The fossils range from blood red to deep purple in their concentrated form, and bright pink when diluted and are more than half a billion years older than previous pigment discoveries. The rocks deep beneath the Sahara desert in Africa, remnants of an ancient ocean that has long since vanished, were rocks to powder (yes, you read that right, but nature has a lot more) before extracting and analyzing molecules of ancient organisms from them.
The emergence of large, active organisms was likely to have been restrained by a limited supply of larger food particles, such as algae. Algae, although still microscopic, are a thousand times larger in volume than cyanobacteria, and are a much richer food source..
"The precise analysis of the ancient pigments confirmed that tiny cyanobacteria dominated the base of the food chain in the oceans a billion years ago, which helps to explain why animals did not exist at the time," said Dr Nur Gueneli from Australian National University in a statement.
The cyanobacterial oceans started to vanish about 650 million years ago, when algae began to rapidly spread to provide the burst of energy needed for the evolution of complex ecosystems, where large animals, including humans, could thrive on Earth.