7 Crocodilian Species That Are Dangerous to Humans

Black Caiman (Melancholics Niger)

The black caiman resides in northern South America and can be found over much of the Amazon River basin from Peru and Ecuador eastward to Guyana and Suriname. Black caimans have a broad diet, feeding on fish and other reptiles as well as rodents such as the capybara (which can grow as large as 4 feet [1.25 meters] long). Adult male black caimans often grow longer than 13 feet (about 4 meters); larger specimens have been known to attack people. The Worldwide Crocodilian Attack Database (CrocBITE), which is associated with Australia’s Charles Darwin University, notes that between January 2008 and October 2013, black caimans were involved in 43 attacks on people, and fewer than one-fifth of those were fatal.

 

Mugger Crocodile (Crocodiles palustris)

The mugger, or marsh, crocodile can be found in freshwater pools, wetlands, lakes, and slow-moving streams from Iran to the western fringes of Southeast Asia. It is easily recognized by its wide flat snout. Among the largest crocodile species in terms of physical size, muggers can grow to 13 to 16.5 feet (about 4 to 5 meters) as adults. Although they tend to feed on fish and reptiles, some have fed on larger prey, such as deer. According to CrocBITE, muggers attacked 110 people between 2008 and 2013, with approximately one-third of those attacks resulting in the death of the victims.

 

American Crocodile (Crocodylus acutus)

The American crocodile, also called the Central American alligator, inhabits a wide range of aquatic habitats from southern Florida and Mexico south through the Caribbean islands and Central America to northern South America. It is no stranger to saline environments, having been observed in estuaries filled with brackish water. Adult males grow to approximately 16.5 feet (about 5 meters) in length. American crocodiles prefer smaller vertebrates as prey, but reports of attacks on people are not uncommon. CrocBITE notes that 90 people were attacked between 2008 and 2013, which resulted in approximately 20 deaths.

 

Gharial (Gavialis gangeticus)

The gharial, or gavial, inhabits the rivers of northern India and Nepal. It is distinguished by its long and very slender sharp-toothed jaws, which it sweeps sideways in order to catch fish, its main prey. The gharial normally attains a length of about 12 to 15 feet (3.7 to 4.6 meters). It does not attack humans but apparently does feed on corpses set afloat in funeral ceremonies on the Ganges River.

 

American Alligator (Alligator mississippiensis)

American alligators (or “gators”) are native to the Gulf Coast region of the United States and can be found in freshwater environments ranging from lakes and streams to swamps, marshes, and other wetlands; however, some have been observed in saltier habitats such as mangrove swamps. Most alligators are smaller than their crocodile cousins, with adult males generally growing to between 13 and 15 feet (4 and 4.5 meters). Between 2000 and 2007, alligator attacks averaged just under 11 per year in Florida, though deaths from those attacks were less than 10%. Between 1948 and 2005, wildlife officials documented 379 alligator attacks on people, which resulted in 17 deaths. Interestingly, they also noted that most of those events did not seem to start with the alligator but rather began with people attempting to pick up, capture, or otherwise handle the animal.  

 

Saltwater Crocodile (Crocodylus porosus)

 The saltwater crocodile (also called the estuarian crocodile, or “Saltie”) lives primarily in Southeast Asia, from southern India through Australia’s northern fringe. Despite their name, saltwater crocodiles are not exclusive to saltwater habitats; they are also found in brackish waters and freshwater streams and swamps. Fully grown adult males can reach more than 20 feet (about 6 meters) in length and weigh more than 1,100 pounds (roughly 500 kg). Considering only the records kept by Australia and Malaysia, the IUCN reports that between 2000 and 2007, saltwater crocodiles were responsible for nearly 30 separate attacks on people. In Australia a quarter of those attacks were fatal; in Malaysia half of the attacks resulted in the victim’s death.

 

Nile Crocodile (Crocodylus niloticus)

With a geographic home range spanning most of Africa, save the Sahara, and part of Madagascar, the Nile crocodile is at home in various habitats made up of freshwater lakes and streams and brackish waters. Although adults vary in size, most grow to reach 16.5 to almost 20 feet (roughly 5 to 6 meters) in length. The species easily claims the title of the most-dangerous crocodilian, since it is widely thought to be responsible for more than 300 attacks on people per year. 

different types of rainforest animals

1. Mountain Gorilla

 Mountain gorillas are the largest living primates on earth! Along with chimpanzees, orangutan, and bonobos, they are the closest living relatives of humans, with mountain gorillas having the most developed brain of the four. They live primarily on the lush mountain sides of national parks in Rwanda, Uganda, and the Democratic Republic of Congo in Central Africa. Mountain gorillas live in groups of roughly 30 members, with one dominant, male troop leader called a ‘silverback’ for the silver color in his coat.

