Giraffes are weird animals—there’s the long neck, the fetching eyelashes, strange knobbed horns, long legs and unique cobblestone-patterned hide. It’s hard to imagine the evolutionary pressures that produced such a strange creature, though luminaries including Lamarck and Darwin had some thoughts. Now, the discovery of rare, nearly-complete fossil of a giraffe ancestor may provide new insight into how the skyscraper of the savannah came to be, reports Karen Weintraub at The New York Times.
Described in a journal article in PLOS One, paleontologists uncovered the almost complete remains of an unknown giraffid species at Cerro de los Batallones near the city of Madrid, Spain, along with incomplete skeletons of three other individuals form the species. Weintraub reports that the specimen, named Decennatherium rex by the researchers, is around nine million years old and has four short horns-like protrusions, or ossicones, on its head—one pair curves forward and a longer pair sweeps backward. Modern giraffes only have two ossicones.
Its silhouette is also quite different, with the nine-foot tall creature resembling a moose with a long neck or an okapi, the other member of the giraffid family that's alive today.
Researchers have discovered over 30 extinct ancestors of the giraffe over the years, but none of their skulls survived well enough to shed much light on relationship between the giraffids, according to a press release. This new specimen, which includes a skull, is allowing researchers to build the giraffid family tree by studying the anatomy and morphology of the creatures.
“It’s something most paleontologists dream of and very rarely find,” Ari Grossman, an anatomist at Midwestern University in Glendale, Arizona, not involved in the study tells Weintraub. “The discovery in and of itself was breathtaking.”
The fossils have much to say about ancient giraffes. For instance, the fact that these animals were found in Spain suggests that giraffids ranged well into Europe. The bones also show that there were differences between the males and females of the species.
Most importantly, as Jake Buehler at Gizmodo reports, the fossils have helped researchers sort out the confusing giraffid lineage. The new Decennatherium species represents the earliest-known member of a group of four-horned giraffids known as sivatheres which, along with another branch known as samotheres, ruled Africa and Asia for millions of years. The last members of that group only went extinct during the last Ice Age. The findings show that this sivatheres-samotheres branch of giraffes is millions of years older than previously thought.
The study also indicates that our remaining giraffids, the giraffe and the okapi, are actually pretty far apart in evolutionary terms reports Weintraub. “We’re preserving relics of two very distinct groups of giraffes that were morphologically very different,” Grossman says.
It’s believed that the giraffids first appeared about 25 million years ago, and spread across Africa and Eurasia. But that long evolutionary legacy may not last much longer. Okapis, which live in the forests of Central Africa, are currently listed as endangered and are subject to hunting and habitat loss. And late last year giraffes, which most conservationist did not worry too much about, were listed as vulnerable. Their numbers have dropped 40 percent over the last 30 years due to poaching and habitat loss.
But perhaps, discoveries such as the new four-horned species will remind us just how unique—and worthy of protection—these animals truly are.