Trilobites emerged 513 million years ago, are the ancestors of spiders and crustaceans

Sep 25, 2013 19:01 GMT  ·  By

Some 513 million years ago, odd-looking creatures known to the scientific community as trilobites thrived in nearly all regions of our planet.

Recently uncovered fossil evidence suggests that, much like armadillos do nowadays, these animals used to curl up in a ball whenever they felt that they were in danger and that they needed to protect themselves from predators.

Live Science tells us that, while analyzing hundreds of trilobite fossil remains, paleontologist Javier Ortega-Hernández at the University of Cambridge in England and his fellow researchers noticed that one of these creatures had some weird-looking spines sticking out from its head.

Upon closer investigation, it was revealed that these spines were actually its tail, which the animal had flexed under its head.

Although this behavior has been documented in younger trilobite specimens, researchers were surprised to find that trilobites first started rolling up in self-defense millions of years earlier than previously assumed.

“Until now, it was thought that this group was incapable of enrolling, as they lack various of the complex adaptations observed in younger trilobites,” Javier Ortega-Hernández explains.

“It turned out that this case was millions of years older than the previously known oldest occurrence, and thus became very significant for understanding the origin of this complex strategy in trilobites,” he adds.