Is this strange, three-horned extinct creature a giraffe cousin?

Scientists classify the Eurasian Miocene ruminant Palaeomerycid in the same clade as giraffes in new research.

Courtesy of Israel M. Sánchez
This is a reconstruction of X. amidalae. Illustration by Israel M. Sánchez.
Courtesy of Israel M. Sánchez
Study co-author María Ríos with the holotype of Xenokeryx amidalae (a complete occipital region of an adult male with the occipital appendage).

Palaeomerycidae, a family of strange, horned extinct creatures that roamed Eurasia in the middle Miocene, have long been thought to be ancestors of deer.

But the odd ancient animals also display similar features to another ungulate – the giraffe. 

Both deer and giraffes are ruminants, herbivores with multiple stomachs for complex digestion, and both animals have horns. 

But Palaeomerycid’s horns, say scientists, among other characteristics, show that the ancient animal is more closely related to the giraffe, not the deer.

Fossils found in Spain of Xenokeryx amidalae, a Palaeomerycid species that lived in the middle Miocene epoch, some 16 to 11 million years ago, helped researchers classify the ancient ruminant as a member of the clade Giraffomorpha in a new paper published Wednesday in the journal PLOS ONE

Xenokeryx has three horns, two small ones in the front of its head and a large T-shaped horn protruding from the back. The scientists found that the front horns are ossicones, the same structure that gives giraffes their horns. 

An ossicone is a detachable unit. In a young animal, it grows separately and then fuses to the skull in adulthood. 

“The problem with Palaeomerycids is that really nobody knew where they belonged in the ruminant evolutionary tree,” study author Israel M. Sánchez tells The Christian Science Monitor in an interview. 

Scientists had previously connected Palaeomerycids to another group of ruminants that appear similar externally and whose teeth have features like those of Palaeomerycids. These other ruminants, the Dromomerycids, are thought to be distant deer relatives.

“The majority of researchers thought that Palaeomerycids in Eurasia and the Dromomerycids in North America were very closely related groups,” Dr. Sánchez says. So Sánchez and his colleagues turned to Xenokeryx to test that hypothesis.

“We have discovered that Palaeomerycids in Europe were not the cousins of the North American Dromomerycids,” he says.

The problem before was that conclusive fossil evidence for ossicones in Palaeomerycids had not yet been found.

But now, “They found evidence, finally, that separates the North American from the Eurasian animals into two different groups,” Nikos Solounias, a mammalian anatomy and evolution expert who has focused his research on giraffes and is not connected with this study, tells the Monitor in an interview. “They look very similar,” he says. But, “that’s called convergent evolution.”

In convergent evolution, different animals independently evolve similar traits as a process of adapting to similar environments. 

Xenokeryx was classified as a member of the clade Giraffomorpha based on its physical characteristics. 

Cladistics – the means of classifying biological organisms based on shared derived characteristics – "is more or less like the stock market,” says Dr. Solounias. “It’s what you define it to be. You look at characters and match animals with characters.” 

“Cladistics is looking at similarities, so it’s not surprising that they’re finding those relatives to the giraffe,” Solounias says. In fact, he adds, other researchers have pointed out those similarities before. 

This study is “reassuring, yes, they’re relatives to the giraffes,” says the giraffe expert. 

Solounias estimates that the common ancestor of Palaeomerycid and the giraffe lived some 19 million years ago. 

“The giraffes need to have another group next to them,” evolutionarily, Solounias says. “They cannot be by themselves, hanging.” 

Solounias hopes that identifying that lineage could help answer questions about the giraffe’s origins.

The long-necked, long-legged animal has few close living relatives. They are one of “a very, very diverse group full of strange animals,” Sánchez says. Research into the giraffe’s lineage could help scientists and conservationists better understand the animals.

“It’s our responsibility that the giraffe doesn’t go on to be studied [only] by paleontologists, doesn’t go extinct,” Sánchez says.

You've read  of  free articles. Subscribe to continue.
Real news can be honest, hopeful, credible, constructive.
What is the Monitor difference? Tackling the tough headlines – with humanity. Listening to sources – with respect. Seeing the story that others are missing by reporting what so often gets overlooked: the values that connect us. That’s Monitor reporting – news that changes how you see the world.

Dear Reader,

About a year ago, I happened upon this statement about the Monitor in the Harvard Business Review – under the charming heading of “do things that don’t interest you”:

“Many things that end up” being meaningful, writes social scientist Joseph Grenny, “have come from conference workshops, articles, or online videos that began as a chore and ended with an insight. My work in Kenya, for example, was heavily influenced by a Christian Science Monitor article I had forced myself to read 10 years earlier. Sometimes, we call things ‘boring’ simply because they lie outside the box we are currently in.”

If you were to come up with a punchline to a joke about the Monitor, that would probably be it. We’re seen as being global, fair, insightful, and perhaps a bit too earnest. We’re the bran muffin of journalism.

But you know what? We change lives. And I’m going to argue that we change lives precisely because we force open that too-small box that most human beings think they live in.

The Monitor is a peculiar little publication that’s hard for the world to figure out. We’re run by a church, but we’re not only for church members and we’re not about converting people. We’re known as being fair even as the world becomes as polarized as at any time since the newspaper’s founding in 1908.

We have a mission beyond circulation, we want to bridge divides. We’re about kicking down the door of thought everywhere and saying, “You are bigger and more capable than you realize. And we can prove it.”

If you’re looking for bran muffin journalism, you can subscribe to the Monitor for $15. You’ll get the Monitor Weekly magazine, the Monitor Daily email, and unlimited access to

QR Code to Is this strange, three-horned extinct creature a giraffe cousin?
Read this article in
QR Code to Subscription page
Start your subscription today