Biodiversity of a Unique Environment: The Southern Ocean Benthos Shaped and Threatened by Climate Change.

• Main Authors: Brandt, A., Gutt, J.
• Format: Other/Unknown Material
• Language: English
• Published: 2011
• Subjects: Southern Ocean; Antarc*; Antarctica
• Online Access: http://hdl.handle.net/11858/00-001M-0000-0017-D55C-8

Over millions of years, plate tectonics, palaeoceanography and the resulting changes in the global climate (greenhouse to icehouse) have impacted the Southern Ocean marine fauna and flora, caused evolutionary extinctions and radiation of benthic marine invertebrates, and led to the present biodiversity. Simultaneous biogeographical events happening were the progressive retraction of cosmopolitan taxa established during the Jurassic and Cretaceous periods when Antarctica was still under greenhouse conditions. The disjunctive distribution patterns resulted from vicariance due to the disintegration of the supercontinent Gondwana. Active migration of taxa in and out of the SO (depending on dispersal capabilities) caused a change in biodiversity composition of several invertebrate taxa over geological time scales including the period after the geomorphological isolation established. It is assumed that life on the seabed has not been completely erased at any time in the geologic past, although some taxa vanished while others thrived or radiated. Nowadays, natural and anthropogenically driven climate change processes shape the Southern Ocean marine fauna and we can only anticipate the threat associated with these changes because the processes driving speciation as well as biodiversity changes are not fully understood yet. Images