Prehistory squeezed out an inexhaustible list of captivating creatures. Everyone already knows about the raptors, mammoths, saber-tooth tigers, and similarly legendary beasts, but that’s barely scratching the surface of nature’s creativity.

From sea lion–like whales that popped above water to give birth to the VW Beetle–sized armadillo that gave up its shell for the benefit of humanity to a terrible armored frog that snatched up cute little baby dinosaurs, the prehistoric world was teeming with fascinating but little-known life-forms.

10 Primitive Whales That Gave Birth On Land

Protocetids, the primitive whales of 50 million years ago, looked mind-blowingly goofy. They were relatively small, only about 2–5 meters (7–16 ft) long. And they had four ridiculous limbs that ended in hoofed flippers.

These weird appendages allowed creatures like Maiacetus inuus to flop about on land like a sea lion as the lineage of early whales split from their goatlike and cowlike ancestors and took to the waves.^[1]

Protocetids fed in the water but emerged onto land for other daily activities, including sleeping, mating, and giving birth.

One delectably rare fossil of a pregnant mother and her unborn calf supports the land-birth theory. The 48-million-year-old calf is positioned headfirst in the womb like land mammals whereas aquatic creatures are positioned tailfirst to avoid drowning before the end of labor.

9 Bus-Sized Crocodiles That Ruled The Seas

Machimosaurus rex was discovered within 120-million-year-old rocks on the edge of the Sahara in Tunisia in an area that was once an ocean-facing lagoon.^[2]

Like the modern crocs on Nat Geo and Science, Machimosaurus made its living as an ambush predator. It snapped up sea creatures as well as land creatures that ventured too close to the shore. And with its short, rounded teeth, it could have easily ground prehistory’s large turtles into dust.

It’s the largest sea-dwelling crocodile ever—three tons and 9 meters (30 ft) of fury—with a skull that surpasses 1.5 meters (5 ft) in length.

8 Bitey Otters That Grew As Large As Wolves

Around six million years ago, the wetlands and swampy forests of southwest China housed wolf-sized otters that could mess you up spectacularly. The 50-kilogram (110 lb) Siamogale melilutra wasn’t just big, it was a top predator with a surprisingly strong bite.

Typically, jaw sturdiness decreases as otter size increases. But S. melilutra was an evolutionary outlier with jaws that killed and crunched much larger, tougher prey than any existing otter.

Unlike modern otters that feast on plants and small animals, including rodents and crabs, S. melilutra chomped through the thicker shells of large mollusks and turtles and even through bird bones for additional nutriment.^[3]

7 A Dinosaur Equipped With Sails

Amargasaurus was a sauropod (think brontosaurus but smaller) about 9 meters (30 ft) in length and relatively light at just three tons. It lived during the Cretaceous period 130 million years ago and munched on plants.

But unlike other sauropods, it had two rows of spines that ran down its neck and back. The spines are of uncertain purpose, but maybe they were covered in bone and used for self-defense.^[4]

Alternatively (and the cooler option), the spines may be scaffolding for two parallel sails.

These impressive skin flaps could have helped to dissipate heat. Or the sail may have been used for mating displays and then was evolutionarily selected because lady Amargasauruses preferred prominent spines and sails—and you know they all did.

6 Ankylosaurs Survived Thanks To Nasal Air Conditioning Systems

Massive dinosaurs like the heavily horned and armored ankylosaurs countered their higher risk of overheating with convoluted nasal passages that worked as a natural AC.

In addition to smelling things, noses also heat and humidify inhaled air. In birds and mammals like us, a furl of bones and cartilage improves heat exchange by increasing surface area. But for ankylosaurs like the hippo-sized Panoplosaurus and the rhino-sized Euoplocephalus, evolution followed a different route.

CT scanning and fluid dynamics revealed “insanely long nasal passages coiled up in their snouts” which researchers liken to crazy straws. And they helped a lot. Just by playing with nasal passage geometry, evolution found a way to increase the gigantic dinosaurs’ heat-transfer rates by 50 percent.^[5]

5 Pterosaurs May Have Been Feathered

Around 230 million to 66 million years ago, the fearsome flying reptiles known as pterosaurs ruled the skies and terrorized the dinosaurs. And it goes that pterosaurs were covered in fur-like pycnofibers.

