Fossils from 16.9 million years ago are from a prehistoric giraffe relative with a much shorter neck than our modern versions. Instead, it has a plated skull likely used to butt heads with rivals, like a bighorn sheep or pachycephalosaurus. Scientists say this adds weight to the idea that the giraffe’s long neck didn’t evolve to eat leaves from tall trees, but rather as a fighting mechanism between males.

Long necks mean that giraffes don’t have as much competition for food. But male dominance behavior is likely the stronger evolutionary force. Modern male giraffes partake in a behavior called necking, where they fight each other by bashing necks. The longer and stronger the neck, the more territory and mates.  

The prestigious peer-reviewed journal Science published the results and the video above. Scientists took CT scans of a skull found in China in 1996 and found similarities to living giraffes and okapis. Its scientific name is Discokeryx xiezhi, which means round-plated horn and references a one-horned Chinese mythical creature. Though we think it looks more like it’s wearing a bowler hat in the artist renderings. It also has thick, overlapping vertebrae. The researchers used computer simulations to demonstrate that this would help the creature use its head as a battering ram.

Artist rendering of prehistoric giraffes head-butting each other
Science Magazine

The analysis also included isotopes in fossilized teeth. This helps determine where an animal lived based on its food and water sources. There are multiple giraffe-like creatures in the fossil record. As you can see in the graphic below, many had odd looking skull adaptations, most likely due to male dominance displays.

Science Magazine

Whether pachycephalosaurus actually used their heads to ram each other is actually still debated among scientists. Their neck shape suggests they were not designed for this and instead may have used their domes to hit each other’s sides instead of skull to skull. Another thing Jurassic World may have to retcon

Melissa is Nerdist’s science & technology staff writer. She also moderates “science of” panels at conventions and co-hosts Star Warsologies, a podcast about science and Star Wars. Follow her on Twitter @melissatruth.