Not having eye, brain, usu, even anal, deep-sea worm is successfully baffled biologists for more than 60 years. What and where this type of thing should have been in the family tree.
With features such as socks and purple, and some members of the external body, scientists have little information about this worm. This worm was originally classified as flatworms, then there is proposed entry mollusk family. Some suggest going in the vertebrate family, while others even propose echinoderm family entrance.
During the discovery of four new species, the scientists conducted DNA tests that indicate the worm is actually an early form of what is now known as bilateral animals. This means, in this strange creature in the mirror symmetry, unlike humans, anemones, and jellyfish that had some body symmetry.
Reporting from Iflscience, Friday (02/05/2016), after a long debate, scientists are entering this creature into Xenoturbella groups, ie groups that are in the earliest genealogical tree. It showed that this creature is actually a primitive creature that can survive until now.
In a recent study published in Nature, Xenoturbella first discovered in 1949 off the coast of Sweden. Until now, it has unspecified four species that live in the deep sea with strong pressure, which is about 3,700 meters above sea level.
Although scientists managed to collect some samples from the seabed, researchers still have not been able to determine what they actually eat. Which makes the experts are confused even though it has no teeth and digestive organs, these creatures can eat hard-shelled mollusk.source