Fire amoeba discovered in California breaks heat record for complex life

Scientists have discovered a new species of amoeba, Incendiamoeba cascadensis, which sets a new heat-tolerance record for eukaryotes. Found in the geothermal waters of Lassen Volcanic National Park in California, the organism—nicknamed the “fire amoeba”—is capable of reproducing through cell division at 63 degrees Celsius (145 degrees Fahrenheit).

This discovery, published in the journal Cell, challenges previous scientific assumptions that complex life forms with nuclei and membrane-bound organelles could not remain stable above 60 degrees Celsius. While the amoeba stops reproducing above 63 degrees, it remains active and can move to find food at up to 64 degrees Celsius. It can also survive brief exposure to temperatures as high as 70 degrees Celsius by entering a protective dormant state.

Research led by microbiologists at Syracuse University and supported by NASA indicates that the amoeba utilizes specific genetic adaptations to survive. These include genes that help stabilize DNA, maintain protein folding, and protect cell membranes from degradation. The findings have implications for astrobiology, potentially expanding the understood boundaries of where complex life might exist in extreme environments on Earth and other planets.