The record for the oldest color pigment has been shattered by a recently discovered fossilized chlorophyll inside ancient rocks.
The oldest color pigment was first recorded back in 1993 and was found to be about 500 million years old. At the time, it was considered the earliest example of porphyrins, the molecular building blocks of chlorophyll.
However, an international team of researchers recently discovered a preserved signature for chlorophyll hidden inside black shales dug out of the Taoudeni Basin in Mauritania, West Africa. The organic pigment is said to be 1.1 billion years old – 600 million years older than the existing record holder.
What’s even more interesting was after crushing and diluting the raw material, it was found to be a shade of pink. Yes. Billions of years ago, Earth was not black and white after all.
Furthermore, the researchers believe that the microscopic organism that left it behind might have been more vibrant in color.
“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,” Nur Gueneli of the Australian University and lead author of the study, said.
According to studies, the Earth’s oxygen level started to rise around 3.4 billion years ago. Scientists believed that oxygenic photosynthesis – the process that gave plants its green color – could have evolved soon after life itself.
While the latest findings gave scientists a better glimpse of the colors that dominated our young planet billions of years ago, it also left a huge question mark about the existence of plants as we know them today.
The discovery of the 1.1 billion-year-old pink pigment left researchers with a significant gap in fossil evidence of sunlight-harvesting pigments.
Still, the molecular structure of the sample has given researchers significant clues about the organisms that created them. In fact, the specific isotope of nitrogen it contains revealed that the organisms were not plant-like at all.
“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,” Gueneli went on to say.
Still, cyanobacteria were not considered a strong enough source of nourishment, giving way to the argument that bigger and more complex organisms were not around during that time because of the lack of food supply.
“Algae, although still microscopic, are a thousand times larger in volume than cyanobacteria, and are a much richer food source,” Jochen Brocks, one of the ANU researchers, explained.
“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.”
Gueneli and his team’s research study was published in the journal Proceedings of the National Academy of Sciences.