 

2. Blue Morpho Butterfly

With its brilliant, iridescent blue wings, the blue morpho butterfly flutters through the rainforest canopy. The many “eyespots” on its brown underside trick predators into thinking the butterfly is a large predator.

 

 

 

 

3. Okapi

The striking okapi—the closest living relative of the giraffe—lives in the dense tropical Ituri Forest of Central Africa. A master of camouflage, its striped hindquarters and brown hide helps it “disappear” into the filtered light of the forest.

 

 

 

 

4. Brown-Throated Three-Toed Sloth

The slow-moving sloth, weighing only eight or nine pounds, lives exclusively in trees, feeding on leaves, twigs, and fruit. It moves so slowly that its fur takes on a green tinge from the algae that grows on it. It can take a month to digest a single meal.

 

 

 

5. Jaguar

Jaguars are famous for their beautiful spotted coats, which help them hide amongst the grasses, bushes, and trees where they live. The rare, all-black (melanistic) jaguar is what we commonly refer to as a black panther. Jaguars are known to eat more than 85 species of prey, including armadillos, peccaries, capybara, tapir, deer, squirrels, and birds and can even snatch fish, turtles and young caiman from the water.

 

 

6. Capybara

Bearing a strong resemblance to its guinea pig cousin, the capybara is the largest rodent on Earth, weighing in at more than 100 pounds and standing two feet tall. It lives in the dense vegetation that surrounds water, and frequently leaps in water bodies to hide from predators. It can hold its breath for up to five minutes.

 

 

7. Scarlet Macaw

One of the most iconic rainforest species, the scarlet macaw is a striking, large parrot with bright red plumage and brilliant blue and yellow wing feathers. Its powerful beak can open hard nuts and seeds. Scarlet macaws are one of the few species that mate for life.

 

8. Poison Dart Frog

One of the most brightly colored animals on the planet, the poison dart frog uses its color to warn predators of the toxic venom the lies within its skin. Indigenous cultures often use this frog’s poison to coat the tip of blow darts used for hunting.

 

 

 

 

9. Black Howler Monkey

The black howler monkey earns its moniker with the loud howl it uses to mark territory. These vocalizations, which sound like a strong wind blowing through a tunnel, can be heard up to two miles away. These monkeys live high up in tall rainforest trees in groups of 4 to 19.

 

 

 

10. Sulawesi Bear Cuscus

Named for its thick, dark, and bear-like fur, the Sulawesi bear cuscus isn't a true bear, but is actually an arboreal marsupial. Like other marsupials, the female Sulawesi bear cuscus gives birth to relatively underdeveloped offspring and carries the infant in a pouch on her belly until it is approximately eight months old and sufficiently developed for survival. They live in the undisturbed forests of Indonesia, predominantly on the island of Sulawesi.

 

 

11. Green Anaconda

The storied green anaconda is one of the largest snakes in the world, reaching over 30 feet in length, 12 inches in diameter, and weighing over 550 pounds. Due to its size, it is quite cumbersome on land, but it is stealthy in the water.

 

 

all about different animal

Koala fingerprints are so close to humans' that they could taint crime scenes.

Koalas might not seem to have a lot in common with us, but if you were to take a closer look at their hands, you'd see that they have fingerprints that are just like humans'. In fact, they're so similar when it comes to the distinctive loops and arches, that in Australia, "police feared that criminal investigations may have been hampered by koala prints," according to Ripley's Believe It or Not. Any koalas who want to commit crimes would be wise to do so wearing gloves.

Parrots will selflessly help each other out.

Parrots may be associated with pirates, but it turns out African grey parrots are nothing like the infamously greedy, treasure-seeking criminals. Instead, researchers have discovered that the colorful birds will "voluntarily help each other obtain food rewards" and perform "selfless" acts, according to a 2020 study published in Current Biology. Study co-author Auguste von Bayern noted, "African grey parrots were intrinsically motivated to help others, even if the other individual was not their friend, so they behaved very 'prosocially.'"

