Reorganization of Southern Ocean plankton ecosystem at the onset of Antarctic glaciation.

Publisher: American Association for the Advancement of Science Country of Publication: United States NLM ID: 0404511 Publication Model: Print Cited Medium: Internet ISSN: 1095-9203 (Electronic) Linking ISSN: 00368075 NLM ISO Abbreviation: Science Subsets: MEDLINE

Publication: : Washington, DC : American Association for the Advancement of Science
Original Publication: New York, N.Y. : [s.n.] 1880-

Adaptation, Physiological* ; Ecosystem* ; Ice Cover* ; Oceans and Seas*; Dinoflagellida/*physiology ; Phytoplankton/*physiology ; Zooplankton/*physiology; Animals ; Antarctic Regions ; Cold Temperature ; Fossils

The circum-Antarctic Southern Ocean is an important region for global marine food webs and carbon cycling because of sea-ice formation and its unique plankton ecosystem. However, the mechanisms underlying the installation of this distinct ecosystem and the geological timing of its development remain unknown. Here, we show, on the basis of fossil marine dinoflagellate cyst records, that a major restructuring of the Southern Ocean plankton ecosystem occurred abruptly and concomitant with the first major Antarctic glaciation in the earliest Oligocene (~33.6 million years ago). This turnover marks a regime shift in zooplankton-phytoplankton interactions and community structure, which indicates the appearance of eutrophic and seasonally productive environments on the Antarctic margin. We conclude that earliest Oligocene cooling, ice-sheet expansion, and subsequent sea-ice formation were important drivers of biotic evolution in the Southern Ocean.

Date Created: 20130420 Date Completed: 20130430 Latest Revision: 20130419

20231215

10.1126/science.1223646

23599491