A 3D model of a Walliserops trifurcatus trilobite, which sports a unique trident at the front of its head. (Alan D. Gishlick)
CBC Radio's Quirks and Quarks had a recent segment about trilobites. New research published in the journal Proceedings of the National Academy of Sciences suggests a use for the large forks that some trilobites grew on their heads.
A species of ancient trilobites grew big forks on their heads to fight their opponents and impress potential mates, in what scientists say could be the earliest known example of ritualized combat.
A new study published in the Proceedings of the National Academy of Sciences suggests that one trilobite species used a strange appendage on its head for sexual selection — and most likely for fighting other male trilobites.
Though they've been extinct for 250 million years, trilobites were one of the most successful and diverse animal groups ever — dominating the ancient oceans for hundreds of millions of years. All trilobites shared certain traits — like a three-lobed body — and visually resembled modern woodlice or pillbugs, ranging in size from a few millimetres to the size of a sea turtle.
But a striking feature of one trilobite species, Walliserops trifurcatus, stands out from the rest: at the front of its head was a trident-like structure as long as the trilobite's body. This trident has made Walliserops a popular find among fossil collectors and an evolutionary puzzle for biologists.
"The trilobite's fork most resembled the structures of animal weapons involved in a type of fighting behavior that's been characterized as shoveling," Alan Gishlick, assistant professor at Bloomsburg University and one of the study authors, told Quirks & Quarks.
