Currently, there are an estimated 8.7-9.0 million species of organisms on earth, and roughly 1 to 2 million of those are animals. However, if you were to include extinct animals, the list would be much longer. Scientists have concluded that around 99 % of all species that ever lived are currently extinct. There are also records such as the red data book that document most species. However, there are more animals with characteristics and features so unique that nothing quite like them exists today.

Anomalocaris

Imagine a cross between a prawn and a scorpion. Now, scale that up to the size of a human, add a few claw-like appendages and a pair of eyes on top of a stalk. This is how someone would describe Anomalocaris if they would have seen it alive.

This ancient prawn was the apex predator of its time roughly  530 million years ago. It was also one of the biggest organisms in its time, usually reaching lengths of over 6 feet. The body structure hinted that Anomalocaris was a very fast swimmer and would pursue its prey through the ancient oceans. Once it was within striking distance of the prey, it probably used its long, spiky appendage to capture and possibly impale its prey. Anomalocaris was related to arthropods like crabs and lobsters and has been even cited as a transitionary animal, from proto-arthropods to arthropods. It died out in the Great Permian Extinction along with 90% of all life on earth.

Smilodon

A lion, tiger or any other big cats are formidable predators, capable of dispatching their prey with ease. Now image a large big cat, such as a lion, but with fangs that are so large that it sticks out of its mouth like giant steak knives.

Smilodon was perhaps one of the fiercest predators of its time, hunting big game such as Mastodons (prehistoric elephants). Its body was robust and stocky, capable of quick sudden bursts of speed. Anatomy suggests that the animal was an ambush hunter, where it would get close enough to its prey before pouncing. The long fangs would slice into its prey’s neck and sever an important artery or vein. The last Smilodon became extinct roughly 10,000 years ago.

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