What do the "Star Wars" franchise and prehistoric, giraffe-like creatures have in common? A newly discovered fossil of a fanged, three-horned herbivore that roamed the central Cuenca province of Spain 15 million years ago has been named Xenokeryx amidalae, essentially meaning “strange horn of Amidala.” Its particularly unusual head ornamentation, according to the authors of the PLOS ONE study, resembles the headdress of a fictional monarch in the veritable film series.
One adult and two juvenile fossils were found in remarkable condition, allowing the researchers to reconstruct a relatively complete picture of these animals and the ancient environment they lived in. Paleontologist Israel Sanchez of the National Museum of Natural History in Madrid and lead author of the study, said to Reuters that the shape of the male’s horn was “extremely similar to one of the hairstyles that Amidala shows off in 'Star Wars' Episode 1 when she is the queen of her home planet Naboo.”
Roughly the size of a modern deer, X. amidalae lived in a warm, grassland environment during the Miocene period (23 to 5.3 million years ago), alongside elephant ancestors, ancient horses and crocodiles, along with so-called “bear-dogs,” another extinct group of large, fearsome predators. The males possessed a triple-horned head, with the central horn fanning out into a symmetrical T-shaped ornament. Curiously, although it was a herbivore, the males also featured saber-like fangs. The females had neither, and looked decidedly less unusual.
The horns were likely used for butting purposes, much in the same way modern, male antelopes use their horns for combat in ritualistic mating displays. Although sharp, prominent canines are usually associated with carnivorous eating habits, paleontologists hypothesize that these teeth were also used for combat associated with mate selection.
Image credit: The central horned appendages of X. amidale. Sanchez et al./PLOS ONE
In order to shed some light on its evolutionary lineage, a series of analyses comparing its physical characteristics to similar species were conducted. The features it has that are also found in both closely related species and their presumed common ancestor – physical traits known as synapomorphies – were listed, and computer programs were used to calculate its most likely position on the evolutionary tree.
This bizarre animal belonged to the Palaeomerycidae, an extinct family of ruminants, mammals with specialized stomachs that ferment food prior to digestion, much like the ones used by contemporary cows. This family lived for 50 million years, was widely dispersed across the globe, and all member species possessed one forked appendage on their heads; they are likely to be the ancestors of modern deer.
X. amidalae itself is most closely related to modern giraffes and the okapi, a giraffe-like creature resembling a zebra, both of which are found in Africa. The detail preserved by this collection of fossils was so exquisite that the researchers could confidently say where the entire Palaeomerycidae family fits in the larger group of ruminants.
“It is strange, it posed a good [evolutionary history] problem, it is fun to reconstruct and it is a window to the marvels of the past,” Sanchez noted. “In this case, being a life-long 'Star Wars' fan, it was great to mix my two passions.”