The Antarctic drilling vessel JOIDES Resolution was used in the Integrated Ocean Drilling Program to dig deep into Antarctic sediments.
The modern ecosystem of icy Antarctica is some 33.6 million years old,
new research finds, with a system dating back to the formation of the
polar ice caps.
The date is revealed by fossilized remnants of plankton found in Antarctic
sediments, which show how plankton diversity plummeted when a big chill
came along at the end of the Eocene Epoch and the beginning of the
Oligocene Epoch. Before the transition, Earth was a toastier place, and a wide array of plankton survived even at the poles.
The study, published in the journal Science in April, focused on
single-celled plankton called dinoflagellates, which contain materials
that fossilize. Before the Eocene-Oligocene transition about 34 million
years ago, Antarctic dinoflagellates were extremely diverse. When the
ice pack formed, however, only plankton that could survive cold
temperatures and a seasonal freeze-melt cycle remained.
For the rest of the story: http://www.livescience.com/34759-antarctica-ecosystem-age-found.html
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