Scientists have discovered what could be the oldest animal footprint fossils ever found.
The tracks were found in southern China’s Yangtze Gorges and date back up to 551 million years ago.
This is potentially 10 million years before the Cambrian Explosion, which is when creatures capable of leaving tracks like this were thought to have come into existence.
The tracks were discovered by scientists from the Chinese Academy of Sciences’ Nanjing Institute of Geology and Palaeontology, together with colleagues from Virginia Tech in America.
The scientists do not know what sort of animal left the tracks.
Dr. Shuhai Xiao of Virginia Tech told The Independent: “We explicitly stated in the paper that we do not know exactly what animals made these footprints, other than that the animals must have been bilaterally symmetric because they had paired appendages.”
“At least three living groups of animals have paired appendages—arthropods such as bumble bees, annelids such as bristle worms, and tetrapods such as humans.
“Arthropods and annelids, or their ancestors, are possibilities; and modern arthropods and annelids provide appropriate analogue to guide our interpretation of these fossils.
“But unless the animal died and preserved next to its footprints, it is hard to say with confidence who made the footprints.”