Ancient giraffes had shorter necks and armored heads - study

New fossils found in northern China have revealed that ancient giraffes had a disk-shaped bone structure on their heads intended for head-butting opponents.

 A giraffe in the Akagera National Park.  (photo credit: ATZMON DAGAN)
A giraffe in the Akagera National Park.
(photo credit: ATZMON DAGAN)

An ancient type of giraffe had a shorter neck and a disk-shaped armor on its head in order to head-butt rivals, a new study has found.

Published in the peer-reviewed journal Science, the study says that the ancient giraffes battled for superiority by head-butting each other.

They also were found to have complex head and neck joints that enabled them to receive rival head-butts without suffering from damage to the spine.

The ancient giraffe fossils were found in northern China and were given the name Discokeryx xiezhi, after a mythical Chinese one-horned creature called Xiezhi that resembled a goat.

Why do giraffes have long necks?

While giraffes' elongated necks were historically a classic example of adaptive evolution enabling them to reach high foliage, they may actually have developed in order to give them a head-butting advantage over their opponents, the study argues. Reaching high leaves may only have been an added benefit.

Newly-born giraffe 'Toy' at the Jerusalem Biblical Zoo (credit: YAARA FOREST TAMARI)
Newly-born giraffe 'Toy' at the Jerusalem Biblical Zoo (credit: YAARA FOREST TAMARI)

The armor was probably made out of a layer of keratin, the same material that rhino horns and human nails are made of.

The fossils were dated to approximately 16.9 million years ago during the early Miocene period. Long-necked giraffes only emerged during the early Pliocene period, some 10 million years later.