While your favorite colors and hues have theoretically always existed, some colors have existed in nature far longer than others. A team from the Australian National University (ANU) have stumbled upon what they believe to be the oldest geological colors on record.
These bright pink pigments existed over 1.1 billion years ago in the rocks found deep in the Sahara Desert in Africa.
Oldest colors on Earth
Nur Gueneli and the team from ANU noted the pigments were discovered and collected from marine black shales of a basin in Mauritania, West Africa. The new colors outdate the previous record holder of the oldest pigment by more than half a billion years. Gueneli made the discoveries as part of her larger PhD work.
But what caused such a unique color scheme? Ancient organisms and time, the researchers explained.
"The bright pink pigments are the molecular fossils of chlorophyll that were produced by ancient photosynthetic organisms inhabiting an ancient ocean that has long since vanished," said Gueneli from the ANU Research School of Earth Sciences.
In order to figure out the colors and study the rock contents more easily, the ANU team had to crush their billion-year-old samples into a fine powder. They then extracted and analyzed the molecules found from ancient organisms that were attached to the rocks.
"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," Dr Gueneli said.
Associate professor Jochen Brocks from ANU noted the development of large organisms was probably restrained by a lack of larger food particles.
"Algae, although still microscopic, are a thousand times larger in volume than cyanobacteria, and are a much richer food source," said Brocks, who works in the ANU Research School of Earth Sciences.
Brocks explained this is an ancient process, but piecing together major events in Earth's geological history helped them date their color discovery.
"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."
The entire work from the ANU team can be found in a recent version of the Proceedings of the National Academy of Sciences of the United States of America (PNAS).