and their relatives boast several incredible traits, but none are as mind-blowing as their skin. We’ve already explored how these creatures can change their skin in the blink of an eye to blend into nearly any background. And we’re not just talking about changing color, but also altering texture and patterns. No other creature on Earth can play the game of hide and seek like the soft-bodied cephalopods. They literally vanish into their surroundings. And scientists are still baffled by how they do it. While they’ve figured out the basic mechanics behind how cephalopods change color and patterns, that’s only the surface of the mystery.
The real puzzle is, how do cephalopods gather enough information about their environment to match it so precisely? Especially since they are color-blind. Octopuses and cuttlefish can perfectly match the color of their surroundings even though they cannot see those colors.
It’s a mystery, but new studies suggest something extraordinary. It’s likely that cephalopods can see with their skin! Opsin is a protein responsible for photoreception, and it’s found in the eyes of all creatures that have them. From cows to fruit flies, jellyfish to humans, we all owe our ability to see to opsin. Cuttlefish, naturally, have opsin in their eyes, but they also have it in their skin.
Having light-detecting cells across their entire body could explain how these animals perfectly match their environment. If they can perceive everything around them, they can easily adjust their colors and patterns to blend in.
And as unbelievable as it may seem, cephalopods are not the only creatures with this ability. Sea urchins can do it too. Some scientists believe that sea urchins can even perceive images through the light-sensing opsin spread across their bodies, despite being nearly brainless.
6 The Thorny Devil is Like a Living Paper Towel
The moloch, also known as the thorny devil, is a peculiar lizard that seems like a relic from the age of dinosaurs. Native to the deserts of Australia, these creatures are rarely bothered because their entire body is covered in menacing spikes. The moloch's diet consists solely of ants, and it has developed a range of fascinating adaptations and survival strategies suited for such a harsh environment. However, perhaps the most astonishing of all is how it acquires water.
The thorny devil can drink using its feet—or essentially any part of its body—thanks to its extremely hydrophobic skin. Its rough, jagged skin is covered in microscopic grooves and ridges designed to “wick up” water, essentially drawing moisture upward. It works similarly to what happens when you dip the corner of a paper towel in water. The water climbs up the towel, seemingly defying gravity. This same process happens with the thorny devil.
The skin relies on capillary action, where liquids move through tiny spaces due to intermolecular forces. The water is absorbed and stored in the skin, and then, through mechanisms that are not fully understood, the thorny devil uses some jaw or tongue movements to pump this water from pockets on its face into its mouth.
The thorny devil’s entire body consists of microscopic straws that all funnel water toward its mouth. Imagine being able to drink soup just by standing in it! Well, the moloch has made that dream a reality. (Don’t deny it: You’ve definitely dreamed of this.)
5 Giraffes Have Their Own Built-In Air Conditioning
In the hot and dry climates of Africa, giraffes face significant challenges. While lions relax in the shade, elephants coat themselves with mud, and hippos lounge in the water, giraffes can’t do any of these things. Sometimes, they even struggle to find shade because they’re as tall as many of the trees. So, how does the world’s tallest land animal stay cool? Air conditioner skin.
Giraffes have a few tricks for handling the heat. Like camels, giraffes don’t sweat or pant. While they can sweat and pant if necessary, they prefer not to. Conserving water is vital for an animal that has to bend down 5.5 meters (15′) into crocodile-infested waters just to drink. Instead, they raise their body temperature by 3 to 10 degrees. By staying slightly warmer than the surrounding air, they avoid sweating altogether.
Despite their incredible flexibility, giraffes must be able to release heat or they’d overheat in the sun. This is where their spots come in. Not only do they help with camouflage, but researchers have discovered that a giraffe’s spots function as thermal windows.
Each spot is surrounded by a large blood vessel, with a network of smaller vessels beneath it. Giraffes can direct warm blood to these spots, which are better at conducting heat because of their dark color. By positioning themselves in a breeze or moving out of the direct sun, they can release the excess heat. Additionally, their long necks give them more surface area relative to their body size, meaning they have more skin than other animals of similar weight.
With the ability to pump plenty of blood to their skin and ample skin to work with, giraffes are equipped with a heat exchange system that helps them thrive in extremely dry and hot environments, unlike the rest of us, who would be sweating profusely.
4 Zebra Stripes Confuse Insects
Why do zebras have stripes? Most people assume it’s to confuse predators. A herd of black and white stripes could make it hard to tell one animal from another. While that seems plausible, it’s never been conclusively proven. It might be true, but for now, it remains a theory.
