A newfound dinosaur species may not have been burdened with the glorious purpose of Loki — but it did bear an impressive set of horns reminiscent of the helmet of the trickster god of Norse mythology.
Fossils of the new specimen, dubbed Lokiceratops rangiformis, were unearthed in Montana’s badlands. The dinosaur lived about 78 million years ago, when the now-arid region was a swampy floodplain bordering a vast seaway within western North America, paleontologist Mark Loewen and colleagues report June 20 in PeerJ. The name, they say, means “Loki’s horned face that looks like a caribou.”
The most distinctive feature of the dinosaur is its two large, bladelike horns, jutting forward and out from between its eyes. Those two horns — like the horns of modern caribou or reindeer — have different lengths. The arrangement of the horns, as well as the ornamentation along the edge of the creature’s bony neck frill at the back of its head, is distinct from that of other species of horned dinosaur known to exist in the same region and around the same time, the scientists report.
“It’s becoming more clear that [horned dinosaurs] were using these [bony features] as ornaments, in order to attract mates, or intimidate rivals of the same species,” says Loewen, of the University of Utah in Salt Lake City. That sort of differentiation in ostentatious ornamentation “is the kind of thing that evolves on an island,” he says — like the bright, distinct plumage of birds.
The new study suggests that this diversity could be due to the relative isolation of this ancient swampland, cut off from other parts of the mainland by the seaway. Lokiceratops, Loewen says, would make the fifth species of large, horned dinosaur found in the Kennedy Coulee, a dry gorge with exposed fossil-bearing rocks that spans what’s now northern Montana and southern Alberta, Canada. Other identified species of ceratopsids include close relatives Medusaceratops, Wendiceratops and Albertaceratops, as well as a smaller species of ceratopsid called Avaceratops lammersii (SN: 7/8/15). “It’s the highest ceratopsian diversity known in any one place,” Loewen says.
But other researchers are not convinced that Lokiceratops represents a new species. It’s possible, says paleontologist Denver Fowler, that the differences in bony ornamentation between Lokiceratops, Albertaceratops and Medusaceratops aren’t indicative of individual species, but of evolving ornamentations within a single species.
The differences may even represent age-related changes among individuals, says Fowler, of the Dickinson Museum Center in North Dakota.
The Lokiceratops specimen is “a very large, and a very mature, old individual,” he says. Previous research on other ceratopsids, particularly the well-known Triceratops, have revealed that “these animals can change significantly as they grow.” He also notes that the bladelike brow horns of Lokiceratops are hollowed out — a feature also seen in the biggest, oldest specimens of Triceratops, compared with the more solid horns of the younger specimens.
Lokiceratops does appear to be very closely related to Albertaceratops and Medusaceratops, based on the arrangement of bony ornamentations on the dinosaurs’ frills, says Shawn DeNarie, a paleontologist specializing in ceratopsids at George Washington University in Washington, D.C. But the orientations of the frill horns appear to be different enough to suggest they may be distinct species, says DeNarie, who was not involved in the new study.
This is not the first time that researchers have pondered whether two closely related ceratopsid specimens represent two separate species, or whether one is just a juvenile version of another. A similar debate flared over the individuality of Triceratops and Torosaurus (SN: 3/9/12). Albertaceratops and Medusaceratops, too, have been considered by some scientists to be the same species.
“When we have opposing views, we have to highlight them,” Fowler adds. “As we get more data, we’ll get closer to the truth.”
In the meantime, this does seem like the sort of obfuscation that a god of mischief might particularly enjoy. So perhaps Loki is having the last laugh.
source site