Volcanic Amoeba Grows at Record Heat for Complex Life
Researchers discovered an amoeba in geothermal waters at Lassen Volcanic National Park that can grow and reproduce at 63°C, exceeding the previous roughly 60°C limit for eukaryotes. It can also survive up to 70°C by changing form and developing a protective outer layer.
From 2023 to 2025, researchers collected microbes from geothermal streams in Lassen Volcanic National Park, where sampled waters ranged from roughly 47°C to 64°C. The newly named Incendiamoeba cascadensis showed strong growth at 57°C and was seen dividing at 63°C, indicating active reproduction, not just endurance.
The earlier eukaryotic growth boundary sat near 60°C, whereas the archaeon Methanopyrus kandleri can grow at 122°C. Above 63°C, this amoeba alters its morphology and forms a shielding exterior; after 70°C exposure, it can recover when cooled.
The finding could broaden scientific understanding of complex life’s thermal limits, affecting researchers in biology, genetics, and astrobiology. It may guide searches for life in hot terrestrial and extraterrestrial environments. Biotechnology could eventually benefit if heat-tolerant cellular mechanisms inspire new tools, though such applications remain speculative. Society may feel indirect effects through science education and future biotech, not immediate daily change.