Military studies have shown that it’s harder to gauge the speed of a target with highly contrasting colors. In fact, zebra patterns were used in WWII’s dazzle camouflage on warships. So, perhaps zebras are harder to catch when they run. Another interesting fact is that each zebra has unique stripes, which they use to recognize one another. These distinctive markings likely have multiple purposes.
One of the most intriguing uses of zebra stripes is as an insect deterrent. It’s known that flies are less attracted to lighter-colored coats than darker ones. Horses with light coats are more vulnerable to skin cancer and predators, but they don't have to deal with as many pesky bloodsuckers.
Recent studies have shown that biting insects, like horse flies, are less likely to target a black-and-white pattern such as the zebra’s. Given that bugs in Africa can carry dangerous diseases, having an effective defense makes sense. The secret behind the stripes lies in polarized light. Light travels in different directions, and some animals, such as insects, can detect this polarization. Many bugs are attracted to horizontally polarized light, as it’s often associated with water.
Horse hides are particularly good at polarizing light, while white fur depolarizes it. The alternating black-and-white stripes of a zebra create a confusing pattern of polarized light that insects find baffling. This chemical-free repellent takes advantage of a part of the light spectrum that most animals, including insects, can’t even see.
3. Green Sea Slugs Master the Art of Photosynthesis
The green sea slug, a close relative of the common snail, glides along the shallow shores of the Americas, resembling a damp leaf. This aquatic creature feeds exclusively on algae, and after a few hearty meals, it can stop eating altogether. From then on, it sustains itself solely on sunlight, much like a plant.
One of the few animals on Earth capable of photosynthesis, the green sea slug achieves this by stealing the tools from the algae it consumes: the green, photosynthesizing organelles known as chloroplasts. It stores these chloroplasts in its own skin cells, effectively turning itself into a solar-powered organism. Impressive, right? However, eventually, the chlorophyll in these structures depletes.
Luckily, the green sea slug has a workaround. It’s able to generate more chlorophyll on its own. It seems almost impossible, but somehow, the slug has incorporated enough of the algae's DNA into its own genetic makeup to produce chlorophyll on its own.
Once the slug has harvested enough chloroplasts to store its chlorophyll, it can survive solely on sunlight. It no longer needs to eat or produce waste. Imagine if we ate a massive salad, then never had to worry about food or toilet paper again. That's the green sea slug's life after it's powered up.
2. Chameleons Understand What Different Predators See
We've previously explored chameleons and their remarkable ability to change color. These color shifts serve several purposes: communication between chameleons, temperature regulation, and camouflage to evade predators. But new research reveals that chameleons are far more advanced than we once realized.
When a predator lurks nearby, chameleons don’t just randomly turn green and hope for the best. Studies on the Smith’s dwarf chameleon (the rarest of all) show that these clever reptiles adjust their camouflage based on the specific types of predators they face.
Researchers discovered that when the fiscal shrike (a predatory bird) appears, the Smith’s dwarf chameleon adjusts its color and pattern to blend in more with the background. And given that shrikes have a rather grim habit of impaling their prey on thorns to die a slow, agonizing death, it’s probably wise for the chameleon to disguise itself as effectively as possible.
However, when a boomslang snake slithers by, the chameleon doesn’t make as much of an effort. Spectrometer analysis revealed why. Despite its lackluster camouflage, the chameleon was still better hidden from the snake’s vision than from the bird’s. This is because the snake’s eyesight isn’t as sharp. It’s as if the chameleon instinctively knows how each predator sees and adjusts its efforts accordingly—more energy is spent hiding from the bird, while less is needed for the snake. This marks the first time an animal has been shown to adapt its camouflage based on who is watching it.
1. Bornean Flat-headed Frogs Are Lungless
The Bornean flat-headed frog can’t croak, chirp, or even hiss, because it lacks lungs. It also has no gills. In fact, it is one of the rare tetrapods on Earth that absorbs all of its oxygen through its skin.
Lungs have a purpose, and for good reason. Breathing through skin isn’t the most efficient method. Luckily for these frogs, they have a low metabolic rate, meaning they don’t need to do much in the first place. Additionally, their flattened bodies provide a large surface area. They also reside in cold water, which holds more oxygen (if you need proof, just ask a penguin about why fishing is so good in the Arctic).
The fast-moving river, splashing over rocks, creates a bubbly, white-water effect that provides plenty of dissolved oxygen for these skin-breathing amphibians. As for why they’ve evolved without lungs, researchers can only guess. Perhaps carrying an air bladder in a rushing current would just send you tumbling downstream. This might be an adaptation tailored to their very specific environment.
The unfortunate downside is that pollution is killing them off. On the bright side, they don’t have to worry about lung cancer.
