Among the human ancestors was a worm

scientists are willing to put an end to the dispute about who can be considered the first chord. This two-inch worm-like creatures Pikaia gracilens, lived in the water 500 million years ago and is the ancestor of modern vertebrates, including humans.

As scientists discovered in Cambridge, Pikaia gracilens could swim quite briskly. On both sides of the chord they had a muscular tissue, which allowed the body to bend from side to side. Pikaia had eyes and teeth, but the heads are clear enough. They breathe using gills with. In Pikaia gracilens it was also two small tentacles, which are believed to researchers, allowed them to determine the chemical composition of the water to find food.

To understand all this has helped scientists to analyze 114 fossils of Pikaia gracilens, found in the Rocky Mountains in Canada, he wrote. The researchers used a number of new technologies - such as scanning electron microscopes, the ability to show the smallest details.

via factroom.ru