This is Lisowicia bojani, a newly-discovered dicynodont that lived 237 million years ago, in the Triassic period, when dinosaurs first rose to dominance. But it's not a dinosaur, or even a reptile. It's an early relative of mammals. The popular notion of mammal ancestors is that they were small and hid themselves from carnivorous dinosaurs, and were therefore able to survive the cataclysms that killed off the dinos. The latest specimen of Lisowicia bojani, found in Poland, was the size of an elephant: eight and a half feet tall and 14 feet long.
Indeed, the discovery of the elephantine Lisowicia bojani—a four-legged creature weighing an estimated 9 tons (18,000 pounds)— is rewriting evolutionary history. Dinosaurs, this new research suggests, weren’t the only large animals to romp around the Triassic landscape.
To be clear, dicynodonts were not true mammals. As Niedźwiedzki explained, they’re extinct non-mammalian therapsids—a group of synapsids that includes mammals and their ancestors (synapsids are sometimes referred to as proto-mammals or stem mammals). Dicynodonts are a sister line to the mammalian line, but they’re not our direct ancestors. They’re more like our distant cousins, similar to the way monkeys are distant cousins of humans.
Other dicynodont are known, but they are smaller. The discovery puts a new spin on the line of evolution that led to mammals. Read about Lisowicia bojani at Gizmodo.
(Image credit: Karolina Suchan-Okulska)