 

 

Ghost crabs growl using teeth in their stomachs.

Crabs may be able to intimidate other creatures with their claws, but if that's not enough, ghost crabs will growl at their enemies like a dog. However, unlike our canine friends, crabs make these fearsome noises using teeth located in their stomachs. "There are three main teeth—a medial tooth and two lateral teeth—that are essentially elongated, hard (calcified) structures. They are part of the gastric mill apparatus in the stomach, where they rub against each other to grind up food," Jennifer Taylor, from the University of California, San Diego, told Newsweek. She and her colleagues were able to nail down the source of the noise after noticing that "the crabs [were] 'growling' at" them.

The mantis shrimp has the world's fastest punch.

You might think that boxers have the most impressive jabs, hooks, and uppercuts on the planet, but it's the mantis shrimp that boasts the world's fastest punch. Traveling at about 50 mph, when a shrimp punches, its little fist of fury (which, of course, isn't a fist at all) is "accelerating faster than a .22-caliber bullet," according to Science. National Geographic shared the tale of one such small smasher, explaining that "in April 1998, an aggressive creature named Tyson smashed through the quarter-inch-thick glass wall of his cell. He was soon subdued by nervous attendants and moved to a more secure facility in Great Yarmouth. Unlike his heavyweight namesake [former professional boxer Mike Tyson], Tyson was only four inches long. But scientists have recently found that Tyson, like all his kin, can throw one of the fastest and most powerful punches in nature."

Female lions do 90 percent of the hunting.

While male lions attract their fair share of attention thanks to their impressive manes, it's the female lions who do the bulk of the work when it comes to feeding their families. "Lionesses, not male lions, do the majority of hunting for their pride," according to CBS News. "Lionesses hunt around 90 percent of the time, while the males protect their pride."

Narwhal tusks are really an "inside out" tooth.

 Narwhals are unlike most other whales because they have what appears to be a giant tusk. But that's not actually a tusk at all—what you're seeing is a tooth. Harvard University's Martin Nweeia told the BBC that the "tooth is almost like a piece of skin in the sense that it has all these sensory nerve endings," adding that it's "essentially built inside out."

 

Puffins use twigs to scratch their bodies.

Puffins surely have enough to be proud of with their beautiful beaks, but the seabirds also happen to be quite clever. According to a 2019 study published in Proceedings of the National Academy of Sciences (PNAS), Atlantic puffins in both Wales and Iceland were observed "spontaneously using a small wooden stick to scratch their bodies." Indeed, in a video shared by Science, a little puffin can be seen picking up a tiny twig before using it to scratch an itchy spot on its belly.

 

Capuchin monkeys wash their hands and feet in urine.

 

Monkeys are undeniably cute. They can also be pretty darn gross. Capuchin monkeys, for example, urinate on their hands and feet when they're feeling "randy." "We think the alpha males might use urine-washing to convey warm, fuzzy feelings to females, that their solicitation is working and that there's no need to run away," primatologist Kimran Miller told NBC News. "Or they could be doing it because they're excited." Either way, ew!

Sperm whales in the Caribbean have an accent.

 People who come from different areas around the world tend to speak with inflections, fluctuations, and patterns that are specific to their home regions. Apparently, the same can be said for whales. Researchers from Dalhousie University in Canada and the University of St. Andrews in the UK have found evidence that seems to show whales in the Caribbean have a different "accent" than whales in other oceans.

 

Some sharks glow in the dark.

Sharks boast some enviable—and terrifying—features, like their sleek design and razor-sharp teeth. And while glow-in-the-dark sharks sound like something you'd see in a sci-fi film, they're totally real, as noted in a 2019 study published in iScience. Researchers were already aware that some shark species produce a glow that only other sharks can see, but now scientists have discovered that "previously unknown small-molecule metabolites are the cause of the green glow," according to CNN. This glow "helps sharks identify each other and even fight against infection on a microbial level."

Some snails have hairy shells.

 

While it's not a secret that snails have shells, you probably didn't know that some actually have hairy shells. These hairs are rather handy to have, as they help a snail stick to wet surfaces like leaves.

 

Cowbirds use secret passwords to teach their young.

