5 Terrifying Prehistoric Versions of Modern Animals

5 Terrifying Prehistoric Versions of Modern Animals

Damn, Nature, You Scary!

1. Megatherium


Photo Credit: LadyofHats via Wiki Commons

Nowadays, if you’re thinking of dangerous, deadly creatures, one of the last things that come to mind is a sloth. It’s somewhere near the back, between a baby hippo and a stuffed teddy bear. However, that would not be the case with the modern sloth’s great-great-grandpa, the Megatherium. The term “elephant-sized” is often used to describe it and it is pretty accurate –Megatherium was about the size of a modern elephant. Unlike an elephant, though, Megatherium had giant claws (thought to have been used for digging) and was capable of standing on its hind legs to appear even more massive and get to those hard-to-reach places.


We have a pretty good idea of what Megatherium looked like because we found plenty of fossils all over America suggesting that this species was quite widespread. However, other than that, we have little information on it. We’re not even sure if it was an herbivore or an omnivore. And if you’re thinking that this massive beast lived millions and millions before humans came along, think again. The species appeared sometime during the late Pliocene (about 2–2.5 million years ago) and died out as recent as 10,000 years ago.

2. Paraceratherium


Photo Credit: Diagram Lajard via Wiki Commons

Paraceratherium was an ancient species of rhino and it’s up to you to decide whether it was scarier than its modern contemporary or not. On one hand, it was hornless so it didn’t have the most intimidating element of the modern rhinoceros. On the other hand, it was the largest terrestrial mammal ever! It was about 26 feet tall and weighed around 44,000 lbs but words don’t really do it justice when it’s much better to actually compare it with some modern rhinos (and throw in a human for fun, as well).

Paraceratherium size comparison

Photo Credit: DagdaMor via Wiki Commons

It lived for about 10 million years during the Oligocene period and went extinct approximately 23 million years ago. Obviously, due to its size, it didn’t have a lot of predators but it wasn’t particularly aggressive, either. It was an herbivore and led a lifestyle similar to modern giraffes, using its height advantage to feed on leaves in tall trees.

3. Phorusrhacidae


Photo Credit: Amanda via Wiki Commons

Modern flightless birds are a mixed bag when it comes to danger. We might think that they are all harmless and some of them, like the penguin or the kakapo, are quite harmless (and hilarious – check the Bonus at the end of the article). Others, however, like the ostrich or the cassowary, might look innocent, but they can be quite dangerous. They have very sharp claws and strong feet and they are quite adept at disemboweling. Underestimate them and you might get a mild case of death. And even so, they are nothing compared to Phorusrhacidae.


Photo Credit: Snowmanradio via Wiki Commons

That name is way too hard to remember so let’s just refer to them by their colloquial name – terror birds. These guys were anywhere between 3 and 10 feet tall, depending on the species, and were completely carnivorous. Terror birds lived throughout South America during the Paleocene until the early Pleistocene. That’s between 62 and 2.5 million years ago and, during that time, they were the apex predators in the region. That’s impressive, especially when you consider that their extant relative isn’t the ostrich or the cassowary or any other kind of dangerous bird, but rather the 30-inch seriema.

4. Megalania

Megalania skeleton

We can all agree that komodo dragons are pretty scary, dangerous animals. And yet, they are nothing but a toy version of Megalania, the largest terrestrial lizard in history. Unfortunately, the small number of fossils found means that we have very little information on it. We know that it disappeared roughly 40,000 to 30,000 years ago but we aren’t sure exactly how long it was around for. We’re not even sure about its size. Experts have placed it anywhere from 15 to 26 feet in length, weighing up to 730 lbs. Even at the small range, Megalania still dwarfs the Komodo dragon, the largest lizard we have today. Oddly enough, Megalania is the only animal on this list which is of some interest to cryptozoologists. It might not be as mainstream as Big Foot or the chupacabra, but sights of giant lizards way too big to be dragons have been reported.


Photo Credit: Conty via Wiki Commons

5. Titanoboa


Photo Credit: Ryan Somma via Wiki Commons

Remember that giant snake in the movie Anaconda? In modern times, such animals are nothing but monsters in bad horror movies, but there was a time when these creatures actually roamed the earth. Enter Titanoboa, the largest snake ever (and definitely the animal with the coolest name on the list). At over 40 feet in length and about 2,500 lbs in size, Titanoboa was about twice as big as any snake living today. It appeared roughly 60 million years ago, after the extinction of the dinosaurs which allowed for other species of animals to reach the top of the food chain.

Unsurprisingly, Titanoboa was not venomous, but rather a constrictor. It killed its prey by squeezing it really, really hard. And by that I mean with a force of 400 lbs/sq in. So, obviously, the Smithsonian had to figure out who would win between a Titanoboa and a T-Rex.

Titanoboa robot

And a robot titanoboa because why not? Photo Credit: FutureAtlas via Flickr


Bonus Fact: It’s completely unrelated, but in case you’ve never seen a stubby, awkward flightless bird trying to shag the head of a person, it’s quite amusing.