Natural Thermoelectric Heat Pump in Social Wasps
David J. Bergman
School of Physics and Astronomy, Raymond and Beverly Sackler Faculty of
Exact Sciences, Tel Aviv University, Tel Aviv, 69978, Israel
Photographs of wasps or hornets, taken with different temperature sensitive
infrared cameras, reveal body temperatures that are sometimes significantly
lower than the ambient temperature. This suggests that the hornets possess
an intrinsic biological heat pump mechanism which can be used to achieve
such cooling. Evidence is presented to substantiate this novel suggestion
and to argue that the heat pump is most likely implemented by exploiting
a thermoelectric effect in the hornet cuticle. Such a natural heat pump
can conceivably also serve to cool the active hornet, engaged in daytime
activities outside the nest at ambient temperatures exceeding 40 °C,
to a body temperature that is low enough to allow its survival in extreme
thermal conditions. It might also function as a means of raising the body
temperature up to a level that enables the hornet to remain active even
when the ambient temperature is as low as 10 °C.