Insect thermoregulation

In order for an animal to fly, its flight muscles need to be capable of high mechanical power output, which in turn, due to biochemical inefficiencies, end up producing large amounts of heat.

[3] A flying insect produces heat, which, as long as it does not exceed an upper lethal limit, will be tolerated.

[4] This is probably caused by the flight muscles working at higher levels and consequently, increasing thoracic heat generation.

The first evidence for insect thermoregulation in flight came from experiments in moths demonstrating that dissipation of heat occurs via hemolymph movement from the thorax to the abdomen.

[6] Then, it was then suggested that thermal stability in honeybees, and probably many other heterothermic insects, was primarily attained by varying heat production.

[3] Thus, the rest of this chemical energy is transformed into heat that in turn produces body temperatures significantly greater than those of the ambient.

So, heterothermic insects have adapted to make use of the excess heat produced by flight muscles to increase their thoracic temperature pre-flight.

The pre-flight warm-up behavior of male moths (Helicoverpa zea) has been shown to be affected by olfactory information.

The Japanese honeybee (Apis cerana japonica) is preyed upon by a hornet (Vespa simillima xanthoptera) that usually waits at the entrance of their hive.

The liquid of the drop evaporates dissipating the excess of heat in their bodies consequence of the rapid ingestion of relatively high amounts of blood much warmer than the insect itself.

[18] In cool climates, darker coloration allows males to reach warmer temperatures faster, which increases locomotor ability and decreases mate search time.