Buzz
The Earth once teemed with extraordinary creatures. Thousands of years ago, enormous and bizarre animals roamed the land, many so massive they would dwarf a human.
We often hear about the dinosaurs from millions of years ago, but the planet was home to an even more diverse range of creatures than Jurassic Park ever imagined. There were countless strange and remarkable animals, each more fantastical than the last.
10. Livyatan: The Whale That Devoured Its Own Kind
Around twelve million years ago, a species of sperm whale known as Livyatan melvillei thrived off the coast of Peru. They reached a similar size to today's sperm whale, with some individuals growing up to 18.5 meters (60.7 feet) in length. However, the key difference was the size of their mouth, packed with enormous, tear-shaped teeth.
These massive whales hunted other whales, with jaws resembling those of modern killer whales but much larger—three times the size. Some of their razor-sharp teeth measured up to 0.3 meters (1 foot) long and 10 centimeters (4 inches) wide, perfectly adapted for slicing into whale flesh and tearing it apart.
Despite sharing the sea with the gigantic megalodons, the largest sharks to have ever existed, Livyatan melvillei had no natural enemies. Instead, they preyed on enormous baleen whales, making the seas of prehistoric Peru a battleground between the two deadliest predators ever to rule the oceans.
9. Paraceratherium: The Rhino That Weighed Five Times More Than an Elephant
Paraceratherium might have been the largest mammal ever to walk the Earth. This colossal rhinoceros reached lengths of 7.5 meters (25 feet), with its shoulders towering 5.5 meters (18 feet) above the ground. Its long neck allowed it to reach a staggering height of 8 meters (26 feet).
More impressive than its height was its immense weight. The largest individuals weighed up to five times the mass of a modern elephant.
Paraceratherium lacked horns, but its size rendered them unnecessary. It had a set of teeth so massive they’ve been likened to an elephant’s tusks. Additionally, Paraceratherium boasted an enormous tongue that it could use to sweep entire trees clean with a single flick.
Until recently, Paraceratherium was considered the undisputed largest mammal ever to walk the planet—and it may still hold that title. However, it now faces competition. Based on bone fragments, there’s a theory that an ancient Asian elephant known as Palaeoloxodon namadicus may have been even larger. No complete skeletons of these elephants have ever been found, but their thighs alone were almost as large as a full-grown man.
8. Cygnus Falconeri: The Enormous Swan That Coexisted With Tiny Elephants
The island of Malta was once home to some of the most bizarre creatures in the animal kingdom. Hundreds of thousands of years ago, during the Middle Pleistocene era, the island was inhabited by pygmy elephants, which were overshadowed by enormous swans.
These giant swans, known as Cygnus falconeri, were truly massive, with wingspans reaching 3 meters (10 feet). They were so large that they couldn't fly and instead roamed the land, feeding and living there. Surprisingly, these swans were larger than the local elephants, which stood at about 80 centimeters (31 inches) tall—roughly the size of a greyhound dog.
Many artworks of these giant swans depict them harassing and even hunting the tiny elephants. While we’ve found no evidence that the swans actually preyed on the elephants, the vivid image is so captivating that we can’t help but imagine it as true.
7. Platybelodon: The Elephant With Scythe-Like Teeth
The Platybelodon may look a bit unusual, but it was a formidable creature. These ancient elephants boasted incredibly long teeth that functioned like scythes.
This early elephant had a massive, open jaw resembling a giant shovel—and that’s basically what it was used for. Their unusually long lower incisors helped them scoop up dirt to uncover hidden objects. These teeth could also serve as scythes, slicing through dense vegetation.
Any laughter would have quickly faded if you saw one of these animals in action. The Platybelodon would grab thick tree branches with its trunk and hack them off with its massive teeth, like using a machete to chop through wood.
6. Heteromorph Ammonites: The Mollusks With Wild, Twisted Shells
We’re familiar with the round, spiral shells we see today, the shape commonly associated with mollusks and snails. It seems like the only natural form for a shell. However, millions of years ago during the Cretaceous period, shells weren’t always so neatly coiled.
Picture a spiral shell, like a coiled rope, then imagine that rope getting tangled. That’s a close idea of what mollusks known as heteromorph ammonites looked like around 100 million years ago. Their shells were twisted into every imaginable shape.
Many of their shells were chaotic in form. One genus, Nipponites, had shells that resembled tangled balls of string or a pair of headphones squashed into someone's pocket for too long. These bizarre shapes likely made life difficult. In fact, scientists still aren’t sure how these creatures could move around with such awkward shells trailing behind them.
