It’s easy for bees to get all hot and bothered. Flying takes a lot of work! To flex those wing muscles, bees convert chemical energy to mechanical work.
Insect flight can require metabolic rates up to 500x resting rates, so a lot of heat can be produced very quickly. To keep from feeling the burn, bees can do a few cool things to beat the heat.
- They mouth off.
Honeybees regurgitate nectar and spread it over the long surface of their tongues, extending it over and over. This behavior, called tongue-lashing, increases evaporative heat loss – similar to dogs panting.
2. They go against the flow.
Some species of bumblebees and carpenter bees have a loop that circulates hemolymph (bug blood) from the thorax to the abdomen and back. At high temperatures, these bees can alternate the flow so that it only goes in one direction at a time. This allows hot hemolymph from the thorax to be cooled by the wind across the large abdominal surface; then the flow to the thorax is turned back on and all that cooled hemolymph goes to the flight muscles.
- They let it go to their heads. Some species of carpenter bees will direct super-heated blood to their broad, flat heads; when the wind contacts the large surface, it blows lots of the heat away.
That’s not all! Some studies on pallid bees, orchid bees, and honeybees suggest they might be able to reduce their metabolic heat production by decreasing how frequently they beat their wings. Now that’s some sweet motor control!
Written by Meghan Barrett and illustrated by Clayton McIntosh.
Barrett is currently a Biology PhD student at Drexel University, studying an expanded version of “bug brains.” When not fawning over native bees as part of her ‘Bee Bytes’ initiative (byte-sized introductions to the bees of the US), she spends her time writing ecological poetry and science plays (or dabbling in #scicomm). More about her work can be found at meghan-barrett.com; you can find her on Twitter (@Bee_Bytes).
McIntosh (a.k.a. Domestic Cowboy) lives in Brisbane, Australia, where he creates and illustrates resources for children. You can check out his latest project, Mount Triange, at mounttriangle.com or follow him on Instagram @domesticcowboy.
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