63°C
Observed

Culture density rose over seven days; cells in mitosis were imaged.

What it shows

Growth and cell division at this temperature.

64°C
Observed

Cells moved.

What it shows

Activity, without evidence of reproduction.

70°C
Observed

Cells formed cysts during five minutes of heat, then recovered at 60°C.

What it shows

Brief survival, without evidence of growth at 70°C.