Speaker 1: Welcome to brain Stuff production of I Heart Radio. Hey
Speaker 1: brain Stuff, Lauren Vogelbaum. Here, we all know that the
Speaker 1: ocean is blue, or sometimes a nice blue green, or
Speaker 1: during storms and inky blue black. But this wasn't always
Speaker 1: the case. Prehistoric oceans were not blue like they are today.
Speaker 1: The scientists have discovered that ancient oceans were actually a
Speaker 1: rosy hue, making pink the world's oldest known color created
Speaker 1: by living things. The researchers, who published their findings in
Speaker 1: the journal Proceedings of the National Academy of Sciences back
Speaker 1: in found the pink pigment in bacteria fossils that date
Speaker 1: back one point one billion years in what's now part
Speaker 1: of the Sahara Desert in Mauritania, West Africa, but was
Speaker 1: once a vast ocean. The fossils were of tiny cyana bacteria,
Speaker 1: which are single celled organisms that are thought to have
Speaker 1: survived on sunlight, using an ancient form of chlorophyll to
Speaker 1: capture the light energy and convert it into food. These
Speaker 1: cyana bacteria were the dominant life form in Earth's oceans
Speaker 1: for eons. They seem to even predate algae, which have
Speaker 1: only been traced back about six hundred and fifty million years.
Speaker 1: The bacteria were so small and so prevalent that the
Speaker 1: researchers think they actually prevented larger life forms from evolving
Speaker 1: for hundreds of millions of years because there are thousand
Speaker 1: times smaller than even tiny algae. It wasn't until algae
Speaker 1: started taking over that there was enough of a food
Speaker 1: source for larger, more active organisms to thrive. But what
Speaker 1: made these little microbes think pink? The fossilized chlorophyll inside
Speaker 1: the bacteria was concentrated into dark red and purple hues,
Speaker 1: But in pulverizing and studying the bacteria molecules, the researchers
Speaker 1: found the pigment to be a brilliant, bright pink, which
Speaker 1: means that when diluted by water or soil, it would
Speaker 1: have lent a pink cast to earth and sea. This
Speaker 1: is unlike modern chlorophyllm, which today is the bright green
Speaker 1: compound that lets plants turn light into food and gives
Speaker 1: most plants, from trees to grass to cabbage their green color.
Speaker 1: While it is rare for ancient chlorophyll to be preserved,
Speaker 1: these samples were probably formed when a bloom of Cyana
Speaker 1: bacteria quickly sank to the sea floor, where the environment
Speaker 1: was lacking the oxygen molecules that bolster decay. Once they sank,
Speaker 1: the microbes eventually fossilized, and the rock they became part
Speaker 1: of remained motionless and in one piece for a billion
Speaker 1: years for the researchers to make this discovery. Today's episode
Speaker 1: is based on the article Earth's oldest color was pink
Speaker 1: on how stuff works dot Com, written by Lori l. D.
Speaker 1: Brain Stuff is a production of I Heart Radio in
Speaker 1: partnership with how stuff works dot Com, and it is
Speaker 1: produced by Tyler Play four more podcasts from my heart
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