Arctic and Antarctic Scleractinian Corals: Comparisons—Similarities and Differences

Abstract

Fauna of the circumpolar Arctic and Antarctic regions was compared based on the example of cold-water Scleractinia corals. In similar subzero temperatures of surrounding waters, not only the distribution of corals, but also the number of species and their morphological characteristics differ radically between the Arctic and Antarctic (17 coral species occur in the Subantarctic region, including six endemic species, whereas the Arctic and high latitudes are inhabited by two species). We believe that the difference between these two faunas is due to the difference in geological history of these regions. In the southern hemisphere, the formation of Antarctic circumpolar currents ended before the Neogene. Stable conditions that existed for several million years in the Subantarctic region led to the formation of well-developed scleractinian fauna and species endemic to this area. In the Northern Hemisphere, stable hydrological conditions at high latitudes and in the Arctic have existed since the beginning of the Holocene for approximately 11–12 ka, when colonization by corals species with a wide distribution began. Indirect evidence on the vertical thickness of the Circumantarctic current ring is presented.