The Adaptive Radiation of Notothenioid Fishes in the Waters of Antarctica

Abstract

Fishes of the perciform suborder Notothenioidei, which dominate theichthyofauna in the freezing waters surrounding the Antarctic continent, representone of the prime examples of adaptive radiation in a marine environment. Driven byunique adaptations, such as antifreeze glycoproteins that lower their internal freezingpoint, notothenioids have not only managed to adapt to sub-zero temperaturesand the presence of sea ice, but also diversified into over 130 species. We herereview the current knowledge about the most prominent notothenioid characteristics,how these evolved during the evolutionary history of the suborder, how theycompare between Antarctic and non-Antarctic groups of notothenioids, and howthey could relate to speciation processes.