From winged dragons and unicorns, to Bigfoot and the Chupacabra, we humans have imagined a vast menagerie of animals that don't actually exist. We tend to be so engrossed in fantasy creatures that we don't pay much attention to many of the 7.7 million different animal species that scientists estimate really live on our planet [source: Science Daily].
Some are so colorful and bizarre that they almost seem as if some overeager fabulist made them up. Take, for example, the golden lion tamarin, whose lush, resplendent mane and scowling visage make it look like a miniature version of one of those late-1980s heavy metal rockers on MTV. Then there's the axolotl, which uses its stubby legs to crawl along the bottoms of lakebeds, and the dingiso, a tiny kangaroo-like creature that hops around on tree branches instead of on the ground.
But as we revel in this biodiversity, we also should remember that many of the world's most incredible creatures are threatened by deforestation, climate change and other human-induced activities in the environment. WWF warns we're losing hundreds and possibly thousands of species each year, an extinction rate that far exceeds the ordinary ebb and flow of nature [source: WWF]. It's up to us to save them.
In that spirit, here are 10 animal species so strange and wonderful that they seem make-believe. And many are in danger of extinction.
Imagine a tiny black-and-white kangaroo that lives in trees, and you've got the basic description of the dingiso (Dendrolagus mbaiso). The animal, which resides in the mountainous rainforests of New Guinea, grows to as much as 2.5 feet (76 centimeters) in length, possesses a long tail, well-developed hindquarters and a habit of moving both its hind feet at the same time in a hopping gait, just like the bigger Australian kangaroos that we're all familiar with.
The dingiso sports curved nails and cushioned pads lined with rough skin on its large feet, which enable it to get a grip on tree trunks and branches, where it uses its long tail for balance as it climbs. Like the kangaroo, the female dingiso has a pouch on its abdomen, where its young ride as they suckle milk from one of its four breasts. Sadly, their numbers are declining due to loss of habitat, hunters and a low birthrate [source: Arkive].
9 Komodo Dragon
In the ancient world and right up through the Middle Ages, people told tales of monstrous giant reptiles called dragons, which sometimes sported bat wings and barbed tails, and wreaked carnage by breathing fire [source: Encyclopaedia Britannica]. But that macabre fantasy creature turns out to have a real-life cousin.
In 1912, naturalists discovered the Komodo dragon (Varanus komodoensis), a lizard from Indonesia that grows up to 11 feet (3.5 meters) in length. These reptiles are plenty scary in their own right. They're carnivorous hunters, and on occasion they've even dined upon humans. While they lack fiery breath, they exhale something nearly as deadly — a virulent bacteria, which infects wounds caused by the dragon's teeth and causes them to rot and fester [source: Slifkin and Slifkin].
8 Giant Squid
Ancient lore is full of multi-limbed sea monsters such as the Scylla of Homer's epic poem "The Odyssey," which had 12 feet, six heads and a bark like a dog [source: Encyclopaedia Britannica]. But in 1873, scientists got their first inkling of a real-life creature that resembled this one, when a Newfoundland fisherman caught a large tentacle-laden sea animal inadvertently and sold it to an amateur naturalist, the Rev. Moses Harvey.
The giant squid (genus: Architeuthis), can grow to up to 43 feet (13 meters) in length, and weigh as much as a ton (907 kilograms). It has two eyes, a beak, eight arms, and two feeding tentacles equipped with sharp-toothed suckers that can grab prey as much as 33 feet (10 meters) away. Because the immense creature lives deep underwater, humans never saw a living one until 2006, when a research team in the Pacific Ocean south of Japan managed to hook a 24-foot (7.3 meter)-long specimen and pull it to the ocean surface [source: Smithsonian].
7 Golden Lion Tamarin
You probably won't see one as a guest judge on "American Idol" any time soon, but golden lion tamarins (Leontopithecus rosalia)are the rock stars of the Amazonian rain forest. The diminutive creatures, whose bodies can stretch to nearly 9 inches (22 centimeters) in length plus a tail of up to 13.5 inches (34 centimeters), have a striking mane of lush, golden fur, which frames a gray-black face with startlingly anthropomorphic features.
These primates, which spend most of their lives in the trees, use their long fingers to climb and swing from branch to branch, and to snare insects, fruit, lizards and birds for food. Both genders split responsibility for raising their young, with males sometimes carrying babies on their backs between feedings, as if they were human yuppie dads. (Their young are usually twins.) Unfortunately, these magnificent creatures are critically endangered due to logging and agricultural expansion that are destroying their habitat [source: National Geographic].
The axolotl (Ambystoma mexicanum), also known as the "water monster" and the "Mexican walking fish," is a peculiar but versatile foot-long (30-centimeter-long) aquatic creature that can use its four stubby legs to drag itself along lake bottoms, or else swim along the surface. It also has a strange, lizard-like face with plume-like gills and a mouth that seems to curl into a smile.
