Russell Bicknell, a paleontologist at the University of New England in Australia, has discovered what may well be the earliest evidence of cannibalism in our planet’s history, Live Science reports.
According to the media outlet, Bicknell made this find while examining fossilised remains of trilobites from the Emu Bay Shale formation on Kangaroo Island.
The formation in question contained two species of trilobites from the same genus that existed millions of years ago, with one of them, Redlichia takooensis, being a deposit feeder, and the other, Redlichia Rex, being a larger and predatory species.
And while the discovery of what appears to be bite marks on R. takooensis fossils, as well as trilobite shell remains in the fossilised feces of R. rex suggest that the latter trilobite species were capable of eating the former, the signs of similar bite marks on R. rex seem to hint that these ancient predators could also feast on their own kind.
"There's not much else in this deposit that has the toolkit, is biomechanically optimised for this kind of thing, and could willingly crunch down on something hard," Bicknell said.
The paleonthologist and his colleagues have so far managed to “systematically remove” all explanations other than cannibalism for these injuries found in trilobite fossils, the media outlet notes.
"What you're left with is this almost demonstrable record of cannibalism, just short of going back in time and watching it happen," Bicknell remarked.
He also suggested that cannibalism may be far older than their find would suggest, and much more widespread to boot.
"I would go as far as to say that arthropods have been eating arthropods since the dawn of arthropods becoming arthropods," he said.