Tubular structures found in black shale from a quarry in Gabon providing evidence of the earliest-known mobile organisms on Earth. Life emerged in Earth's seas as single-celled bacterial organisms perhaps 4 billion years ago, but the earliest life forms lacked the ability to move independently, called motility. The Gabon fossils are roughly 1.5 billion years older than the previous earliest evidence of motility and appearance of animal life. The tubular structures, up to 170mm long, originally were made of organic matter, perhaps mucus strands left by organisms moving through mud. The evolutionary experimentation with motility may have encountered a setback relatively soon after the Gabon organisms lived because of a dramatic drop in atmospheric oxygen 2.08 billion years ago.

Source: Otago Daily Times February 11, 2019 21:11 UTC