Top 10 Most Dangerous Non-Dinosaurs

This list is for carnivores only. Believe me, there are certainly very dangerous non-dinosaur herbivores as well...

10. Dimetrodon

Time- Permian

Size- 10-13 ft long, 400-600+ pounds

Notes- one of the largest land carnivores before the dinosaurs, this famous pelycosaur has a mouth full of sharp teeth and a powerful bite.

9. Cretoxyrhina

Time- Late Cretaceous

Size- 16-20 ft long, 1,000-2,000 pounds

Notes- Cretoxyrhina was about the same size as a modern day great white shark and likely had an attitude problem to match. It's jaws were lined with hundreds of sharp, serrated teeth perfect for slicing flesh.

8. Terror Bird

Time- Paleocene-Pleistocene(depending on species)

Size- 9+ ft tall in the largest species, 300-400 pounds in the largest species

Notes- Terror Birds were apex predators capable of hitting a top speed of over 30 miles per hour. Along with their great speed, these brutes had a wicked beak and huge clawed toes.

7. Basilosaurus

Time- Late Eocene

Size- 40-65 ft long, 15-25 tons

Notes- Though Basilosaurus wasn't as smart as modern whales, it was likely quite intelligent for it's time. Smarts, along with razor sharp teeth, would make this whale a potent killer.

6. Dunkleosteus

Time- Devonian

Size- 20-30 ft long, 2-3 tons

Notes- One of the world's first true super predators, Dunkleosteus had an armored head and powerful jaws. It didn't have teeth, but rather sharpened bones that acted like scissors. 

5. Smilodon

Time- Pleistocene to Holocene

Size- 6-9 ft long, 400-800+ pounds

Notes- Smilodon not only had the typical weapons of a big cat(sharp claws and teeth), but it took one of those weapons to the extreme. The teeth, the biggest of any cat, measured an incredible 11 inches long and would make short work of many prey species.

4. Dire Wolf

Time- Pleistocene

Size- 5-6 ft long, 110-175 pounds

Notes- You may be surprised to see this one so high up. The Dire Wolf, the largest wolf on record, was a truly dangerous predator. It had large canine teeth and a powerful bite and build. But even more dangerous, this intelligent animal(likely smarter than it's rival Smilodon) was a pack hunter. 

3. Sarcosuchus

Time- Early Cretaceous

Size- 33-40 ft long, 5-7.5 tons

Notes- Sarcosuchus, potentially the largest crocodylmorph of all time, is easily one of the most dangerous animals that ever called Africa(and likely South America) home. This armored titan had the goods to take on dinosaurs, including giant killers like Spinosaurus and Carcharodontosaurus.

2. Mosasaurus

Time- Late Cretaceous

Size- 30-50 ft long, 3-8 tons

Notes- Like it's modern day monitor lizard cousins, Mosasaurus was a lethal hunter. Not only was it the biggest predator in it's environment, it also had a double row of jagged teeth lining it's enormous jaws!

1. Megalodon

Time- Miocene-Pliocene

Size- 50-60 ft long, 45-65 tons

Notes- One of the largest carnivores the Earth has ever known, Megalodon possesses some of the most lethal weapons ever seen. Teeth as long as 7 inches lined its enormous jaws and were backed by a ~20 ton bite force, the most powerful of any animal ever save for potentially Tyrannosaurus rex. This giant shark feared nothing and ate everything.

Honorable Mentions

Pliosaurus

Megalania(Varanus priscus)

Inostrancevia

Titanoboa