Another 2016 study used laser-stimulated fluorescence imaging to analyze the internal structure of the bristles. The highly cornified bristles were arranged in tight clusters of three to six individual bristles, with each bristle being filled with pulp. The authors considered the bristles as being most similar to the quills of "Tianyulong", and the sparsely distributed elongated broad filamentous feathers (EBFFs) of "Beipiaosaurus". Similar, non-feather-derived bristles are found in a few extant birds such as the "horn" on the horned screamer and the "beards" of turkeys; these structures differ from feathers in that they are unbranched, heavily cornified and do not develop from a follicle, but instead arise from discrete cell populations that exhibit continuous growth. A darkened soft-tissue structure was also found near the jugal horn; this may represent a keratinous sheath or a skin flap.