Back when the dinosaurs ruled the Earth, some hardy bacteria took up residence at the bottom of the Pacific Ocean. Eighty six million years later, they're still there. And a new study says they're living out the most Spartan lifestyle known on this planet.
They live in a place called the Pacific Gyre, where almost nothing reaches the seafloor. Nutrients from the world's rivers don't get out that far. Most plankton that die in the water dissolve long before any pieces of them can reach the seafloor far below. It's a rare day indeed when even a single particle lands in any given spot on the bottom.
"If you imagine that a grain of sediment falls on the surface, it will take a thousand years before the next grain will sit on top of it," says Hans Roy at Aarhus University in Denmark.
As a result, it has taken millions of years for a thin layer of sediment to form.