Previous theories suggested that dinosaurs that lived in the same areas tended to develop frills and horns so that they could recognize each other more easily. According to the theory, they also wanted to avoid producing unhealthy offspring due to hybridization. A group of researchers from Queen Mary University in London analyzed the horns of 50 ceratopsian species to see if there were any differences. They published their paper in the Proceedings of the Royal Society B, with the paper suggesting that none of those horns displayed specific diversity between the species that shared their habitat and those that lived elsewhere.
The new study put an end to previous theories and studies. On the other hand, the researchers are now convinced that horns on dinosaurs formed not so much as an armor feature but more so to advertise themselves as a sexual partner. The horns supposedly helped them determine whether they were sexually compatible. Lead author, Andrew Knapp, a PhD candidate from Queen Mary University’s School of Biological and Chemical Sciences told BBC News in an interview, that this trait of dinosaurs is similar to how peacocks attract their mating partners with the help of their tail feathers.
According to BBC News, the reason the previous theories suggesting that the horns on dinosaurs were there to help them recognize their own species and to prevent interspecies mating were ruled out is because only “subtle indications” are needed to differentiate between species. Also, the features that separate two species are not that drastically different.
The researchers originally focused on ceratopsians during their study. However, they believe that their theory can be applied to other prehistoric creatures. Computer modeling that is used today suggests that sexual selection in certain species could promote “rapid speciation, adaption, and extinction,” and those simulations could implicate conservation and preservation of endangered species.
“If sexual selection is indeed the driver of ornament evolution in ceratopsians, as we are increasingly confident it is, demonstrating it through different lines of evidence can provide a crucial window into tracing its effects over potentially huge timescales,” Knapp explained in a statement.
Knapp and his team will attempt to discover more evidence of socio-sexual selection being the reason for horns on dinosaurs, as well as frills and other ornaments. Knapp told BBC News that the theory of species recognition is rather impossible as there are not many signs of such behavior, and that there might be a “more innate understanding” which enable herds of animals to recognize similar species.