Buzz
Unlike the green chlorophyll we see today, which gives plants their color, ancient chlorophyll was dark red and purple, lending a pinkish hue to the earth and seas. Luis Diaz Devesa/Getty ImagesKey Takeaways
- Unlike the green chlorophyll we have today, ancient chlorophyll found in bacterial fossils was dark red and purple, giving early Earth and its oceans a pinkish tint.
- Researchers have discovered this pink pigment in cyanobacterial fossils found in the Sahara Desert, suggesting that over 650 million years ago, these bacteria dominated Earth’s oceans.
- This early pink coloration, a result of the diluted pigments from ancient cyanobacteria, is now recognized as the world’s oldest-known color, contrasting with our modern view of blue oceans and green plant chlorophyll.
What color is the ocean? Naturally, blue, right?
But this wasn't always the case. If you imagine prehistoric oceans as being blue like today, you'd be mistaken. Scientists have discovered that ancient oceans actually had a rosy tint, making pink the oldest color known to man.
Researchers uncovered the tiny pink pigment in bacterial fossils from the Sahara Desert in Mauritania, West Africa. The cyanobacteria, which thrived on sunlight, were believed to have been the dominant life form in Earth’s oceans over 650 million years ago. Cyanobacteria likely preceded algae, once considered a fundamental element in the evolution of larger life forms, as found in a study published on July 9, 2018, in the journal Proceedings of the National Academy of Sciences.
So what made these tiny microbes embrace pink? It wasn’t a style choice. The fossilized chlorophyll within the bacteria was dark red and purple when concentrated, meaning that when diluted by water or soil, it gave Earth and the seas a pinkish hue. This is different from modern chlorophyll, which today gives plants their green color, according to researchers from the Australian National University, where the bacterial fossils were studied.
Though it's rare for ancient chlorophyll to be preserved, these samples were likely created when a cyanobacteria bloom quickly sank to the ocean floor, protected from oxygen molecules that speed up decay. After sinking, the microbes eventually fossilized, and the rock they formed part of remained undisturbed — and intact — for a billion years.
Through the process of photosynthesis, plants rely on chlorophyll, the green pigment found in nearly every plant, to absorb and convert energy into the nutrients they need for survival.
