Researchers believed that the menacing bony frills and horns on a Triceratops's head serve as a protection from enemies.
New research suggests something entirely different -- these horns are for attracting mates.
Ceratopsian dinosaurs including Triceratops and Styracosaurus are known for their exaggerated horns and frills. These armors vary between species.
A study published in the Proceedings of the Royal B provides a different explanation about the purpose of these elaborate armors.
There are several theories as to why dinosaurs possess these head crests. One theory explains these features as an ornamental trait; another considered the crests as a defense mechanism against predators. The latest explanation is that these horns are for sexual selection or signaling mates.
Among all these theories, the prevailing notion is that the head crests exist as a result of species recognition. This concept maintains that species living in the same environment evolve to develop features to distinguish them from each other and avoid unfit offsprings through crossbreeding or hybridization.
The new research ruled out species recognition and supported the theory of sexual selection.
Sexual selection refers to an organism's ability to obtain or copulate with a mate. Male peacocks displaying their elaborate tails, elephants fighting over territories, and fruit flies performing dances are some examples of sexual selection.
Sexual selection is important in maintaining biodiversity, and it plays an important role in determining how new species evolve.
Scientists said sexual selection could promote rapid speciation, adaptation, and extinction. It may also have a significant contribution to the conservation of living things.
A previous study in 2016 first identified sexual selection in dinosaurs. The latest study affirms the earlier theory.
Scientists from the Queen Mary University School of Biological And Chemical Sciences in London said the features they saw in Protoceratops matches common signaling structures in other species.
The latest study states that the horns of dinosaurs are formed to attract potential sexual partners. Dinosaurs develop these traits to show off to potential partners.
"Palaeontologists have long suspected that many of the strange features we see in dinosaurs were linked to sexual display and social dominance but this is very hard to show, says Dr. David Hone, a lecturer in Zoology from Queen Mary University.
The team of researchers studied the horns and fossil records of 46 species of ceratopsians.
"We have shown that species recognition, one of the commonest explanations, is unlikely to be responsible for the diversity or origin of ornamentation in this group," according to Andrew Knapp, Ph.D. candidate from the School of Biological and Chemical Sciences, and lead author of the study.
Ceratopsia is a major clan of non-avialan dinosaurs with 70 known species, all of which possessed large, ornamented, morphologically diverse skulls.