Here's a somewhat simplified phylogeny of dinosaurs:
- Saurischia ("lizard hipped")
- Theropoda -- tyrannosaurs, birdlike dinosaurs, birds themselves
- Sauropoda -- the giant ones with long necks
- Ornithischia ("bird hipped")
- Thyreophora
- Neornithischia
- Kulindadromeus
- Ornithopoda, including duckbilled ones
- Marginocephalia, including Ceratopsia, the ones with horns and neck frills
Kulindadromeus is a basal neornithischian, and featherlike structures have also been found in some other ornithischians. That raises a big question about the evolution of feathers featherlike structures. Most dinosaurs found to be feathered have been theropods, but this new one is rather distant from the theropods. So did some ancestral dinosaur have feathers? Or did dinosaurs evolve feathers more than once?