strangest prehistoric creatures to rule the earth

Although pigs, wild boars and warthogs today are known to eat meat on occasion, they are basically vegetarian. On the other hand, the Entelodon, a prehistoric pig relative, was a full time carnivore and possibly one of the most monstrouslooking mammals ever. Standing on all fours, this beast was as tall as a man, and had an immense head armed with powerful jaws and sharp teeth. Scientists believe that it was able to hunt live prey, but that it also scared other predators away from their kills (which should have been very easy). Its bite marks also suggest that it fought viciously with its own kind, and it is even possible that Entelodonts were cannibalistic. Entelodons were quite successful beasts, existing for about 9 million years.

This is by far the smallest creature of the list, but it would still cause hysteria, and perhaps even some heart attacks, if it showed up today. It was very similar to todays scorpions but could grow up to one meter long, perhaps more, and was armed with sharp chelae (claws) and a venomous stinger. Of course, we dont know how toxic its venom was, but considering the considerable amount it injected with each attack, it was most likely a very deadly critter indeed. A predator, Pulmonoscorpius roamed the swampy forests of the Carboniferous in what is today Scotland. Just so you know, during the Carboniferous there were also giant roaches the size of house cats, dragonflies the size of hawks, and centipederelatives up to three meters long. No kidding.

This is a fairly well known prehistoric monster, but it is just so big and scary that it deserves to be in this list. Megalodon (technically called a Carcharocles megalodon) was a gigantic shark, closely related to todays makos and great whites. It could grow up to 20 meters long and weigh up to 60 tons, being almost six times larger than Tyrannosaurus rex! Obviously, the only thing in the sea big enough to feed Megalodon where whales, and indeed, the giant sharks bite marks have been found in the fossil remains of whales all around the world. Although many people like to imagine encounters between Megalodon and TRex, or dinosaurlike marine reptiles, the truth is Megalodon appeared long after the extinction of such creatures, and it wasnt seen alive by any humans either, although it was still roaming the oceans when our australopithecine relatives took their first steps out of the jungle.

Since the formidable Smilodon (better known as sabertoothed tiger) is too well known, we have decided to go for a refreshing change. Enter Xenosmilus, possibly the nastiest feline ever to have existed. The remains of this very large cat (the size of a lion or tiger, but more robust) were recently found in Florida along with the remains of many unlucky giant peccaries (similar to wild pigs) that fell prey to it. Instead of strangling prey or breaking their neck as lions do, or stabbing them as the sabertoothed tiger did, Xenosmilus acted more like a shark or a carnivorous dinosaur, biting off a huge chunk of flesh and causing massive blood loss and shock in a matter of seconds. Compared to modern day felids, a Xenosmilus kill would probably be extremely bloody; so much in fact that it would probably not be shown in Animal Planet! Since we dont know when exactly Xenosmilus became extinct, we cant tell if humans ever met this cat, or fell prey to it.