Buzz
Humans possess a wide range of skills. Some of us are skilled jugglers, others can master a guitar, and some even juggle guitars (probably). But most of what we do requires the coordination of our brains and hands. This limits us from achieving feats like contorting our bodies into knots, liquefying ourselves to squeeze through tight spaces, or swallowing a guitar (unless we experience some awful juggling mishap). These remarkable abilities belong to the animal kingdom, particularly the incredible underwater creatures featured here.
10. Black Swallowers Feast on Giant Prey
The eerie black swallower boasts an extraordinary talent, easily identified by the massive stomach pouch that hangs beneath its body. Chiasmodon niger exhibits many of the terrifying traits common to deep-sea fish, such as bulging black eyes and monstrous teeth. However, it is the fish’s remarkable ability to consume prey whole that truly sets it apart. When the black swallower spots something appetizing, it lunges forward, clamping down, and gradually swallows the entire prey by sliding its jaws over the victim.
It’s not picky about its meals, and it can consume prey up to twice its size and more than 10 times its weight. Its stomach stretches so much that it becomes translucent, allowing you to see the remains of its last meal being digested. The digestion process is so slow that it often can’t fully process its larger meals before they begin to rot. This causes gas to fill the stomach, transforming the fish into a balloon. These bloated black swallowers are the ones that end up floating to the surface, and they are the ones we encounter most frequently.
9. Sea Slugs Can Harness the Power of the Sun
The sea slug Elysia chlorotica possesses an extraordinary ability found in no other animal: it can perform photosynthesis to create its own food using sunlight. Its ancestors lived on algae, and the slug has developed the remarkable ability to steal chloroplasts—the organelles responsible for photosynthesis—from algae, integrating them into its own cells. This gives the slug its vibrant green color, earning it the nickname 'leaves that crawl.'
Even more astonishing, the slug has also taken genes from the algae, enabling it to produce its own chloroplasts. Research has even found these genes in juvenile slugs that have never consumed algae. In a surprising twist, some scientists have discovered that these slugs can survive for long periods without food in complete darkness, suggesting that photosynthesis may not be the sole factor in their survival. Regardless, this photosynthetic ability remains an exceptional and unparalleled skill in the animal kingdom.
8. Planarians Regenerate More Effectively Than Wolverine
Planarians, a species of freshwater flatworm, are famous for their incredible regenerative capabilities. These creatures are renowned for two extraordinary feats. If you sever the head of a planarian, it will regenerate a completely new one. This alone is a remarkable trait, but what’s even more fascinating is that the new head retains the memories that were present before the original was removed.
In one experiment, scientists trained planarians to tolerate light, something they naturally avoid, before decapitating them. Within two weeks, the worms grew back their heads but still remembered how to endure light exposure. While the exact cause remains unclear, the researchers speculate that this memory retention could be linked to changes in the worm's DNA or an as-yet-undiscovered biological process.
Another group of researchers discovered that a single cell has the remarkable ability to regenerate an entire body. They exposed a flatworm to intense radiation, which destroyed its tissues and prevented its cells from dividing properly. Then, they injected one cell from a healthy adult flatworm, which was able to regenerate every single part of the creature. This demonstrates that adult stem cells in flatworms can transform into any body part, unlike adult human stem cells, which have more limited capabilities.
7. Hagfish Can Tie Themselves Into Knots
We’ve previously mentioned hagfish, but their 300-million-year-long existence has provided ample time to develop multiple fascinating traits. One such unique ability of these slimy, not-quite-fish creatures is their capacity to tie themselves into knots—a skill that proves invaluable both for defense and capturing prey.
When hunting, hagfish search for fish burrows. Upon finding a fish hiding inside, they dive headfirst into the hole to drag it out. However, sticking their head into a tunnel while their tail flails about makes it challenging to catch a fish that doesn't want to be dinner. To make this easier, the hagfish ties its tail into a knot that’s larger than the hole, providing a stable anchor to pull itself—and its meal—out of the burrow.
Hagfish have also turned this knot-tying ability into a clever escape maneuver. When held at one end, they knot their free end and push the knot up their body. As the knot reaches the predator’s grip, it pushes against the captor, allowing the hagfish to wriggle free and escape.
6. Sea Cucumbers Can Turn Themselves Into Liquid
Sea cucumbers are known for their unique defense mechanism, which we’ve mentioned before. When threatened, they eject their internal organs and later regenerate them. But that’s not all—sea cucumbers have a second extraordinary defense tactic: they can liquefy themselves. They do this by disconnecting the bonds that hold their cells together, allowing their bodies to flow into tight spaces.
