Is a moth warm-blooded or cold-blooded? If you google this, some would tell you it is cold-blooded. They are not completely right. This infrared study shows how a moth warms up before it flies. So at least a moth is warm-blooded when it moves.

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The moth (see the close-up photo above–what species is it?) was kept in a jar. The first IR image shows that when it was idle (sleeping?), its body temperature agreed with the ambient temperature. This means that it does not lose heat to the environment–a clever way for saving energy.

However, before making a move, it needs to heat up its flight muscles (near its head where the wings are attached) to above 30 degrees Celsius. In this observation, the warming process took 1-2 minutes for the moth in our experiment, as is shown by the sequence of the IR images. (Note: You may only observe this effect when the moth is energetic. A moth on the verge of death does not have enough energy to warm up.)

Note that we used the automatic color remapping, i.e., the heat map is rescaled based on the lowest and highest temperatures detected in the view. As a result, while the moth warmed up and appeared redder in the IR view, the background–in contrast–became bluer in the IR view. This, however, does not mean that the temperature of the background has decreased. The automatic remapping could create some confusion, but it is necessary in many cases, especially when you don’t know what to expect. It maximizes the difference by increasing the contrast and, therefore, allows the observer to pick up small changes.

The last image shows that the temperature was ready and the moth started to move. In this particular experiment, the moth responded slowly because it could have been exhausted as it had struggled quite a bit before it was imaged.

What interests me in this experiment is thermogenesis: the process of heat production in organisms. What biochemical reactions are responsible for the thermogenesis in moths and bees? Can we learn from them to find a green way to heat our homes?