 Cowbirds lay their eggs in other bird species' nests, which means that the little ones eventually need to reconnect with their own kind when the time is right. And when that time comes, the young birds have a trick for figuring out who to reach out to. "Juvenile cowbirds readily recognize and affiliate with other cowbirds. That's because they have a secret handshake or password," according to Science Daily. To put it more simply, they use "a specific chatter call" to beckon each other.

 

 

A grizzly bear's bite is strong enough to crush a bowling ball.

Those who find themselves in the presence of a grizzly bear will surely want to stay out of reach of this animal's super sharp claws. But they'll certainly also want to keep out of the grizzly's mouth, because these creatures "have a bite-force of over 8,000,000 pascals," according to National Geographic. That means grizzly bears can literally crush a bowling ball between their jaws. Yikes!

 

Humpback whales use bubbles to hunt.

 You might think that a whale's massive size is the only edge they'd need when it comes to hunting in the open waters. But humpback whales actually team up to use a "bubble-net" technique in order to catch their prey. "Sometimes, the whales will swim in an upward spiral and blow bubbles underwater, creating a circular 'net' of bubbles that makes it harder for fish to escape," Science News reports.

 

A housefly buzzes in an F key.

 

When you hear a housefly buzzing around your home, you might be annoyed by the persistent sound. However, the next time it happens, try to soothe yourself by noting that the airborne pest is actually buzzing in an F key. How melodious!

 

Moray eels have a second pair of "Alien-style" jaws.

If you already thought that eels were kind of creepy, then this fact isn't going to make you feel any better about them. Moray eels have what's called pharyngeal jaws, which are a second pair of "Alien-style" jaws that are located in the throat and emerge to grasp prey before pulling the unfortunate meal down into the eel's gullet.

 

Slow lorises are the only venomous primates. 

They may be cute, but their bite can kill. According to Popular Science, these adorable animals secrete toxins from a gland in the crook of their inner arms. Their bites have caused anaphylactic shock and even death in humans. Better watch out!

 

Zebra stripes act as a natural bug repellant.

Cows may benefit from artificial stripes, but zebras have the real deal. One 2012 report published in the Journal of Experimental Biology suggests that zebras' black and white stripes may be an evolutionary feature to fend off harmful horsefly bites. "A zebra-striped horse model attracts far fewer horseflies than either homogeneous black, brown, grey or white equivalents," the researchers wrote

 

Wild chimps like to drink.

 

Humans aren't the only animals who enjoy a drink or two. A 2015 study published in the journal Royal Society Open Science reveals that chimpanzees in Guinea had a fondness for imbibing fermented palm sap and getting tipsy in the process.

 

Sea otters are adept at using tools.

While many scientists believe that tool use among dolphins is a relatively new phenomenon, a 2017 study published in Biology Letters suggests that otters may have been using tools for millions of years. Sea otters frequently use rocks to break open well-armored prey, such as snails.

 

A group of ferrets is called a business. 

No, it's not because they're so professional—it's a modernized form of "busyness," the word originally used to describe a group of these weasel-related mammals.

 

 

Octopuses can taste with their arms.

And yes, they are called arms, not tentacles. According to the Library of Congress, the animals can taste and grab with the suckers on their arms. Even more impressive? Octopuses are capable of moving at speeds of up to 25 miles per hour.

 

Alligators will let manatees swim ahead of them. 

In busy waters, manatees will nudge alligators to get in front, and alligators generally oblige.

 

 

 

 

Sloths can take up to a month to completely digest a single leaf.

Everything about life is slow for these sleepy mammals. Most sloths will only have a bowel movement once a week, and it can take them up to 30 days to completely digest a single leaf. For comparison, it takes the average human 12 to 48 hours to ingest, digest, and eliminate waste from food.

 

 

 

 

 

Elephants and humans have similar self-soothing techniques.

Elephant calves will suck their trunks to comfort themselves. The babies do it for the same reason humans do (it mimics the action of suckling their mothers)

 

 

 

Female bats give birth to babies that weigh up to a third of their weight.

According to Bat Conservation International, bats give birth to babies—known as pups—that can weigh as much as one-third of the mother's weight. If that doesn't sound like a lot, imagine a person giving birth to a baby that weighed 40 pounds.

 

 

Painted turtles survive winter by breathing through their butts.

