In addition, an analysis of T. katalepsis' anatomy revealed what other characteristics made mandibulates so successful. For instance, its more than 50 body segments were an important adaptation for mandibulates, "as it allowed for the development of additional segments and structures at and around the base of the limb, called 'coxae,' and from which the mandibles themselves likely [arose]," Aria said.
The new finding is only the latest fossil discovery from Marble Canyon. Other Cambrian fossil discoveries there include an ancient fish known as Metaspriggina and a four-eyed arthropod called Yawunik.
The finding is a potential novel perspective on the evolution of arthropods, said Jakob Vinther, a paleobiologist at the University of Bristol in England, who was not involved with the study. However, he cautioned that because the fossils are flattened, they might be difficult to decipher. [Cambrian Creatures Gallery: Photos of Primitive Sea Life]
"Finding mandibles is a key finding for understanding the evolution of myriapods, crustaceans and insects," Vinther said. "I hope that the observations can be validated by other researchers also in the near future."
However, another paleobiologist, Peter Van Roy at Ghent University in Belgium, who was also not involved with the study, called the study and interpretation of the material "well-supported from what I can see."
Van Roy added that "these fossils elucidate the early evolution of this very important clade [group], which so far was poorly understood, and underscore the importance of exceptionally preserved fossils for resolving phylogenetic [family tree] questions in deep time."
The study was published online today (April 26) in the journal Nature.
Original article on Live Science.
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