Chinese archaeologists have discovered a batch of fossils of multicellular eukaryotes that date back to 1.63 billion years ago, setting the world's oldest record of such fossils.
These well-preserved microfossils, Qingshania
The discovery was made by researchers from the Nanjing Institute of Geology and Palaeontology under the Chinese Academy of Sciences. It marks another advancement after they found decimeter-sized fossils of multicellular eukaryotes in this region in 2016, and pushes back the emergence of such organisms by about 70 million years.
The newly found fossils consist of large uniseriate and unbranched filaments with cell diameters up to 190 micrometers. A particular feature, the round intracellular structure in some cells, indicates that they might reproduce by spores, like many eukaryotic algae. Researchers further inferred that the fossils were most likely photosynthetic algae.
The earliest eukaryotic fossils so far are unicellular forms dating back to 1.65 billion years ago found in north China and north Australia. Qingshania magnifica appeared slightly later, indicating that eukaryotes evolved to multicellularity very early in their history, said the paper.