Eukarya/eukaryotes unicellular

Higher organisms were believed to be unable to withstand extreme environments most probably because of their cellular complexity and compartmentalization. Therefore research on extremophiles has focused mainly on organisms belonging to the Archaea and Bacteria kingdoms. However, a significant number of eukaryotes, both unicellular and multicellular, have evolved to live and thrive in extreme environments (e.g. Alvinella pompejana, Tetrahymena thermophila and Dunaliella salina). Hence, extremophiles span all three domains of life Archaea, Bacteria and Eukarya [61]. 

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