美国犹他州发掘出新种多角恐龙

"A giant rhino（犀牛）with a ridiculously supersized head." "Fifteen long, pointed sideways oriented eye horns: one over the nose, one atop each eye, one at the tip of each cheek bone, and ten across the rear margin of the bony frill."

"A horned face: large horn over the nose and short, blunt eye horns that project strongly to the side."

Such phrases have been used to describe two newly discovered species of dinosaurs with looks only a mother could love. Still, they are drawing the attention and inspiring the imagination of scientists and lay people alike.

Announced today in PLoS ONE, the online open-access journal produced by the Public Library of Science, two new species of horned dinosaurs--Utahceratops gettyi and Kosmoceratops richardsoni--have been found in Grand Staircase-Escalante National Monument in southern Utah. Close relatives of the famous Triceratops, these giant plant eaters were once inhabitants of the "lost island continent" of Laramidia, a swampy（沼泽的，湿地的） , subtropical setting formed when a shallow sea flooded the central region of North America, isolating the eastern and western portions of the continent for millions of years during the late Cretaceous period.

"My enthusiasm for these findings is threefold," said Raymond Bernor, program director of the Sedimentary Geology and Paleobiology（古生物学） Program at the National Science Foundation (NSF). "First, researchers discovered two new, exciting dinosaur species. Second, the research has accomplished a major advance in understanding the biogenographic provinciality（乡下习气，粗鄙） of Western North American dinosaur communities that apparently included separate northern and southern populations. And third, this discovery has inspired future discoveries in the Grand Staircase-Escalante National Monument, which has now emerged as one of the most important paleontological reserves in the world."

But what about these ugly, horned creatures … Although much speculation has ensued（跟着发生） about the function of the ceratopsia（角龙） horns and frills of these prehistoric monsters--from fighting off predators to recognizing other members of the same species or controlling body temperature--the dominant idea today is that these features functioned first and foremost to enhance reproductive success. Scott Sampson, first author on the paper, explains, "Most of these bizarre features would have made lousy（讨厌的） weapons to fend off（避开，挡开） predators. It's far more likely that they were used to intimidate or do battle with rivals of the same sex, as well as to attract individuals of the opposite sex."