Arctic dinosaurs have a new poster child.
Ugrunaaluk kuukpikensis, a new species of duck-billed dinosaur, lived in what is now Alaska some 69 million years ago, scientists report September 22 in Acta Palaeontologica Polonica.
A geologist first discovered Ugrunaaluk fossils weathering out of a bluff in 1961. “It took 20 years before anyone actually realized the bones were from a dinosaur,” says Patrick Druckenmiller, a paleontologist at the University of Alaska Fairbanks.
Scientists began expeditions to the bluff in the 1980s and have since discovered thousands of bones buried in mud and siltstone permafrost. But the skeletons had busted apart, and the bones came mostly from youngsters — so figuring out which species 
were represented was tricky.
Years spent cataloging and comparing bones convinced Druckenmiller’s team that the Cretaceous Arctic had a new species, joining about a dozen other known dinosaurs from the region. The duck-billed dinos lived in polar forests, where yearly temperatures probably averaged around 4°Celsius, he says, roughly as cold as a refrigerator. Living conditions may have been tough: After round-the-clock daylight in the summer, winter would have plunged the dinosaurs into long stretches of darkness.
Adults may have reached nine meters in length, about the length of two full-sized cars parked end to end.
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