LIVE SCIENCE - The earliest known animal to show evidence of an asymmetrical body lived over half a billion years ago in what is now the Australian outback, a new study reports.
The 555 million-year-old creature, dubbed Quaestio simpsonorum in a study published Sept. 3 in the journal Evolution and Development, was able to move around on the ocean floor like a "small marine Roomba vacuum," eating microscopic algae and bacteria. But this seemingly simple animal hid an exciting discovery: the unique "backward question mark"-shaped protrusion on its back is the first recorded example of an asymmetrical body pattern, a vital step in the evolution of complex life.
The fossils were discovered in South Australia's Nilpena Ediacara National Park, a fossil deposit that has been excavated for decades. Many of the earliest complex animal fossils have been found in the remote desert hills of Nilpena Ediacara National Park, but nothing like Quaestio had ever been seen before, the new study's researchers said.
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"It’s incredibly insightful in terms of telling us about the unfolding of animal life on Earth," Mary Droser, a paleontologist at the University of California, Riverside and lead author of the study, said in the statement. "We’re the only planet that we know of with life, so as we look to find life on other planets, we can go back in time on Earth to see how life evolved on this planet."