An article published in the journal “Nature Ecology & Evolution” offers an answer to the arguments about the most ancient group of animals appeared on Earth. According to a team of evolutionary biologists at Vanderbilt University and the University of Wisconsin-Madison ctenophores were the first animals and not sponges, as many believe. This conclusion was reached by comparing a set of genes of 18 branches of the living beings’ family tree using 6 of animals, plants and fungi as a control branches.