The Earth is some 4.5 billion years old, which is a long time for the untold numbers of creatures it has housed to evolved over time. These five odd-looking species are some of the strangest, long-extinct animals that have been studied. You won't believe they ever roamed our planet.
Elephants are already pretty strange animals. They’re huge mammals that walk on tree trunk-like legs (that they can also hear with) and have giant flexible hoses for noses. However, there used to be an even weirder, elephant-like species walking the Earth. The platybelodon of 10-20 million years ago had a spork-scythe trunk — it would eat by biting a branch and using its second pair of flat tusks at the front of its mouth to cut through vegetation. This is somehow even stranger than (and not nearly as adorable as) an animal snorting water up its nose and then spraying it into its mouth.
Everyone talks about apex predators such as the T. Rex and velociraptor, but no one seems as enraptured by terror birds — a species that was once at the top of the food chain. They were enormous, bird-like creatures that would stab or bludgeon their prey to death with their sharp beak and reinforced skulls. They'd even often kick their prey until they died. Terror birds — a catch-all term for 17 different species of the enormous predators — were largely present in South America during the Tertiary Period (about 2.5 million years ago).
Sometimes it seems like the old "walks like a duck, quacks like a duck" saying only works metaphorically since it doesn't really apply to the genetics of species. A great example of this is the arsinoitherium, a 2,000-pound prehistoric mammal that looks like a two-horned rhinoceros with horns side by side instead of one in front of the other. However, rather than being related to the modern rhinoceros, arsinoitherium’s genetics most closely resemble the elephant and the sea cow. It lived around 30 million years ago in the area around Egypt.
A woolly rhinoceros sounds like a creature invented from the lackluster imagination of a fantasy writer, but these mammals lived in northern Europe and Asia during the most recent Ice Age, meaning they overlapped with humans for roughly 10,000 years. They were depicted in cave paintings that are surprisingly detailed and accurate. The woolly rhinoceros was larger than its modern-day counterpart and was covered in a thick layer of hair — similar to woolly mammoths, which they lived alongside.
This odd little sea creature existed roughly 500 million years ago and its specimens have largely been found in the Burgess Shale of British Columbia, Canada. The opabinia traveled by waving its paddle-esque tentacles up and down; it had five protruding eyes and a proboscis mouth. This creepy little arthropod rarely grew beyond two and a half inches long, and if you think this thing looks absurd, you're not alone. Apparently when the animal was described during a paleontology meeting in the mid-'70s, the room erupted in laughter.