It's not every day one gets to describe a new species of dinosaur, so Caleb Brown decided to make the most of it.
In a scientific paper published Thursday in the journal Current Biology, Dr. Brown, who is a researcher with the Royal Tyrrell Museum in Drumheller, Alta., ended with a question directed at fellow paleontologist Dr. Lorna O'Brien:
"Lorna will you marry me?"
Happily, Dr. O'Brien said yes, Dr. Brown confirmed. But, true to his scientist's heart, he added: "We don't want that part to eclipse the new species."
As it happens, the new species appears decked out for a celebration. It is a horned dinosaur, a forerunner of Triceratops, but with an unusually elaborate frill that resembles a bony tiara.
According to Dr. Brown, the creature's elegant ornamentation, together with its place in geologic time – 68 million years ago – makes it an outlier in horned dinosaur evolution.
"Most researchers would not have predicted that this particular animal with this suite of characteristics would have existed in the time that it did," he said.
The species is known only through a single, spectacular skull, measuring over a metre and a half long. It was discovered in 2005 by Peter Hews, a petroleum geologist and an amateur fossil hunter, while hiking along the Oldman River, south of Calgary. Mr. Hews spotted the creature's snout protruding from a steep cliff along the river and alerted the museum. An arduous extraction process followed, that included airlifting the skull, still encased in a giant block of stone, back to the museum.
Because of the stubby horns above the skull's eye sockets and the difficulty involved in retrieving it, the specimen was nicknamed "Hellboy," a character from comic-book and action-movie fame. Now, after years of study and painstaking preparation, Dr. Brown and his colleagues are set to unveil Hellboy together with its newly minted official name, Regaliceratops peterhewsi (a nod to the museum's royal charter and the fossil's discoverer).
Horned dinosaurs were herbivores and are among the most common of the giant reptiles that once roamed the planet. Although Triceratops is the most recent and, by far, the best known, a few dozen types have been uncovered and there is some ongoing debate about which finds are truly separate species.
In North America, the horned dinosaur split into two distinct lineages about 80 million years ago. One group, the centrosaurines, are distinguished by their fancy frills and short horns. The curious thing is that Regaliceratops showed up well after the centrosaurines died out. It's a member of the other line, which eventually led to Triceratops, but it seems to have a centrosaurine appearance.
Dr. Brown and his colleagues suspect it's a case of convergent evolution. Regaliceratops evolved to take on a particular appearance that was no longer the signature look of another line of horned dinosaurs at that time.
What was the point of such distinctive features? The general consensus among experts is that it was a way for the animals to signal each other, possibly with elaborate markings in addition to the frills. But exactly what message they conveyed, whether a basic species identifier or something more subtle, is an open question.
Regaliceratops adds complexity to the picture, and also samples a time period and an ecosystem that paleontologists know little about. Although Alberta is well-known for its dinosaur fossils, they mostly belong to a different period and they are found further to the north and east of where Regaliceratops showed up, in the foothills of the Rockies.
Michael Ryan, curator of vertebrate paleontology at the Cleveland Museum of Natural History, who was not involved in the find, said the jury was still out on the role of signalling and the evolutionary story behind Regaliceratops. But he said the discovery suggests that there were plenty of gaps left to fill in.
"Maybe Regaliceratops is telling us that there's hidden diversity at that time slice in Alberta and there's yet more horned dinosaurs to find," he added.
Whether or not such hypothetical new discoveries will also lead to more romantic signalling among paleontologists remains to be seen.
Joseph Caputo, a spokesman for Current Biology's publisher, Cell Press, based in Cambridge, Mass., said that Dr. Brown's marriage proposal to Dr. O'Brien was a first for the journal and "we wish the very best for the couple."