12 Bizarre Animals That Used to Exist (And How They Went Extinct)
Discover 12 of the strangest creatures that once roamed the Earth, from buzzsaw-jawed sharks to giant, frog-like dinosaur hunters, and learn how they vanished into extinction.
- Alyana Aguja
- 4 min read
Earth’s history hosted some weird creatures, with sharks sporting spiral jaws, monstrous armored armadillos, and dinosaur-swallowing frog-monsters. Every one of them was alive once and lived for their time to meet their extinction in the forms of climate changes, fierce rivals, or their interactions with people. Discover some of the best-kept tales of these creatures gone extinct.
1. Helicoprion – The Buzzsaw Jaw Shark
Image from Wikipedia
The ancient shark Helicoprion, which lived approximately 290 million years ago, had a spiral of teeth that looked like a buzzsaw, referred to as a tooth whorl. Researchers think this whorl helped it cut through soft-bodied animals such as squid. Helicoprion became extinct, probably because of extreme climate shifts that destroyed its ocean environment and food supply.
2. Hallucigenia – The Walking Nightmare
Image from Wikipedia
Around 500 million years ago, Hallucigenia scurried over Cambrian ocean floors on spindly legs with spikes running down its back as protection. Scientists were baffled by its peculiar, otherworldly appearance for decades, questioning which end was up. It probably went extinct as more powerful predators developed and competed with it for survival.
3. Quagga – The Half-Zebra, Half-Horse
Image from Speciologie
A native of South Africa, the quagga resembled a zebra from the front and a simple brown horse at the rear. European colonists hunted it intensely in the 19th century for food and hide, and competition from livestock accelerated its extinction. The last quagga perished in a zoo in 1883.
4. Steller’s Sea Cow–The Gentle Giant of the Arctic
Image from OneKindPlanet
This giant, slow-moving cousin of the manatee reached lengths of 30 feet and inhabited the cold seas close to the Bering Sea. Found in 1741, it was hunted relentlessly for its blubber and meat. It was hunted to extinction within 27 years of its discovery.
5. Megalodon – The Monster Shark
Image from Natural History Museum
This giant predator, which measured as long as 60 feet, dominated the seas some 2.3 to 3.6 million years ago. It hunted whales and other huge sea creatures. The shifting sea temperatures, reduction in food, and competition with other smaller but faster predators, such as great white sharks, led to its demise.
6. Thylacine – The Tasmanian Tiger
Image from Ty Wiki - Fandom
A tiger-striped, kangaroo-pouched marsupial predator, the thylacine inhabited Australia and Tasmania. It was officially declared extinct in 1936 when it was hunted out, killed off by disease, and lost habitat wiped out its population. The last thylacine ever lived in 1936 and died in captivity.
7. Dunkleosteus – The Armored Sea Monster
Image from FictionRulezForever Wiki - Fandom
Dunkleosteus, which existed around 358–382 million years ago, was a terror of a fish with armor plating made of bone and jawbones that could crush nearly anything. It was a top predator until it became extinct due to environmental shifts and competition from smaller, more flexible fish. Its extinction brought an end to the placoderm dynasty.
8. Glyptodon – The Armadillo the Size of a Car
Image from Wikipedia
This extinct giant resembled an armadillo-tank hybrid, featuring a huge, domed shell. Strolling around South America, it probably became the victim of early man’s overhunting about 10,000 years ago. Climate change bringing about a decline in food resources could also have caused the demise.
9. Moeritherium – The Hippo-Elephant Ancestor
Image from Walking With Wikis - Fandom
Neither exactly an elephant nor a hippo, Moeritherium waddled around swamps around 37 million years ago. It had a pig-like body, tiny tusks, and a snout with a trunk-like appearance. Drying up of its swampy environments due to changing climates probably made it extinct.
10. Terror Birds (Phorusrhacidae) – The Flightless Predators
Image from New Hampshire PBS
Up to 10 feet tall, these flightless birds with massive hooked beaks roamed South American landscapes for millions of years. They were swift, lethal hunters that could kill large prey. Some 2 million years ago, their extinction is attributed to competition from developing mammalian carnivores and human intervention.
11. Deinotherium – The Upside-Down Tusk Elephant
Image from FossilGuy.com
This extinct relative of modern elephants sported downward-curving tusks from its lower jaw, perhaps for stripping bark or digging. It inhabited Europe, Asia, and Africa until about one million years ago. Climate change and habitat contraction probably caused its demise.
12. Beelzebufo – The Devil Frog
Image from Dinopedia - Fandom
This enormous prehistoric frog, the size of a beach ball, existed around 70 million years ago in Madagascar. It was strong enough to consume small dinosaurs and had a bite force greater than that of any contemporary frog. Its extinction is probably connected with shifting ecosystems and the introduction of new predators.