Ghostly imprints of tiny plankton-like creatures have been found haunting the sediments of prehistoric oceans at a time when such organisms were thought to be extinct. The so-called nannofossil imprints reveal that the organisms survived acidic oceans caused by climate change, and could offer a clue for how modern creatures can endure rising ocean temperatures, researchers said.
Nannofossils are the remains of marine plankton called coccolithophores (cox-oh-LITH'-oh-fours), which belong to the class Prymnesiophyceae and still exist today at the bottom of many ocean food chains. Each of these single-celled, algae-like organisms measures less than 0.001 inch (30 micrometers) wide, and is surrounded by a hard layer of geometric calcium scales, according to the Faculty of Geosciences at the University of Bremen in Germany. And these nannofossils are incredibly abundant.
"There are way, way more nannofossils than any other kind of fossils," Paul Bown, a micropaleontologist at University College London, U.K., and co-author of the new study, told Live Science. "It means we can really be statistically robust, because we see so many of them."
