Biologists: humans have genes of sea monsters who extincted a billion years ago

Half a billion years ago, headless sea creatures that looked more like tree leaves, feathers or skeins of rope roamed the primeval seas. It is difficult to imagine that they can be related to us. However, according to new research, some of the most important human genes may be relics of the genes of those creatures extincted long ago, LiveScience informes.

The organisms that inhabited the Earth in the Ediacaran period (635-542 million years ago) looked completely otherworldly by our standards - flat branching creatures prowling in search of food on the seabed. Some of them resembled leaves so much that scientists argued for decades whether they could be attributed to animals.

Most of the Ediacaran biota were slightly more advanced organisms than sponges: they had nerves and intestines - but in that era they represented a huge evolutionary leap. They were the first multicellular organisms, which means the distant ancestors of all modern animals.

In a new study, geologists and biologists from the University of California and the National Museum of Natural History in Washington, DC, examined fossils from four genera of Ediacaran biota found in Australia. It turned out that they are not that different from modern animals. Despite the absence of heads and legs, they were characterized by such features as body segmentation and side symmetry. This suggests that many of the most important genes of modern animals, called regulatory genes, were also in these ancient creatures. Developmental evolutionists know that everyone with front and back or left and right have the same genetic makeup.

The researchers also suggested that many of the genes responsible for more complex traits, such as nerves and muscles, were probably also present in the genomes of the Ediacaran biota. It appears that many of these animals were actively foraging for food rather than passively filtering it out of the environment. This may suggest that they had genes responsible for a vestigial nervous system and sensory organs that allowed their hosts to detect and collect food from the seabed.

In addition, some of the fossils have scars. This suggests that the Ediacaran biota was able to repair its damaged tissues during programmed cell death. These functions are controlled by genes that are integral to the immune system of animals.

The research is published in the journal Proceedings of the Royal Society B.