But recent research contends that they sported a full spectrum of feathers, according to 160-million-year-old remains uncovered at the Daohugou Formation in Mongolia. The remains are so finely maintained by nature’s serendipity that they apparently preserved detail all the way down to the individual feather.

They also suggest that pterosaurs had four different types of feathers about 80 million years before such things appeared on dinosaurs and birds.^[6]

4 Glyptodon Shells Provided Prehistoric Shelters

The Glyptodon was an ancient armadillo. Like other prehistoric beasts, evolution scaled it up to “holy crap” proportions. This giant antediluvian ‘dillo grew to 3 meters (10 ft) in length and weighed a ton, matching a Volkswagen Beetle.

Like the modern armadillo, it carried dome-like armor made of bony plates. But other than its appearance, it wasn’t too threatening to others because it ate plants in its native South American swamplands. It didn’t even have a weaponized club-tail like its fellow glyptodonts.

The Glyptodon showed up on the evolutionary scene two million years ago and disappeared around 10,000 years ago—probably with a lot of help from human hunters, who sometimes used its discarded shell for temporary shelter.^[7]

3 The Frog That Ate Baby Dinosaurs

Meet Beelzebufo ampinga, the armored devil frog which definitely merited its name.

The pugnacious Beelzebufo lived around 70 million years ago in Madagascar, the land of oddities. And it was disgustingly big. It weighed in at 5 kilograms (10 lb) and measured 41 centimeters (16 in) in length like a bumpy, slimy beach ball.

It had a cranial shield to protect its noggin and insane bite strength which helped it to ambush its prey, as per modern horned frogs. According to researchers, it could have crunched baby dinosaurs with a bite that imparted 2,200 newtons, as much force as a wolf or even a tiger.^[8]

2 Beaked, Turkey-Sized Ornithopods That Swarmed Prehistoric Plains

Some of the most successful dinosaurs of all time—such as the ornithopods—weren’t at all fierce. The ornithopods were bipedal plant grazers that became one of the most successful groups during the Cretaceous period 146 million to 66 million years ago.

Based on scant remains, including a complement of tail bones and a bit of foot found in Australia, researchers pieced together the ornithopods’ Diluvicursor pickeringi. This beaked, turkey-sized animal straddled the edge of the Antarctic Circle 113 million years ago when Antarctica and Australia were still connected.

This dino was built for agile running with a short, muscular tail and stout, powerful legs. But it only terrorized plant life, feasting on mosses, ferns, seeds, lichens, and possibly flowers.^[9]

1 Unicorns Did Exist

Unicorns did exist. But they were horrifying and awesome and probably gored an early human or two with a horn that measured more than 1 meter (3 ft) in length.

It was known as Elasmotherium sibiricum, and records show it split off from modern rhinos about 40 million years ago. At 3.5 tons, it was tanklike and twice the size of extant rhinos, although its anatomy was built running.

Researchers thought that the “Siberian unicorn” died out about 100,000–200,000 years ago. But now they say it didn’t disappear until much more recently—39,000 years ago.

Luckily for us, as climate change delivered Earth from an ice age, it also destroyed the Siberian unicorn’s primary food source of tough, dry grasses and dumped it into the evolutionary reject pile.^[10]

Ivan writes about neat things for the Internet. You can contact him at [email protected].

With thoughts of sugarplums dancing in your head, you may not be worried about what goes bump in the night during these long winter months. However, Santa Claus and Jack Frost aren’t the only characters that come with the cold, dark winter.

Throughout history, several mythical creatures and monsters have scared generations of people who were getting into the Christmas spirit. Winter brings not only cheer and happiness but fright and terror to those who still believe in ancient myths of ice monsters and wicked snow creatures.

While most of us are getting ready for winter with holiday preparations and hand warmers, others are anxiously awaiting the arrival of a wild assortment of monsters. Here is a collection of evil winter creatures you definitely don’t want to run into this holiday season.

10 Yuki-onna

Just because she’s pretty doesn’t mean you should ask her in for a drink. Yuki-onna (“snow woman”) is a myth with apparent sightings documented as far back as the 14th century. The Yuki-onna is said to be an evil being taking the form of a beautiful woman.

