The oldest known "footprints" left by an animal have been uncovered in southern China.
The identity of the creature that made the 546-million-year-old tracks is still unknown, but they come from the period when the earliest animals are thought to have evolved.
The fossil consists of two rows of imprints that represent the earliest known record of an animal with legs.
The research by a Chinese team appears in Science Advances journal.
Team-members are unclear whether the creature had two legs or several. But they say the tracks probably belong to a bilaterian.