Unlike humans, insects do not have lungs. Their respiratory system is not coordinated to a circulatory system involving blood pumped with oxygen and delivered through out the body. Nor do they breathe though only a couple select openings like a mouth or nostrils. Instead, crickets and other insects take oxygen in via several spiracles (openings) on the sides of their bodies. (This is why crickets drown so easily if they are kept in an enclosure with a water bowl.) Oxygen enters through the spiracles and is spread through out a system of internal tubes called “tracheae”.

Until the year 2003, scientists figured that all insects exchange oxygen slowly through the tracheae tubes. Advanced technology, however, has made it possible for researchers to get an inside look at the breathing mechanisms insects. We now know that crickets, beetles, ants, roaches, and dragonflies breathe in a manner that is very similar to humans, despite the insects not having lungs.

(By the way,  did you know that crickets hear the same way as dolphins?)

A study, led by zoologist Mark Westneat, made the front cover of Science magazine because it was the first time that scientists ever watched the breathing function of living insects.  To do this, they used the help of a revolutionary piece of technology called a “synchrotron”. The synchrotron is a particle accelerator that can accelerate electrons almost to the speed of light! This makes it capable of producing x-rays incredibly more powerful than conventional sources.  Using this machine, the researchers watched live video footage of breathing crickets and discovered that the tracheae compress and expand in a similar way that human lungs compress and expand. The breathing cycles can be as fast as one cycle per second which is about the same oxygen exchange rate as a human doing moderate exercise.

Breathing X-Ray photo (BBC News)

An insect’s tracheae compressing and expanding, much like lungs.

Another cool component of the technology is the way the images can be enhanced to emphasize edges so that the outline of tracheae is clearly defined. This makes much easier for biologists to tell what is happening in the video footage and images. As you can see from the above example, the photos sort of look like penciled sketches.

“This is the first time anyone has applied this technology to study living insects,” says Wah-Keat Lee, a physicist at the Argonne National Laboratory. ~

Crickets are cooler than you thought eh?   Scientists are even making hearing aids based on crickets now!

Be sure to check out our Cricket Anatomy page for color diagrams and more facts pertaining to crickets.

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