Ask the researchers

Ask the researchers

Why don’t ants die when they are placed in a microwave oven? (Melissa V. Queiroz, via Facebook)

daniel buenoMicrowaves are very high frequency electromagnetic waves. They cause water molecules to vibrate and this is what heats food. If the plate is dry, its temperature does not change. Likewise, if the ants have little water in their bodies they get out unscathed. A human being, on the other hand, would not get off as lightly as these insects if put in a super-large microwave oven: the water, which accounts for 70% of our bodies, would heat up. Low intensity microwaves, however, are everywhere, coming from cell phones, but there is no proof that they cause problems for humans.
Emico Okuno
Physics Institute 
of the University of 
São Paulo (IFUSP)

From an environmental and physiological viewpoint, the survival of ants during the heating of food is also plausible, although not necessarily because they have little water in their bodies. Native to warm environments, tropical ants can tolerate body temperatures up to 45º Celsius. Another one of their weapons is their behavior, which allows them to avoid places of greater risk. They have efficient temperature sensors and avoid very hot places. As the temperature within a microwave oven is never uniform (which is why it has a revolving plate), walking quickly may be their salvation.
Carlos Navas
Biosciences Institute of the University of 
São Paulo (IBUSP)