The discovery of a billion-year-old multicellular alga

Specialists from the University of Liege (Belgium) discovered transformed remains of chlorophyll in a microfossil found in the Congo River basin. The organism he left is one of the oldest photosynthetic eukaryotes found in the fossil record.

The emergence of photosynthesis was a major step in the evolution of life, as it allowed to absorb a lot of energy and radically change the conditions on Earth. Very little is known about the first such organisms, as they are hardly represented in the fossil record, and identification of their metabolites in fossils is key to discovering these ancient life forms.

Scientists led by Marie Svorna used X-ray absorption spectroscopy on synchrotron radiation sources to discover traces of such metabolism in carbon films of fossil rock.
The analysis showed the presence of nickel porphyrins in Arctacellularia tetragonala cells that are about 1 billion years old.

“We identified these fragments as chlorophyll derivatives, indicating that tetragonala-A was a photosynthetic alga, the first of its kind,” the authors wrote.

The new methodology will provide paleontologists with additional opportunities to study organisms that are about a billion years old and will allow to explore the evolution of life on a new level.

The corresponding article was published in Nature Communications.