Fire Amoeba Breaks Heat Record for Complex Eukaryotic Life

A newly described organism called the fire amoeba can reproduce at 145 degrees Fahrenheit and keep moving at temperatures up to 147 degrees, according to a report published by NPR on Sept. 22, 2026. Scientists say the finding marks a record for complex eukaryotic life, the broad category of organisms whose cells carry a nucleus and other internal structures — a group that includes everything from amoebas to animals and plants.

What did scientists find the fire amoeba can do?

The fire amoeba's headline trait is temperature tolerance. Researchers found it capable of reproducing at 145°F and continuing to move even as conditions climbed to 147°F, per NPR's reporting. Those numbers stand out because reproduction and locomotion require intact, functioning cellular machinery — proteins that typically break down well before water reaches such temperatures.

Why does this push the limit for complex life?

Eukaryotic cells are more structurally complicated than the simple bacterial and archaeal cells long known to survive extreme heat. Eukaryotes carry a nucleus, organelles and other internal architecture that must all keep working for the cell to divide or move. NPR's report frames the fire amoeba's tolerance as a record specifically among that more complex category of life, distinguishing it from single-celled prokaryotes that have previously dominated the list of known heat-loving organisms.

How does this compare to other heat-tolerant organisms?

The report identifies the fire amoeba's threshold — reproduction at 145°F and movement up to 147°F — as a new benchmark for eukaryotic life specifically, without listing comparative figures for other species. The distinction between prokaryotic and eukaryotic heat records is central to why scientists gave the organism its own name rather than filing it alongside previously known extremophiles.

What happens next in the research?

NPR's report documents the temperature thresholds and the significance scientists attach to them but does not detail additional experiments planned to probe how the amoeba's cells withstand heat that would denature proteins in most complex organisms. Further study of its cellular chemistry would likely be needed to explain the mechanism behind its tolerance.

Timeline

• Sept. 22, 2026 — NPR publishes the report naming and describing the fire amoeba's temperature tolerance, citing reproduction at 145°F and continued movement at 147°F as a record for complex eukaryotic life.

The full report, including additional detail on the organism's naming and classification, is available from NPR.