A marine microfossil from the Foraminifera phylumWIKIMEDIA, HANS GROBE/AWIBy sequencing DNA recovered from deep-sea sediments in the South Atlantic, researchers have discovered previously unknown marine microorganisms that lived up to 32,500 years ago. The findings, published this week (May 8) in Current Biology, suggest that genetic material recovered from sea floor sediments can shed light on the ecological history of the oceans and climate change.
A team of scientists from several European countries took cores of mud from the abyssal plains in the middle of the South Atlantic, a barren patch of ocean floor 5,000 meters below the surface. When they sequenced DNA from the samples and compared the results with known sequences from Foraminifera and Radiolaria—two groups of marine microorganisms well represented in the microfossil record as well as living taxa—the researchers identified 169 Foraminifera species and 21 Radiolaria, many of which were unknown. Furthermore, a significant portion of the Foraminifera species identified belonged to groups that do not form fossils.
The results show that it’s possible to study species not contained in the fossil record, which could bring new insights into ocean history and climate change, study author ...