A-z - Animals

10 Craziest Prehistoric Sharks!

Keep reading to watch this amazing video

key point

  • Eleven species of sharks have become extinct due to climate change and overfishing.
  • There are 1,000 species of sharks and rays. New species are discovered every year.
  • Modern sharks weigh up to 11 tons.

Sharks have existed for more than 400 million years, during which time thousands of species became extinct. Sharks are pretty crazy today. Consider that whale sharks can reach lengths of up to 60 feet, yet survive almost entirely on tiny plankton! Or check out the hammerhead shark, which has a 360-degree view thanks to its unique head shape!

However, prehistoric sharks had even crazier adaptations. In the following article, we'll take an in-depth look at 10 crazy prehistoric shark species. From anvil heads to "chainsaw mouths," you'll find some amazing prehistoric sharks!

10. Bowfish

extinct shark
Hybodus lived over 200 million years!

©Herschel Hoffmeyer/Shutterstock.com

Hybodus lived approximately 303.4 million to 66 million years ago, making it likely one of the longest-lived prehistoric sharks ever lived. It is definitely the longest-lived on this list! Hybodus looked very similar to modern sharks, and the same cannot be said for the other sharks here, although it does have large spikes protruding from its dorsal fin. These spikes are likely the shark's way of fending off potential predators.

Hybodus sharks have lived around the world for a long time. Today, fossils are everywhere – and all from different times!

One of Hybodus' more interesting features has to do with its teeth. Hybodus' teeth are arranged in two rows in the mouth: the front teeth, then the back teeth. The front teeth help in catching prey, while the back teeth are rounder and help in crushing things like shells!

Because of this interesting tooth structure, it doesn't look like any prey will be able to successfully shake off the crossbowfish. In addition to preying on the larger creatures of the Hybodus' seas, this shark is a major predator in the sea!

9. Cretoxyrhina

Great white shark behind kayak
Ginsu sharks were bigger than modern great whites at 26 feet long!

© karelnoppe/Shutterstock.com

Cretoxyrhina lived during the geological period of the Cretaceous period, when the oceans were populated by many large creatures, all vying for supremacy. While the Cretoxyrhina was not the largest creature in the sea during this time, it was certainly a top predator in many areas. Some fossils show that Cretoxyrhina wasn't even afraid to take on bigger predators!

Read more  Florida Red-bellied Black Snake: What Is It and Is It Venomous?

Cretoxyrhina lived between about 100 million and 75 million years ago – which means it's pretty much the youngest shark listed here! It is also often called the Ginsu shark, named after the Ginsu knife because of its extremely sharp teeth. With around 490 in total, Cretoxyrhina's teeth were so sharp they are thought to be able to slice through meat and even bone with ease.

While one might think that the Cretoxyrhina had plenty of predators due to the crazy times it lived in, in reality, the Cretoxyrhina had plenty of prey . Even Archelon, the largest turtle in Earth's history, was prey for Cretoxyrhina!

8. Sea buckthorn

Extinct Shark - Stethacanthus
Stethancanthus is known as the "Anvil Shark" and it's easy to see why!

©Zero Smany/Shutterstock.com

Stethacanthus lived about 360-340 million years ago, making it one of the oldest sharks on this list! Commonly known as the anvil shark, Stethacanthus had an odd dorsal fin for which it is now known.

We all know what the fins on the upper back of modern sharks look like. The dorsal fin of Stethacanthus was in the same place, but it was not as pointed as in modern sharks. Instead, it has a flat top that looks like an anvil. At the top of this flat fin are enlarged serrations, which experts have long tried to explain.

While many theories suggest why this dorsal fin was shaped the way it is, the most common theory is that the fin was involved in mating between Stethacanthus, as only males seem to have an anvil.

Aside from this crazy feature, Stethacanthus didn't grow very large, and was often much smaller than the average human today. This shark also looks a lot like a porshark!

7. Edstors

Extinct Shark - Edestus
Edestus could grow to be as big as today's great white sharks!

©Michael Rosskothen/Shutterstock.com

Edestus, which lived about 300 to 320 million years ago, was another prehistoric shark that looked… weird . Also known as the scissor-tooth shark, Edestus had curved jaws that caused its teeth to protrude at odd angles. Despite its insane looks, it's a massive 22-foot shark (about the same size as the largest great white shark today)!

The most interesting thing about Edestus is the way it hunted in the past. Sharks have interesting hunting methods, although we sometimes know very little about how prehistoric sharks hunted their prey. The same cannot be said for Edstors!

While it is true that some parts of their hunt remain a mystery, it is thought that Edestus would bob its head up and down and inflict wounds on its prey, something not seen with sharks today!

6. Xenacanthus

Extinct Shark - Xenacanthus
Xenacanthus is known as "The Eel Shark!"

©Warpaint/Shutterstock.com

Xenacanthus, commonly known as the eel shark, went extinct about 202 million years ago, making it another very ancient shark on this list. Although it is a shark, Xenacanthus is definitely not a shark. Plus, this shark is a freshwater shark!

Read more  Standard Dachshund vs. Miniature Dachshund: 5 Differences

Since this shark was a freshwater shark, Xenacanthus likely thrived in waters like swamps, where its eel-like body beneficially helped it navigate around. Larger, more modern sharks certainly would not have thrived in these types of freshwater.

