Evaluating combat in ornithischian dinosaurs.

Ornithischia, a diverse clade of herbivorous dinosaurs, has numerous members with structures hypothesized to function in combat. These include the horned ceratopsids, dome-headed pachycephalosaurs, spike-thumbed iguanodonts, tail-clubbed ankylosaurs and spiked stegosaurs, among others. Three main lines of evidence support such inferences: (1) analogy with modern animals; (2) biomechanical analysis and simulation; and (3) paleopathology. The most solid inferences utilize multiple pieces of evidence, although this is hampered by a limited understanding of combat in modern animals. [ABSTRACT FROM AUTHOR]