Photo: Cyron (Flickr)
In our last Moment of Science we heard how cockroaches can survive much higher doses of radiation than humans can.
But did you know that cockroaches also have a special ability that could allow them to survive some of the consequences of global warming?
Insects breathe through small pores located along their body. These small openings, called spiracles, act like valves, and can open or close to regulate the movement of fresh air in, or exhaled breath out of the insect’s body.
When we are breathing through our nostrils or mouths, we lose water as we exhale the humid air from our respiratory system. Cockroaches have the same problem– losing water as they breathe.
Scientists have known for some time that cockroaches can hold their breath by tightly shutting their spiracles for up to forty minutes at a time.
Why Would They Do That?
Since cockroaches live underground or in small crevices, one hypothesis was that they might hold their breath because of the build-up of carbon dioxide in these small spaces. But a team of Australian biologists tested cockroach breathing patterns in different conditions, including high CO2, low CO2, as well as in high and low humidity.
They discovered that cockroaches took shorter breaths and held their spiracles closed longer in dry conditions than in humid. They didn’t breathe less often in high CO2 than in low CO2 conditions.
So The Cockroaches Can Conserve Water in Hot, Dry Conditions by Holding Their Breath?
Exactly. This trick is probably one of the ways the lowly cockroach has managed to colonize and thrive in such diverse climates and environmental conditions.
Read More: Cockroaches breathe discontinuously to reduce respiratory water loss (Journal of Experimental Biology)