558-million-year-old fossil confirmed as the oldest animal ever

Scientists from the Australian National University (ANU) have made a very incredible discovery that confirmed the earliest animal life in the geological record. The team says that the animal lived on the Earth 558 million years ago and is called Dickinsonia. This fossilized animal lived on Earth 20 million years before the "Cambrian explosion" of modern animal life.

The fossil shows a rather strange creature that grew to 1.4 meters in length and had an oval-shaped body with rib-like segments running its length. It looks rather like a leaf. The fossil was found in a remote area near the White Sea in Russia and it was so well preserved its tissue still contained a type of fat that is a hallmark of animal life. That fat is cholesterol.

Scientists say that the Cambrian explosion is when complex animals and macroscopic organisms like worms, sponges, and others became dominant in the fossil record. Scientists have been debating for years whether Dickinsonia and other fossils from the Edicaran Biota were giant single cell amoeba, lichen, or animals.

The fat discovered in the new fossil has now settled that debate claiming Dickinsonia as the oldest known animal fossil. Scientists had been trying for years to find Dickinsonia fossils that retained some organic matter.

Prior to the discovery of the Russian fossil, other fossilized specimens of Dickonsonia were from the Ediacara Hills in Australia and were damaged by weather and having endured heat and pressure. The new fossil was in the middle of a cliffside to be 60 to 100 meters high and the scientist had to use ropes to dig out blocks of sandstone to find fossils. Grueling work, but the discovery is a significant one.

SOURCE: Phys.org