With long, dark hair and skin so pale that it appears transparent, she is a beautiful woman at first sight. Many say that she does not even have feet as she glides around during harsh snowstorms and blizzards. She appears to travelers who are lost or stranded in bad weather and kills them with her frigid breath, leaving behind nothing but frost-coated corpses.

Some say that she is able to manifest as a woman holding a baby, enticing well-intentioned strangers to help her and her poor child out of the storm. As soon as a mortal touches her baby, that human being is frozen on the spot. While her beauty is enticing, it is known that she can be identified by her eyes, which strike fear into the heart of any mortal if he is unfortunate enough to gaze into them.^[1]

9 Chenoo

Chenoos also take a humanlike form, and yet they are much more frightening. Of course, this may be because they are human-eating giants. Maybe the most terrifying thing is that they were once mere humans, which essentially makes them really tall, overweight cannibals with a lack of proper hygiene.

Occasionally, an evil spirit will possess a human, turning him into a Chenoo. More often, however, a human is turned into a Chenoo as a result of such a heinous crime that it is believed one cannot remain human after it is committed.^[2]

This crime?

Cannibalism. Yes, almost every Chenoo was once just a man-eating human. Due to this crime, it is said that the heart turns to pure ice, triggering the change from human to monster.

Unlike most other evil creatures, though, a Chenoo can return to its human form. To do this, the heart must either be extracted or thrown up by the Chenoo itself. Then the icy heart must be destroyed by being completely melted. When the Chenoo has its heart replaced by a human heart, it turns back into a human.

The lesson here? Don’t eat other people!

8 Ijiraq

An Inuit shape-shifter, the Ijiraq preys on small children and those with naive hearts. No one knows what an Ijiraq looks like in true form as it is invisible when not shape-shifting into its decided form. As a result, they are very hard to spot.

They can appear as any sentient being they desire, making their tactic similar to guerrilla warfare. It is said that they live in a world between the living and dead. This world cannot be reached by mortals.

If a human were to be near their home, the human is suddenly confused and gets turned around, ensuring their evil stomping grounds are never discovered. However, these beasts can take children with them and then feast on the kids with their shape-shifting friends.

Ijiraqs lure children far away from their villages where these monsters will abandon, hide, or eat the children. If the child is spared as a meal, he still will never be able to find his way home, making his death drawn-out and cruel.^[3]

The only hope for surviving such an encounter is listening closely. When an Ijiraq arrives, a humanlike whistle is heard. Yet there is no source. If you hear this upon meeting someone, it is a good sign to run as it’s probably a shape-shifter looking for its next tasty meal.

7 Nuckelavee

This creature is the centaur from your worst nightmares. A crude depiction of a creature similar to a centaur yet much more sinister is what people typically believe that a nuckelavee looks like. They have two heads with one giant red eye that resembles flames.

Most disturbing, perhaps, is the fact that they have no skin and you can see their black blood coursing through their twisted veins. A demon that roams the snow-laden grounds of Scotland’s uppermost northern isles is confined during the summer months, which only makes it more eager to cause pain and suffering during the winter.

During the summer, the Sea Mither, or spirit of summer, is able to keep these demons at bay because they live underwater then and only emerge when the Sea Mither can no longer control them. It is said that the breath of the nuckelavee is toxic, and just one faint breath can kill even the strongest of men.^[4]

The nuckelavee has been blamed for past famines and droughts within the surrounding villages. The villagers used to say a prayer each time its name was uttered as they were terrified that the nuckelavee would torment them for speaking such taboo.

6 Mahaha

The Mahaha is another Inuit demon that terrorizes the Canadian Arctic. They are extremely gaunt yet muscular, with strength unimaginable. They have ice-blue skin that appears to be stretched so tightly around their bodies that their bones are visibly protruding. The creature’s head hangs low as its large, sullen eyes peer at its victims from behind the stringy hair falling over its face.

The Mahaha is always smiling and giggling as it thoroughly enjoys the torture of its victims and becomes giddy upon having a new one. This monster has inhumanly long fingernails that resemble knives. With these nails, the Mahaha “tickles” its victims to death. This tickling is merely shredding the victim bit by bit.^[5]

The mark of the Mahaha is just as unsettling as the sight of the creature itself. Every last victim of the Mahaha is left with a twisted, evil smile bared as the corpse lay frozen after the attack. The sight of a victim alone was enough to strike fear into the hearts of generations lost long ago.