Xenacanthus did not grow too large and is mainly thought to be only a meter long. The shark also looked a lot like a modern eel, hence the name.

The most interesting thing about this shark is its spine. Xenacanthus has a sharp spine that may contain venom, making the shark behave almost like a stingray can! Therefore, this spine is thought to be the main form of protection against predators that are usually much larger than Xenacanthus.

5. Pterodactyl

Prehistoric Shark - Ptychodus
Comparison of minimum (top) and maximum (bottom) size estimates for Ptychodus. Image via PLOS ONE.

Ptychodus was one of the largest prehistoric sharks, estimated at up to 33 feet in length! Like today's whale sharks, it had a mouth full of teeth for crushing food. In contrast, Ptychodus had larger molars to crush large shellfish, rather than the plankton and krill that whale sharks eat today. Ptychodus became extinct about 85 million years ago.

4. Twigfish

Extinct Shark - Cladoselache
Twig sharks lived 380 million years ago!

© Catmando/Shutterstock.com

Cladoselache created the first true shark, living more than 380 million years ago. Though considered a shark, Cladoselache had more in common with common fish than with common sharks today. Cladoselache is much smaller and less muscular than a shark, with a longer and slimmer body that more resembles a larger fish.

The body of the Cladoselache also lacks scales or armor plates of any kind, which is another very interesting appearance feature. During this period, the stick shark was not a major predator in the ocean, probably because of its very fragile appearance. However, these sharks do manage to get away from top predators by swimming so fast!

Cladoselache, although very different from today's sharks, was very important to the evolution of the shark as a whole. Plus, the presence of these sharks is hilarious – and weird!

3. Spiral tooth

Prehistoric Shark - Helicoprion
The Helicoprion is called the "Buzzsaw Shark" for a good reason!

©Grisha Bruev/Shutterstock.com

Helicoprion, also known as the "bubble saw shark," lived about 290 million to 250 million years ago. This prehistoric shark also happens to be one of the funniest new additions to this list. When the first Helicopteron fossils were found, archaeologists didn't know what they were looking at and initially thought they had found an ammonite.

In the end, it was discovered that this strange spiral pattern turned out to be a tooth . Helicoprion had a curled-toothed mandible that protruded from the lower half of the jaw. Helicoprison is thought to be the first shark to regrow teeth after losing them – something modern sharks must do to survive – thus making this shark a good example of shark evolution.

Read more  9 Cute Teacup Dog Breeds

Spiral sharks are scary sharks, especially since no shark before them could regrow their own teeth. These sharks also survived for about 40 million years and survived the Permian mass extinction which killed 90-95% of all living things on Earth and is considered the worst mass mass extinction in the entire history of the planet Extinction!

2. Bluntnose sixgill shark

Largest shark: Blunt-nosed sixgills
The sixgill shark (Hexanchus griseus) was spotted on the first dive of the Mariana Islands Deepwater Expedition while exploring the Santa Rosa Reef south of Guam.

© NOAA Ocean Explorer from the United States – License

There's something different on this list, a shark that isn't even extinct yet! The bluntnose sixgill shark's lineage dates back to the Jurassic era when dinosaurs roamed the Earth. This type of shark can grow up to 20 feet long, about the same length as a great white, but is rarely seen due to its deep water habitat.

Megalodon vs. Mosasaurus - Megalodon
Megalodon can grow to an estimated size of over 50 feet

©Herschel Hoffmeyer/Shutterstock.com

1. Megalodon

No list of prehistoric sharks would be complete without including the Megalodon. Considered the largest fish and shark that ever lived, megalodons were gigantic prehistoric sharks that were top predators in their time. These giants lived between 23 million and 2.6 million years ago and ate big fish — like whales and other large sharks — as if that wasn't a problem.

Megalodons are probably the most famous creatures on this list because they are so fascinating. The only fossils we have to know about these sharks are their teeth – which tend to be three times larger than those of the average modern white shark.

Using their fossilized teeth, experts were able to determine the size of the giant shark. These sharks thrived around the world while alive, as their teeth have been found on every continent except Antarctica.

Megalodons were top predators in their time. Even their former opponents are not as good as them. However, climate change brought colder weather and water temperatures that slowly led to the extinction of the megalodon as they only thrive in warmer water. Plus, it's thought they lost a lot of prey in this change as well. However, the Megalodon is still considered one of the most interesting prehistoric sharks – if not the funniest !

Here's a Roundup of 10 Prehistoric Sharks

  1. Megalodon
  2. Bluntnose sixgill shark
  3. Spiral tooth
  4. twig fish
  5. Leaffish
  6. Xenacanthus
  7. edstors
  8. Acanthopanax
  9. White wax rhino
  10. Bowfish

next…

  • 10 Unbelievable Shark Facts. If you love sharks as much as we do, you'll love these fun facts.
  • Hammerhead Shark vs Great White Shark. Let's compare two species of sharks alive today.
  • Top 10 largest sharks in the world. These sharks are really big!

Next:

  • Saw an alligator biting an electric eel with 860 volts
  • The 15 Deepest Lakes in America
  • Watch rare coyotes and bobcats now