New breakthrough research from Virginia Tech University shows complex multi-celled life existed at least 600 million years ago, rewriting the standing scientific narrative on the evolution of more sophisticated lifeforms.

Findings of the recent study, published online in the journal Nature, contradicts the longstanding belief that multi-celled life during that period comprised relatively simple creatures, such as bacteria, single-cell eukaryotes, algae, sea sponges, sea anemones, or bilaterally symmetrical animals.

"This paper lets us put aside some of those interpretations" Shuhai Xiao, a professor of geobiology in the Virginia Tech College of Science, said in a news release. "This opens up a new door for us to shine some light on the timing and evolutionary steps that were taken by multi-cellular organisms that would eventually go on to dominate the Earth in a very visible way."

Xiao and collaborators from the Chinese Academy of Sciences looked at phosphorite rocks from the Doushantuo Formation in central Guizhou Province of South China and recovered three-dimensionally preserved multi-cellular fossils that showed signs of cell-to-cell adhesion, differentiation and programmed cell death -- qualities typically associated with more complex multi-cellular eukaryotes, including animals and plants.

That discovery positions more developed multi-celluarity 60 million years before creatures with skeletons began roaming the earth, amid the giant surge of new life known as the Cambrian Explosion.

Xiao, who earned his bachelor's and master's degrees from Beijing University in 1988 and 1991 and his doctoral degree from Harvard University in 1998, said he undertook the research to determine how, why and when multi-celled creatures arose from their single-celled ancestors.

While some hypotheses can now be discarded, several interpretations -- like the notion multicellular fossils like the ones he found served as transitional forms related to animals or multi-cellular algae -- may still endure, Xiao said. That's why, he added, his future research will focus on a broader paleontological search to reconstruct the complete life cycle of the fossils.