However, some were truly stunning. The ancient mollusk Helioceras possessed a heteromorph ammonite shell shaped like a spiral staircase, rising gracefully into the air.
5. Garganornis - The Enormous Aggressive Goose That Used Its Wings for Combat
In ancient Italy, a giant goose called Garganornis ballmanni roamed the land—and if you’ve ever experienced a goose chase in modern times, you’ll understand why this ancient creature was something to fear.
The Garganornis weighed in at a hefty 23 kilograms (50 lbs) and had enormous wings which it used to strike down other creatures, rather than for flight. Its wings were equipped with sharp, bony protrusions designed specifically for slapping other animals across the face.
Garganornis wasn’t looking for trouble. As a flightless herbivore, it spent most of its time foraging for plants on dry land. However, it wasn’t safe from aerial predators. If a predatory bird tried to swoop down and make a meal of it, the Garganornis would likely respond with a powerful blow from its knuckle-like bony wings, making for a rather tough snack for any would-be attacker.
4. Hoplitomeryx - The Deer with Five Horns
Coexisting with those fierce, angry geese was an animal that could easily belong to any mythology: the Hoplitomeryx, a five-horned deer.
The Hoplitomeryx would have resembled a modern deer in many ways, but it would have been slightly larger with longer legs. Some even liken its appearance to that of a giraffe. However, the most striking feature of this creature would have been its unusual, protruding horns.
In addition to the typical pair of horns found on a modern deer, the Hoplitomeryx sported a second smaller pair that curved outward above its eyes, along with a large central horn extending from the middle of its skull.
Its teeth were equally imposing. Its canines, curving outward like massive swords, were so large that they protruded from the sides of its mouth even when its lips were closed.
These features together created a presence both majestic and terrifying. The horns on its head looked like a crown, and paired with its sharp, jutting teeth, they gave the Hoplitomeryx a look far more intimidating than any deer in a Disney movie.
3. Thylacoleo - The Mammal with the Strongest Jaws on Earth
Without question, one of the most fearsome creatures of the prehistoric world was Thylacoleo, a mammal boasting the world’s most powerful jaws.
These creatures were about half the size of African lions, but their jaws might have been even stronger than the king of the jungle's. Every part of Thylacoleo's skull was built for power, though this meant it had a relatively small brain. But sacrificing brainpower was a small price to pay for such an immensely powerful bite.
Within their mouths, Thylacoleo possessed large, fused teeth that worked like thick, long cleavers, perfect for hacking into flesh. Their claws were just as formidable. They had enormous, curved claws that could retract like a cat's, maintaining a razor-sharp edge. Thylacoleo could rise on its hind legs, using its unusually thick tail for balance like a tripod, freeing its claws to slice through the bellies of its prey.
Most likely, they were ambush predators—and brutal ones at that. They could climb trees, lie in wait, then leap down and attack their giant kangaroo neighbors, tearing them apart and feasting on their insides.
2. Arsinoitherium - The Double-Horned, Elephant-Sized Rhinoceros
The Arsinoitherium would have been an imposing sight to behold up close. Resembling a rhinoceros, this creature had two enormous horns protruding from its nose.
These horns measured about 1 meter (3.3 ft) in length and 0.3 meters (1 ft) in width. A single goring from them could easily split you in two. To make matters worse, Arsinoitherium also had a smaller pair of horns sitting above its eyes.
These animals were more closely related to elephants than rhinos, standing a towering 2 meters (6.6 ft) tall, well above the height of most humans. They were herbivores, not predators, but their readiness to defend themselves was evident if any threat arose.
If you ever managed to anger one, their only disadvantage would be their legs. They had odd, stubby legs that couldn't straighten. So, if one were to give chase, you'd likely have no trouble escaping.
1. Leedsichthys - The Fish Bigger Than A School Bus
The largest fish to ever inhabit the Earth was the Leedsichthys, a colossal creature that once swam through the waters of Europe.
We can only estimate its true size, as a full skeleton of Leedsichthys has never been discovered. However, even the most conservative guesses suggest the creature was about 17 meters (56 ft) long, making it larger than a school bus. Some more extreme theories claim that Leedsichthys may have surpassed even the size of a blue whale.
The “bigger than a school bus” theory seems the most probable, yet that alone makes Leedsichthys the largest fish to ever swim in Earth's oceans. Its enormous size was such that the gill rakers inside its mouth were once mistaken for dinosaur jaws.
Interestingly, dinosaurs were the natural predators of Leedsichthys. Living millions of years ago during the Mesozoic era, it’s thought that dinosaurs would occasionally snack on these giant fish, each about the size of a small house.
