Press release: Fossil find: Ancient evidence for present-day deep-sea organisms furnished
Nr. 186/2012 - 12.10.2012
114 million-year-old fossils of marine fauna discovered – study with scientists from the University of Göttingen
(pug) The deep-sea is not only the largest, but also the least investigated habitat on Earth. The geological evolution of present-day deep-sea organisms in particular poses a true conundrum. Working off the coast of Florida, an international team of researchers from the University of Göttingen succeeded in identifying approximately 114-million-year-old fossils of deep-sea organisms and compared them with their present-day relatives. Their study showed that a large portion of today’s deep-sea ecosystems is significantly older than had previously been assumed. The full results are published in the scientific journal PLoS ONE.
The generally accepted of the past few years has been that today’s deep-sea ecosystems evolved from several drastic changes in the wake of mass extinctions and global changes within the oceans. Thus, they ought to be relatively young – in geological terms. However, it has not yet been possible to verify this assumption because fossil remains of deep-sea organisms are an extremely rare finding. All of the recently discovered fossils stem from echinoderms, for example sea urchins, starfish and brittle stars, which are very common in our present-day deep seas and full of diversity, and were retrieved from deep-sea sediments drillings. ”We usually search these samples for the remains of small unicellular creatures in order to reconstruct earlier climate events,” says Ben Thuy, lead author of the study from the Center for Geosciences of the University of Göttingen. “It was a big surprise to find that these samples contained remains of larger marine animals from the deep sea. These fossils provide a unique window into the history of the deep sea that has never been open to us before.”
The research team – consisting of scientists from the University of Göttingen, the Natural History Museum in Vienna, the Naturhistoriska Riksmuseet in Stockholm, the MARUM – Center for Marine Environmental Sciences in Bremen and the University of Portsmouth – was able to prove that the fossilised deep-sea organisms are strikingly similar to their present-day descendants. From these findings, the researchers conclude that modern ecosystems existed in the deep sea much earlier than previously assumed. This suggests that the deep sea is less susceptible to mass extinctions and changes of global proportions (for example climate change) than the more shallow oceanic areas. “Even with the last major upheavals occurring in the oceans during the Cretaceous and in the later Palaeocene periods, there must have been environments within the deep sea where the organisms could retreat to”, Ben Thuy explains.