![image: [ The fossils are believed to show the world's oldest multi-cellular organisms ]](/olmedia/50000/images/_53672_fossils300.jpg)
The fossils, which include algae, sponges and animal embryos almost 600 million years old, were discovered in rocks in southern China.
One of the scientists, Professor Andrew Knoll, of Harvard University, says the find could provide important new insights.
"What has captured our imagination is the fact that there are beautifully preserved multi-cellular algae that show complex patterns of anatomical development and primitive biology," he said.
"And perhaps of greatest interest to most people, we have actually found preserved embryos of early animals."
At 580 million years old, the fossils are 20 million years older than specimens found in Australia.
Chen Junyuan, Professor with the Nanjing Institute of Geology and Paleontology, is quoted by the Xinhua news agency as saying: "These are believed to be the earliest multi-cellular animals living on the earth.
"They existed 20 million years before the Ediacaran Biota found in Australia, which was previously regarded as the earliest such animal.
"The discovery could lead to significant breakthroughs in exploring the evolution of early life on the globe."
The fossils have been named the Weng'an fossils after the county is south-western Guizhou province where they were found.
They measure between 0.5 millimetres (0.02 inches) and 0.75 millimetres (0.03 inches) across.
Andrew Knoll home page
Guizhou Source
The Fossil Page
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