We should probably be thanking our lucky stars. You see, most of the animals we have to live around are docile, adorable and snuggly creatures, but that wasn’t always the case. Before the appearance of man, the world was once a breeding ground for terror and monsters.
Millipedes are freaky enough at their current size, so we can’t imagine what the world must have been like with gigantic versions of them. This Carboniferous lifeform could grow up to 7 1/2 feet or roughly 2.3 meters long, completely dwarfing the African giant millipede of today, which only grows up to 15 inches or about 38 centimeters. The extinct species of multi-legged critter lived in what is now northeastern North America and Scotland, surviving partially due to a lack of terrestrial predators. As the rainforest climates started to get dryer, this herbivorous arthropod eventually died out.
Serving as the subject of many SyFy movies, the Megalodon lived anywhere from 23 until about 2.6 million years ago. Sharing similar appearances to the Great White Shark, the Megalodon could grow up to 60-feet or roughly 18-meters, which is twice as large as the largest confirmed modern ancestor, and sported chompers that reached lengths of around 7 inches or about 17 centimeters. When hunting whales of approximately the same size, the megalodon was thought to employ a tactic of immobilizing its prey by tearing off means of mobility. During the Cenozoic Era, this massive gliding giant called the Pacific Ocean its home, with fossils being found in areas including the Mariana Trench. Similar to fabled cryptids like Loch Ness, there are many that believe the Megalodon could still roam the depths of the oceans.
There’s something unsettling about oversized, flightless, land-bound, carnivorous birds – which may explain how the Phorusrhacidae earned its nickname, the “Terror Bird.” Reaching heights of up to 10 feet or about 3 meters, the Terror Bird lived during the Cenozoic era and existed as one of South America’s apex predators. The large-beaked prehistoric species used a combination of its powerful beak, strong neck, and claws to tear apart the flesh of its prey and crush bones.
The Titanoboa is the textbook definition for Ophidiophobia. Google “Why are people afraid of snakes,” and, bam! Your search will yield pictures of this 48-foot or 14-meter slithering colossus. In the coal mines of Cerrejon in La Guajira, Colombia in 2009, a series of fossils were found, leading to the eventual discovery of this apex predator of the Paleocene era. Physically similar to the modern boa, the Titanoboa actually shared qualities with the water-dwelling anaconda, such as its affinity for swamps and some of its bone structure. Like many snakes, this large prehistoric variant likely killed its prey by holding it steady with rows of recurved teeth and then crushing it to death.
Like feathered dragons, the Quetzalcoatlus, named after the serpent-god Quetzalcoatl, a member of the Pterosauria order and Azhdarchidae family from the Late Cretaceous Period, towered over the land, stalking and picking off prey with an elongated, spear-like beak. The massive, bird-like terrestrial creature is distinguished by an elongated neck measuring approximately 2-feet or roughly 60-centimeters and a wingspan of up to 52-feet or about 16-meters. Despite a large wingspan, the Quetzalcoatlus was believed to be a quadrupedal and terrestrial being, capable of only short bursts of flight while hunting.
If you think scorpions are scary now, consider one that was just over 2-feet or roughly 60-centimeters long and still packed a venomous punch. The Pulmonoscorpius of the Carboniferous Period was said to have grown to its larger size due to the higher content of oxygen in the air, allowing it to possibly hunt smaller amphibians and reptiles. While research into its diet has been inconclusive, the many similarities it shares with common scorpions point towards a carnivorous appetite. The early arachnids smaller pincers may not look threatening, especially considering its overall size, but if it follows what entomologists know about scorpions, the smaller pincers, and bulkier tales typically indicate a more potent venom.
There’s nothing too scary about the Cretaceous beast that was one part tyrannosaurus, one part crocodile, and all parts teeth and claws. At least, that’s what we tell ourselves to avoid cowering at the sight of this 100-million-year-old monstrosity. According to fossil evidence, the Spinosaurus was the first dinosaur that was able to swim and shared similar bone structure to penguins, similar short hind legs like early whales, and an elongated snout perfect for catching fish. Making this finned creature even more terrifying was its size. Dwarfing the Gigantosaurus by about 10-feet or roughly 3-meters, the Spinosaurus, in all its toothy glory, was the largest known carnivorous dinosaur to have ever roamed the Earth.
Imagine a giant, reptilian mammal about the size of a bear, sporting 5-inch or 13-centimeter long teeth stomping around your neighborhood. That’s what it was like during the Late Permian Period when the Inostrancevia was still alive. As if the teeth didn’t give it away, the Inostrancevia was a vicious carnivore and was the largest member of the Gorgonopsidae family. Don’t let their slender bodies, slightly larger head, and stubby legs fool you. This stem-mammal, or mammal-like reptile, was believed to be fast moving to keep up with its quicker prey.
Ah, so you’re asking what’s so terrifying about this extinct prehistoric ocean-dweller from the Late Devonian period? Let’s start off with the fact that it was an underwater gliding monster that could reach lengths of up to.. well, nobody knows, but the best guess is around 10 meters or roughly 33 feet. Now, let’s focus on the real issue at hand. These things! <Zoom in on image of Dunkleosteus teeth> Do you see these chompers?! The Dunkleosteus was an oceanic predator that would put even the Great White Shark to shame. It was at the top of the food chain for its time, ruling the waters around North America and Europe thanks to bony plates that served as protection, was a means of cutting through its prey, and assisted with its powerful bite force.
There’s nothing scary about pigs. That is, of course, until you equip them with the diet of an omnivore and blow them up to 4-feet or about 1.35-meters tall! The Entelodon is a nightmare pig, though it is actually believed to be more closely related to hippos and whales than to swine. During the Paleogene Period, the Entelodon inhabited much of Europe and Asia, its sheer numbers indicating that it didn’t have a large range of predators. In fact, it’s believed that the Entelodon could easily adapt to changing food sources, making it easy for them to migrate, and was also known for driving off predators from their kill to snag a meal of its own.