During a series of expeditions in northern Greenland researchers unearthed a fossil showing an ancient arthropod that swam the oceans five hundred and twenty million years ago. As you can imagine, this half a billion year old creature looks absolutely terrifying. The creature is around one full meter in length, and has twelve stubby feet with a mouth that shows several rows of teeth. Scientists have long disagreed about where this particular specimen came from. One theory suggests that this ancient arthropod's mouth could only have come from a particular sea-creature that was the largest sea-predator during the Cambrian period. Another theory states that the fossil is simply showing a common form of marine life during the Cambrian period. Eventually scientists from the University of Bristol successfully determined the identity and origins of the fossilized creature. The scientists discovered that the portion of the strange looking mouth matched the remains of a mouth on another specimen that had been identified as "Pambdelurion," which is a type of arthropod that lived during the Cambrian period. Since the fossil is 520 million years old, and only a partial piece of the extinct animals mouth remains, could it be accurately determined what type of animal was fossilized?