Paraceratherium was a huge, hornless relative of modern rhinoceroses that lived across Asia roughly 34 to 23 million years ago.
An elephant-sized rhino relative
Adults are estimated to have weighed somewhere around 15 to 20 tonnes — comparable to or exceeding a modern elephant — with an extremely long neck and legs suited to browsing high tree foliage, more like a giraffe's feeding style than a rhino's. Standing at the shoulder, it may have reached roughly 5 meters (16 ft) tall, tall enough to reach vegetation well above the heads of most other Ice Age-era herbivores that came long after it.
Why it looked so unusual
Paraceratherium's combination of features — a rhino's basic body plan, an elephant's mass, and a giraffe's proportions — makes it one of the stranger-looking giants of the fossil record, without a close modern equivalent to compare it to directly.
A record among land mammals
While the biggest dinosaurs still dwarf it, Paraceratherium is generally considered among the largest land mammals ever known to have existed, alongside a small number of other extinct giants.