section_path: Biodiversity/Other organisms
section_name: Other organisms
paragraph_text: Other organisms
  
  Of the 700 species of algae in Antarctica, around half are marine phytoplankton. Multicoloured snow algae are especially abundant in the coastal regions during the summer. Even sea ice can harbour unique ecological communities, as it expels all salt from the water when it freezes, which accumulates into pockets of brine that also harbour dormant microorganisms. When the ice begins to melt, brine pockets expand and can combine to form brine channels, and the algae inside the pockets can reawaken and thrive until the next freeze. Bacteria have also been found as deep as 800 m (0.50 mi) under the ice. It is thought to be likely that there exists a native bacterial community within the subterranean water body of Lake Vostok. The existence of life there is thought to strengthen the argument for the possibility of life on Jupiter 's moon Europa, which may have water beneath its water-ice crust. There exists a community of extremophile bacteria in the highly alkaline waters of Lake Untersee. The prevalence of highly resilient creatures in such inhospitable areas could further bolster the argument for extraterrestrial life in cold, methane -rich environments.