The researchers performed the analysis of digital reconstructions of the limbs to find out how much stress they could handle. For comparison, they did the same for another ancient arthropod, Sidneyia uneppectans – a well-known mussel breaker – as well as the horseshoe crab. They then compared the results.
They found that O. serratus was likely unable to break into peeled creatures – its long spines would have broken, said Dr. Bicknell. Instead, these spikes were likely used to break up detritus and soft prey like worms, just like we might peel apart steamed fish with a fork.
However, R. rex was apparently built to crush. According to the analysis, its limbs could withstand more strength than those of the horseshoe crab. It might have specialized in consuming shelled prey, including other trilobites and even other redlichia, said Dr. Bicknell.
This type of virtual experimentation allows deeper insight into “the function of anatomical parts that otherwise cannot be tested,” said Karen Moreno, a paleontologist at Austral University of Chile who was not involved in the study.
But because certain information – such as the muscle positions of a trilobite or the material properties of its exoskeleton – is unknown and has to be approximated, precise measurements and clear conclusions are impossible. By making comparisons with creatures we understand better, like the horseshoe crab, experts can “look for patterns – approximations that will fuel future research.”
When asked if he would like to answer some of these questions once and for all – for example, through a time-traveling snorkeling excursion – Dr. Bicknell yes.
“The Cambrian was effective when arthropods ruled the world,” he said. “It would be just so nice to see – beautiful might not be the right word. But interesting. “