Once they reach their desired destination, the sea cucumber can solidify back into its original form, making it difficult to remove from hiding. This ability is so extreme that it’s even possible for a sea cucumber to liquefy itself to the point of death. It would turn into a gooey substance, flowing right through your fingers if you were holding it (at which point, you would likely exclaim to aquarium staff, 'I swear I didn’t do anything!').
5. Mudskippers Can Climb Trees
There’s a widely circulated quote often attributed to Einstein: 'Everybody is a genius. But if you judge a fish by its ability to climb a tree, it will live its whole life believing that it is stupid.' If you search for 'Einstein fish tree' on Google, you’ll encounter thousands of motivational posters featuring his face and this quote, despite the fact that Einstein never actually said it.
Next time you see one of these posters shared by a friend, feel free to show them a video of a fish climbing a tree. The fish in question is the mudskipper, a remarkable species that spends a large part of its life outside of the water. It thrives in mangrove areas and has no trouble hauling itself up a log or branch. Using its pelvic fins as a type of suction cup, it can attach itself and then pull itself upward using its pectoral fins.
Mudskippers also have special sacs around their gills that allow them to hold a breath of water, similar to how we hold a breath of air. They climb trees primarily to remain out of the water during high tides.
4. Archerfish Are Skilled Marksmen Who Shoot Down Prey
Contrary to what Hollywood might have led you to believe, talented archers aren't always rebellious young women or Jeremy Renner. The archerfish is a small tropical fish that primarily feeds on insects. It earns its name from its remarkable technique of capturing prey. Typically no longer than 10 centimeters (4 inches), this fish can shoot a jet of water as far as 2 meters (6 feet) to knock insects off plants hanging near the water’s surface.
The archerfish is not just accurate, but also capable of hitting its tiny targets in the dark with enough force to knock them into the water. To create the jets, the fish presses its tongue against a groove in its mouth, resembling the action of a gun’s barrel. The water speeds up as it leaves the mouth, allowing all the water to reach the target at once, delivering six times the impact force the fish’s muscles alone could muster.
3. The Tigerfish Snatches Birds Out of the Air
The tigerfish is aptly named after its ferocious predator cousin, the tiger, known for its sharp teeth and lethal nature. This African fish, often compared to the piranha, uses its razor-sharp jaws to tear apart its prey. Unlike the piranha, however, the tigerfish comes in a much larger variety: the goliath tigerfish, which can weigh up to 50 kg (110 lb) and even eat crocodiles.
However, it is the hunting prowess of the smaller tigerfish that earned it a spot on this list. Recently, researchers filmed one of these fish catching birds. While many fish might feast on birds floating on the water’s surface, this tigerfish in a South African lake was filmed leaping out of the water and snatching a swallow mid-flight.
Although no one has yet witnessed the goliath tigerfish exhibiting this behavior, we’re likely going to avoid taking helicopter rides over African lakes for the time being, just to be safe.
2. The Pirate Perch Masters the Art of Camouflage
The pirate perch is an intriguing species. When it’s young, its anus is in the typical position you'd expect, but as it grows, this body part relocates just beneath its chin. However, it’s not the migrating anus that earned it a spot on this list. And, just in case we haven’t used the word ‘anus’ enough already, we’d like to mention that the scientific name of this fish is A. sayanus.
In a study examining the behavior of beetles and frogs in response to predatory fish, scientists discovered an additional fascinating trait of the pirate perch. When given a choice of ponds to live and breed in, the beetles and frogs instinctively avoided those with fish that might target them for dinner—except for one case. The potential prey were perfectly happy to settle in ponds where pirate perch were present.
The researchers are uncertain whether the pirate perch is masking its chemical signature, mimicking another creature, or if some other unknown factor is at play. However, one thing is clear: the pirate perch has an unparalleled ability to conceal its presence, a skill that sets it apart from other fish.
1. The Teddy Bear Crab Crafts Living Weapons
The teddy bear crab is a small crustacean covered in fluffy white bristles. While the appearance of a furry crab is fascinating on its own, the species Polydectus cupulifer demonstrates a highly unusual behavior. It picks up stinging anemones—one in each claw—and uses them as weapons. However, this crab doesn't simply carry around its anemone companions. It has the ability to identify which anemones are useful and positions them precisely to strike with the optimal part of the weapon.
The anemone is not just a tool for fending off predators; it also serves as a food source. The crab will often collect nourishment from its ‘partner,’ even going so far as to reach inside the anemone’s digestive system to retrieve any food the anemone has already consumed.
