An international team of scientists has discovered that a well-preserved fossilized worm dating back 518 million years resembles the ancestor of three major groups of living animals.
Scientists from the University of Bristol and Oxford and the Natural History Museum found that the 1.2 cm long fossils discovered in China belonged to a strange armored worm carrying bundles of barbed bristles on its sides, and dense plates on its back intertwined in a regular pattern, which crawled on the ground for more than half a year. A billion years ago, during a period known as the Cambrian explosion, it was called the Wufengella, a short creature that belonged to an extinct group of shellfish called tommotiids.
Scientists say that this organism had a fleshy body with a series of flat lobes protruding from the sides, and bundles of hairs appear from the body between the lobes and plates.
The numerous lobes, bundles of hairs, and the group of plates on the back are evidence that the worm was originally sequential or segmented, like the earthworm.
The scientists added that this discovery sheds light on the evolution of three main groups of living animals.
The findings were published in the journal Current Biology, with study co-author Dr Jacob Venther from the University of Bristol’s School of Earth Sciences saying: ‘It appears to be an unlikely lineage between the hairy worms (or polycilia) and the chiton mollusc. Interestingly, she does not belong to either of these groups.”
