HISTORY
World’s oldest case of cannibalism revealed
WORDS CAMERON DUKE
An artist’s impression of trilobites on the seafloor
Before there were dinosaurs, there were trilobites brutally biting each other on the Cambrian seafloor. New research has revealed that these armoured predators didn’t only hunt smaller and weaker animals for food, but would occasionally take bites out of trilobites of the same species. This finding represents the earliest evidence of cannibalism in the fossil record to date. Trilobites are now-extinct marine arthropods that first appeared in the fossil record around 541 million years ago. They were stout creatures with thick exoskeletons, which is likely one of the reasons so many trilobite fossils remained preserved all these years; exoskeletons fossilise much easier than softer tissues. Russell Bicknell, a palaeontologist at the University of New England in Australia, spent five years examining trilobite fossils from the Emu Bay Shale formation on Kangaroo Island in South Australia. There are two trilobite species from the same genus found in this formation: Redlichia takooensis, a deposit feeder that ate particles on the ocean floor, and the larger, predatory R. rex.