Even so, the axolotl, which feeds on aquatic insects, small fish and crustaceans, doesn't have a lot to be happy about these days. The fish is indigenous to the Xochomilco network of lakes and canals around Mexico City, but those waters have become so polluted due to urban sprawl that a 2013 study from Mexico's National Autonomous University failed to turn up any specimens after four months of searching. While axolotls survive in aquariums, water tanks and research labs, scientists are still hopeful that axolotls haven't completely vanished in the wild [source: Associated Press].
5 Giant Oarfish
Slithery giant sea serpents have inhabited the nightmares of sailors since ancient times. It turns out, however, that the real-life creature that resembles them most closely, the giant oarfish (Regalecus glesne), actually isn't a snake but rather the largest bony fish in the sea. The rare creatures, which are found in tropical and temperate waters at depths as low as 3,000 feet (914 meters), have shiny, silvery bodies, bright red crests on their heads, and toothless mouths, which they use to suck up and filter small fish, shrimp and other invertebrates. Relatively little is known about the fish, which probably only come to the surface when they are injured or dying [source: NOAA].
Therefore, marine scientists were excited when, in October 2013, the bodies of two oarfish — including a 14-foot (4.6 meter)- long female with ovaries full of eggs — were found off the coast of Southern California. This provided a precious opportunity to study the elusive animals [source: Quenqua].
If you can imagine a creature that's a cross between a donkey and a zebra that walks like a giraffe, then you've got a pretty good mental picture of the okapi (Okapia johnstoni). The strange-looking animal, which is about 8 feet (2.5 meters) long and stands about 5 feet (1.5 meters) tall from hoof to shoulder, lives in the dense tropical rain forests of northeastern Democratic Republic of the Congo. Its bizarre coloration — it has a brown body and legs and hindquarters covered with an array of horizontal black-and-white stripes — enables it to disappear into its usual backdrop of dense vegetation and lighter-colored rotting leaves on the forest floor.
The okapi mimics a giraffe's rolling gait by stepping with the front and hind legs on the same side of the body, instead of using the legs from the opposite sides, as other grazing animals tend to do. It also has a long, black tongue, which it uses for plucking buds, leaves and branches from trees and shrubs [source: Animal Diversity Web]. Sadly, this exotic creature may be in danger of disappearing, with a mere 20,000 existing in the wild [source: Okapiconsevation.org].
This semiaquatic, fur-covered, duck-billed, web-footed mammal that lays eggs seems to have been assembled from bits of other animals. Hailing from Australia, the platypus is about 2 feet (61 centimeters) in length and weighs just 3.5 pounds (1.5 kilograms) [source: ADW]. In fact, the platypus (Ornithorhynchus anatinus) is so odd that when English naturalists first obtained a carcass for study in 1799 from New South Wales Gov. John Hunter, they worried that it might be a hoax foisted upon them by a mischievous taxidermist [source: Museum of Hoaxes].
The platypus is a forager that scoops up insects, larvae, shellfish, worms and gravel with its bill from the mud on the bottom of streams. It stores its finds within cheek pouches until it reaches the surface and then uses the gravel to mash up the food for eating – a platypus has no teeth. Despite its seemingly awkward design, the creature turns out to be a surprisingly adept underwater swimmer, thanks to its webbed feet and beaver-like tail [source: National Geographic].
2. Devil Bird
In Sri Lankan folklore, a woman whose child was murdered by her husband went mad and ran off into the jungle to commit suicide. After her death, the gods transformed her into a creature called the ulama, or devil bird, whose horrible, human-sounding wail in the distance is a portent that something terrible is about to happen [source: Dole].
But was this a real animal? In the 1950s, ornithologist George Morton Henry, author of a definitive volume on the birds of Sri Lanka, decided that the devil bird actually was the spot-bellied eagle owl (Bubo nipalensis blighi)[source: Eberhart]. This predatory bird, which is also known as the forest eagle owl, is found in a swath of south Asia stretching from India to Burma. It is about 21 inches (53 centimeters) in length and has heart-shaped spots and prominent black-and-white ear tufts that give it a suitably eerie appearance. But people who are fearful of it shouldn't worry, because it eats only game birds (like pheasants), reptiles and fish [source: Harrison].
1 Tasmanian Devil
Some might think the Tasmanian devil is a fictional creature, cooked up by an imaginative animator for the Warner Bros. "Looney Tunes" shorts. But it's actually a real animal, Sarcophilus harrisii, which is indigenous to Tasmania, an island to the south of the Australian mainland.
The size of Tasmanian devils varies considerably, depending on diet, habitat and age, but large males can grow as long as 2.5 feet (80 centimeters) and weigh as much as 26 pounds (12 kilograms). The devil is a stocky animal with brownish-black fur, white throat patches and spots on its sides and backside, pink snout and a big powerful head and jaw. The latter enables the scavenger to gnaw on the already dead carcasses of wombats, wallabies, sheep and rabbits, though devils also will eat insects, larvae, snakes and vegetation when the opportunity presents itself.