Not all creatures head to warmer climates when it gets cold out, and that means they need to learn to survive in chilly conditions. Painted turtles need to adapt to frozen ponds, which restrict their access to the air above the water. They do that by breathing through their butts—specifically, the all-purpose orifice called the cloaca. Thanks to a process called cloacal respiration, the turtles are able to get oxygen directly from the water around them.

 

Otters have the world's thickest fur. 

They're thought to have up to one million hairs per square inch. Their fur consists of two layers and is designed to trap a layer of air next to their skin so their skin doesn't get wet. 

Alligators can grow for more than 30 years.

According to a 2018 study published in Copeia, alligators often haven't hit their full size until 33.

 

 

 

 

A group of owls is called a parliament.

Their legislative powers, however, are still up for debate.

 

 

 

 

 

Snow leopards don't roar.

Snow leopards have less-developed vocal cords than their fellow large cats, meaning that they can't roar, but make a purr-like sound called a chuff instead. For a 2010 study published in the Biological Journal of the Linnean Society, scientists researched why some cats have a higher-pitched meow than others. They found that it's not size that determines a kitty's call, but habitat.

 

Axolotls can regenerate their parts.

The salamanders are the only vertebrates that can replace their skin, limbs, tail, jaws, and spines at any age. On the flip side, humans can regenerate lost limb buds as embryos and fingertips as young children.

A group of rhinos is called a crash.

Individual male rhinos are referred to as bulls, and females as cows.

 

 

 

 

Squirrels will adopt orphans.

Turns out, squirrels have an intense motherly instinct. One 2010 study by researchers at the University of Guelph found that the animals will take in the orphaned pups of their late family members.
"Social animals, including lions and chimpanzees, are often surrounded by relatives, so it's not surprising that a female would adopt an orphaned family member because they have already spent a lot of time together," said lead researcher Andrew McAdam, an evolutionary biologist. "But red squirrels live in complete isolation and are very territorial. The only time they will allow another squirrel on their territory is the one day a year when the females are ready to mate or when they are nursing their pups."

Giant anteaters have two-foot tongues. 

According to National Geographic, it's the longest tongue of any known mammal. 

Deer can run up to 35 miles per hour.

 Yes, white-tailed deer can hit top speeds of 35 miles per hour. Think that's fast? Reindeer can run up to 50 miles per hour.

An octopus has three hearts.

Octopuses have two more hearts than you do. Two hearts are used to pump blood to their gills, while the third brings blood to the rest of their body. If that's not enough, they also have nine brains.

Some worms can jump.

Certain species of the Amynthas worm, which have recently been identified in the Midwestern United States, can jump and detach their tails when disturbed.

Crocodiles can live up to 100.

Nile crocodiles can live for a full century. And they can do a lot of damage over the course of those 100 years: Approximately 200 people die every year from Nile crocodile attacks. 

Tigers have striped skin.

You might think it's just their fur, but no, tigers have striped skin. And speaking of those stripes, much like our fingerprints, they're unique to every tiger. 

Vampire bat saliva keeps blood from clotting.

 Vampire bats do more than just bite their prey—they also keep the other animal's blood from clotting. Their saliva works as an anticoagulant, so that the blood can flow freely as they feed. Here's another fun fact: The protein in the anticoagulant has been nicknamed "Draculin." Spooky!

 

 

 

Wombat poop is cube-shaped.

Wombats use their droppings to warn other animals to stay off their turf. Luckily, their cube-shaped poop makes it easy to see that a spot is governed by wombats, as the little squares tend to stay put more easily than spherical droppings would.

 

Queen mole rats make other female mole rats infertile.

To ensure her dominance, the queen mole rat works to make it impossible for other female mole rats to have litters. In fact, the queen can produce a substance in her urine that renders other female mole rats infertile.

 

 

Horned lizards squirt blood from their eyes.

The horned lizard has a pretty impressive trick for evading predators. When a horned lizard finds itself in a perilous situation, it can squirt a stream of blood from its eyes. The predator then runs off, because, well, wouldn't you? 

Catfish have taught themselves how to kill pigeons.

Relax, pigeons—it's not all catfish. But yes, in southwestern France, a group of European catfish have learned to kill pigeons, launching themselves out of the water to grab the sunbathing birds.

 

Primitive crocodiles could gallop.

If you think crocodiles aren't frightening enough, consider this: They used to gallop. While modern-day crocodiles can move surprisingly fast, giant crocodiles during the Cretaceous period could use their legs to chase and kill dinosaurs.