Cambrian Explosion: early segmented worm (Introduction)

by David Turell , Friday, December 11, 2015, 00:03 (3058 days ago) @ David Turell

About 530 million years ago, a worm with head, a mouth cone, teeth and an armored segmented body.-http://www.sciencedaily.com/releases/2015/12/151210112135.htm-"Dubbed Eokinorhynchus rarus -- or rare ancient mud dragon, the newly discovered animal dates back from the Cambrian period and contains five pairs of large bilaterally placed spines on its trunk. It is believed to be related to modern kinorhynch"-***-"Kinos represent an animal group that is related to arthropods -- insects, shrimps, spiders, etc. -- which are the most diverse group of animals on the planet," said Xiao, who refers to kinorhynchs as "kinos" for short. "Although arthropod fossils date back to more than 530 million years ago, no kino fossils have ever been reported. This is a huge gap in the fossil record, with more than 540 million years of evolutionary history undocumented. Our discovery is the first report of kino fossils."-"Xiao added that the new fossil can tell scientists more about how and why body segmentation evolved many times among not only arthropods, but several other groups of animals. Scientists believe kinos and arthropods should have evolved more than 540 million years ago. More so, the authors found that E. rarus has a number of similarities with living kinorhynchs, suggesting a close evolutionary relationship.-"Similarities between the fossils of E. rarus and living, modern kinorhynchs include their hollow spines arranged in a five-fold symmetry and their body segments each consisting of articulated plates. However, E. rarus differs from modern species with more numerous segments. Hence the belief of an ancestorship."-Comment: Again, much more complex than any Ediacaran animals