The age of dinosaurs was a trying time for survival. Vicious carnivores lived amongst enormous herbivores. The climate was often unforgiving. During the Triassic period, for example, the planet was hot, dry and covered in desert. And there were no polar ice caps to escape the burn.
Earthquakes and volcanic eruptions were a plenty, eventually breaking up the global continental block of Pangea. All the while, theropods tried their best to hold on to their status at the top of the food chain. This resulted in some ever-so-scary beasts.
The Scariest Dinosaurs
Humans should be glad they weren't around when these frightening dinosaurs terrorized the landscape. Here are seven of the scariest dinosaurs the world has ever seen.
1. Tyrannosaurus rex
I would be remiss if "the king of lizards," known as T. rex, did not top the list. With a bite force equal to the weight of three small cars, they had little means of escape when it bared down on its prey. T. rex dominated North America in the late Cretaceous Period, 68-66 million years ago. With teeth the size of bananas and a body size equaled that of a school bus, it weighed in at around 8 tons with a muscular tail and a taste for sauropod blood.
2. Velociraptor
What it lacked in size, it made up for in sheer viciousness. Velociraptor was a turkey-sized predator that lived in the Gobi desert 75 million years ago. But this little guy had a fierce weapon on its second toe: an outsized claw meant for shredding.
Researchers initially thought that the giant claw was used for disemboweling its prey, but now believe it was used for stabbing and slashing them. Either way, you wouldn't want to end up on the other end of a battle. It had razor-sharp teeth that would have been replaced throughout its life so that its fearsome bite was kept in tip-top condition.
Read more: The Real-Life Inspiration Behind the ‘Jurassic Park’ Velociraptors
3. Spinosaurus
If you want to jump back in your seat, take a look at an image of Spinosaurus. This Cretaceous beast was a large carnivore found in Africa. It lived close to the water and likely loved to go for a dip while on the hunt for the marine species it terrorized. It was named for the hard, protruding sail that ran down its back and was also the largest carnivore that's ever been discovered.
4. Allosaurus
This large theropod hunted dinosaurs that only the most vicious beasts would have any chance of bringing down. Allosaurus loved the giant Diplodocus as well as Stegosaurus with its heavy bone plates protecting it from harm.
Fossil evidence has even shown an Allosaurus in a battle with a Stegosaurus. Found in North America and also Portugal in the late Jurassic, it had sharp teeth that were curved backward to keep prey from escaping its bite. While it wasn't as large as T. rex, it was still a formidable hunter with serrated teeth perfectly designed to rip through its prey.
Read More: Dippy the Dinosaur: Understanding the Famed Diplodocus
5. Giganotosaurus
Giganotosaurus was taller than T.rex though its body was slimmer and less bulky. It lived in South America during the Early Cretaceous and likely hunted the enormous Argentinosaurus.
As a result, it's been called the "Giant South Lizard." It likely weighed up to 15 tons but was fast and agile for its size, chasing after prey and then ripping them apart with its serrated teeth. Some evidence suggests that it could run up to 30 mph.
6. Carcharodontosaurus
According to some scientists, it's a large carnivore that was "Africa's answer to T.rex." Uncovered beneath the Saharan sands, Carcharodontosaurus had 6-inch long serrated teeth housed in a giant, narrow skull. Packs of these large carnivores likely hunted huge sauropods that would have otherwise been impossible to bring down.
7. Ankylosaurus
Ankylosaurus is the only plant-eater to make the list, and with good reason. When it felt threatened, its armored tail could deal crippling blows that shattered bones and brought down its predators.
And its whole body was armored against its enemies. Though it wasn't going for meat, getting in the way of Ankylosaurus was never in a dinosaur's best interest. New evidence suggests that its boney tail could incapacitate its predators by breaking the ankles of foes like T.rex.
Read more: Take an In-Depth Look at What Dinosaurs Really Looked Like