However, until now, no records of such fossils were ever found. Researchers from the Chinese Academy of Sciences' Nanjing Institute of Geology and Palaeontology, together with colleagues from Virginia Tech in the U.S., studied the trackways and burrows that were discovered in a fossil-rich area close to the Yangtze River.
Chinese team researched about it and it appeared in Science Advances Journal.
Both the footprints and the borrows are known as "trace fossils", a term that refers to fossilized remnants that animals leave behind, such as fossilized poop, rather than fossils of the animals themselves. But what they can say, with reasonable certainty, is that the tracks probably belong to a bilaterian.
Scientists have discovered the earliest footprint of an animal on Earth, dating back 541 million years. The rocks they come from are dated to between 551 million and 541 million years old.
"Previously identified footprints are between 540 and 530 million years old", Dr Zhe Chen from the Nanjing Institute of Geology and Palaeontology told MailOnline. Bilaterians are a group of animals that have paired appendages - in this case, paired legs.
Bilaterians are one of the most common body types in the world, now and throughout history, but previous fossil evidence for them only goes back as far as the Cambrian. The trackways also indicate a connection to burrowing, suggesting that whatever animal made the tracks might have had a habit of digging into sediments.
"The footprints are organized in two parallel rows, as expected if they were made by animals with paired appendages".
Now, the discovery of the trackways and burrows shows that animals with appendages lived during the Ediacaran period, the researchers said.
As modern arthropods and annelids served as appropriate analogs for the interpretation of this fossil, the researchers posit the animal in question could be the ancestor of either of the two groups.
"This style of preservation is distinct from other types of trace fossils, for example, tunnels or burrows, or body fossils".