Scientists continually uncover new facets of Earth’s history, and a recent find may represent the earliest known multicellular animal.
The fossil was unearthed in the Ediacara Hills of South Australia’s Nilpena Ediacara National Park, a region renowned for its 555‑million‑year‑old assemblages of early life. Assistant Professor Scott Evans of Florida State University and a multidisciplinary team of paleontologists identified the organism, now named Quaestio simpsonorum.
Evans described the creature as roughly palm‑sized, with a distinctive question‑mark–shaped body that clearly separates left from right. Its thin, membranous exterior would have linked resilient tissues across a subtle left‑right asymmetry – a level of organization unprecedented among Ediacaran fossils.
Evidence from trace fossils suggests the animal was motile, moving along the seafloor much like a Roomba vacuum while absorbing nutrients – likely microscopic algae and bacteria – directly through its skin. Harvard graduate student and coauthor Ian Hughes noted that the presence of a trace fossil behind a specimen confirmed its ability to locomote.
Nilpena Ediacara National Park has been a focal point for paleontological research for decades. The discovery of Quaestio simpsonorum at a fresh dig site, in partnership with South Australia Museum volunteers, offers unprecedented insight into the rise of complex life before the Cambrian explosion.
“Determining the gene expressions that built these forms provides a new method for evaluating the mechanisms behind the emergence of complex life on Earth,” Evans said. Park lead scientist Mary Droser, who has guided excavations for over twenty years, added that understanding such early life helps test evolutionary theories and may even inform the search for life beyond our planet.
The team plans to revisit previously excavated sites, eager to uncover further details. Hughes remarked that even though Quaestio simpsonorum belongs to one of the world’s earliest animal ecosystems, the fossil record indicates a remarkable diversity and a burst of life during that era.
For more details, see the original study published in Evolution & Development (link to journal).