5 Pal-Rai-Yuk

Yet another Inuit creature, the pal-rai-yuk is purportedly a giant sea monster that resides in the bays of the Alaska Key Islands. This sea creature has a snakelike head that protrudes from the water almost 3 meters (10 ft). Although its upper body resembles a snake, it is said to have thick fur, six legs, three dorsal fins, and two heads. Each head has a long, slimy tongue ready to eat up.

Despite its size, the pal-rai-yuk is known for being able to whisk its human victims right off docks and piers so quickly that no one but the victim even notices. If one is crazy enough to try to set up a playdate with this monster, it is rumored that the creature can also be summoned.

To call the pal-rai-yuk, one must tap on the bottom of a wooden pier. If you’re feeling a little crazy, you can even summon it via the bottom of a wooden kayak. While this monster stays in the water throughout most of the year, it is able to “swim through the earth” with the aid of snow during the winter months.^[6]

4 Kogukhpak

One of the oldest Yupik mythological tales is the story of the Kogukhpak. Over 40,000 years ago, it was believed that mammoth carcasses were actually the corpses of these subterranean monsters. These massive creatures were said to have large tusks like a mammoth. Yet, they had bulbous bodies and legs like frogs.

As the Sun was the only thing that could kill them, they lived underground for most of the year. The winter solstice is the only time that they can emerge from the earth to hunt and ignite the fear of the locals.^[7]

Those mammoth skeletons were rumored to be from the foolish Kogukhpak that stayed out a little too long during their solstice solitude and were evaporated as soon as the smallest bit of sunlight touched their round, bulging bodies.

3 Qiqirn

While some believe it to be a vampire dog or a hellhound, the Qiqirn is typically known as a large, evil, spirit dog. It is very easily distinguished from a regular dog as it is completely bald with the exception of its paws, the tip of its tail, and the area around its mouth.

These spirit dogs approach travelers during the winter months when they are alone at night in unknown lands. When the beasts get close enough to the traveler, he will suffer endless fits until liberated from the pain by death.

While this may seem awful, it is easy to ward off a Qiqirn as they are known for being just as skittish as they are fierce. As long as you can identify the beast, you can escape its wrath. Simply shouting the name of the being sends it running with fear.^[8]

A Qiqirn feeds off the unwitting and feels threatened when its intended victim knows its intentions.

2 Wendigo

Native to the northern forests of the Atlantic coast, wendigos are humanlike, man-eating monsters from Algonquian folklore. Known for its striking height of 5 meters (15 ft), this creature is typically associated with famine and hunger as well as the disappearances of many villagers long ago.

Wendigos have an ash-gray skin tone with inhumanly sullen eyes. Their lips are said to be dried out and always covered in blood. While they have a humanlike torso, they have unnaturally long limbs with razor-sharp claws at each end. Their heads are a human-wolf hybrid with horns above the forehead.

Known as “the spirits of lonely places,” wendigos lure lone victims away from others with an imitation of a human voice. The creatures offer warmth and shelter. Once a human is successfully trapped, the wendigos continue to feast on the victim’s flesh. It is said that the putrid smell of their breath reeks of death and decay.^[9]

These creatures can also possess humans. If a person is too greedy, he could be susceptible to wendigo possession and develop an insatiable craving for human flesh himself.

1 Kallikantzaroi

Ever met someone who tried extremely hard to be the best at something, but he could never seem to achieve his goal?

In the mythical world, that is a kallikantzaros of Greek mythology. No matter how hard they try at being evil, they are just no good at it.

These tiny, gnomelike creatures spend their lives working from home, which just happens to be the center of the Earth. They spend the year hacking down the tree of life, which holds up the Earth, in an attempt to end mankind.

They have one flaw, though. During the 12 days of winter solstice, kallikantzaroi can come to the Earth’s surface, something they cannot resist. While they are not inherently evil, they do wreak havoc on humans’ homes and villages when let out.^[10]

People would ward them off by setting colanders on their doorsteps before nighttime. Kallikantzaroi are known for being incredibly dumb, so much so that they cannot even count to three. It is believed that they will waste away in front of the colander trying to count all the holes until sunrise, when they are forced back into the Earth.

When these annoying creatures finally return to their home, they will find that the tree of life has completely restored itself. They spend the rest of the year trying to hack it down again until they can come to the surface once more.