“…541-Ma Shibantan Member deposited in a subtidal environment between fair-weather and storm wave bases (15,18). Like other trace fossils from the same locality and horizon, they exclusively occur in beds characterized by crinkled microlaminae, which are interpreted as microbial mats, suggesting intimate ecological interactions between the trace makers and the mats (13,15,19). These microbial mats comprised a few millimeters of sediment and may have also helped trace fossil preservation (20,21).…”