Almost twenty years after fluffy little Sinosauropteryx hopped onto the scene, the existence of feathery dinosaurs is no longer much of a surprise. Paleontologists have found evidence of body coverings from “dinofuzz” to flight feathers on a score of non-avian dinosaur species, ranging from the pigeon-sized, magpie-patterned Anchiornis to the 30-foot long Yutyrannus. But despite this flood of fossil discoveries, paleontologists are still puzzling over the bigger questions behind the plumage. Among the most pressing is when these downy splashes of fluff and fuzz first evolved. A newly-named dinosaur found in Siberia only complicates the question.

Late last year, at the annual Society of Vertebrate Paleontology meeting in Los Angeles, experts and