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Research on early animal evolution timeline

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2026-10-14 01:09 UTC → 2026-10-19 22:34 UTC · added ~~removed~~

An international research team led by the University of Oxford has proposed that animal life may have evolved between 700 and 800 million years ago, potentially 100 to 200 million years earlier than the current consensus of approximately 574 million years ago. To reach this conclusion, scientists utilized molecular clock techniques to measure genetic mutations and analyzed chemical traces, such as lipid biomarkers. The research involved analyzing over 140 samples from the Kheseen Biota in Mongolia. Researchers argue that the historical absence of fossils in certain deposits, such as the Weng’an Biota in China, does not definitively prove the absence of animals, as soft-bodied organisms are difficult to fossilize and may have inhabited different environments, including regions like Namibia and southern China. By using reference sites in Norway, Australia, and Arizona, the team estimated this earlier timeline, which suggests complex life could have emerged prior to the ‘Snowball Earth’ glacial periods. Lead author Orin Lole Durbin noted that while the analysis pushes the timeline back, it does not provide “absolute proof” of animal existence at the 800-million-year mark. Recent findings published in Science Advances support this earlier timeline through the analysis of more than 140 microfossils from the Kheseen Biota. Using scanning electron microscopy, the team examined microscopic structures, including some that resemble embryos with preserved internal cells. While the high state of preservation allowed for the observation of details rarely seen in ancient organisms, researchers noted that none of the specimens can be definitively identified as animals yet. These findings provide new temporal references for the molecular clock technique.

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