Antarctica Ice Cap Came into Existence 3.6 Million Years Ago: Study

An interesting finding reveals that the ice cap of Antarctica came into existence some 3.6 million years ago during the Oligocene epoch, according to a news release.

The discovery was based on data retrieved from an international expedition led by the Andalusian Institute of Earth Sciences (IACT), a Spanish National Research Council-University of Granada joint center. Researchers came up with the findings after analyzing information contained in the ice sediments from various depths.

The study states that the Earth was a warm place with a tropical climate before the ice covered Antarctica. The region was rich in plankton diversity. However, their population suffered and dropped in number during the glacial period. Those that managed to adapt to the new climate were the ones that survived.

"The fossil record of dinoflagellate cyst communities reflects the substantial reduction and specialization of these species that took place when the ice cap became established and, with it, marked seasonal ice-pack formation and melting began," says IACT researcher Carlota Escutia, who led the expedition.

The phytoplanktons that are visible today are the ones that appeared during the formation of the ice caps at Antarctica, and have survived the changes. The ice cover at Antarctica is extremely seasonal: during summer, there is very little ice, as the ice caps melt. The melting of the ice caps increases the production of the plankton community that resides in the region. The melted ice reappears and the frozen ice expands to an area equal to that of Antarctica during the winter. When the ice melts, the trapped nutrients are freed and are used by the plankton. This event influences the dynamics of global primary productivity.

Ever since the ice first expanded across Antarctica and supported the community of dinoflagellate to survive, these species have been exposed to constant change and evolution.

"The great change came when the species simplified their form and found they were forced to adapt to the new climatic conditions," says Dr. Escutia.

The details of the findings have been published in the journal Science.