Bizarre structures in dinosaurs: species recognition or sexual selection? A response to Padian and Horner

Exaggerated structures in dinosaurs, such as horns and crests, primarily evolved for mate competition rather than species recognition. This conclusion challenges the alternative hypothesis proposed by Padian & Horner (2010), which suggested these traits facilitated social interactions like herding or mating. The study counters this by highlighting the lack of evidence for sexual dimorphism in dinosaur species and the absence of directional evolution in exaggerated traits, both key predictions under the species recognition model. Instead, strong positive allometry and delayed ontogenetic development of these structures align with patterns seen in sexually selected traits of extant animals, such as beetles and bovids. The research emphasizes the importance of rigorous phylogenetic context and assessing multiple hypotheses to understand the adaptive functions of dinosaurian traits.

Knell, R. J., & Sampson, S. (2010). Bizarre structures in dinosaurs: species recognition or sexual selection? A response to Padian and Horner. Journal of Zoology, 283(1), 18–22. Portico. https://doi.org/10.1111/j.1469-7998.2010.00758.x