Scientists from the Field Museum and Argonne National Laboratory in Chicago and from Clemson University used a powerful x-ray imaging device to get the first comprehensive view of live insects breathing. Their observations and research results are reported in the Jan. 24 issue of Science, an internationally respected research publication.
"The discovery of this fundamental aspect of respiratory biology for insects could revolutionize the field of insect physiology," said lead author Mark Westneat, associate curator of zoology at the Field Museum.
Researchers discovered that many insects, including crickets, wood beetles and carpenter ants, are able to breathe using a mechanism similar to the one we use to ventilate our own lungs. This is remarkable because insects do not have lungs, but rather a system of internal tubes called tracheae, which they use to breathe through slow, passive means.
The study showed that some insects also breathe by compressing and expanding tracheae in their head and thorax, using them like lungs. The breathing cycles can be as fast as one per second, producing air exchange rates of nearly 50 percent, similar to moderately exercising humans.
"This rapid, active breathing mechanism might help to explain the tremendous success of insects, since the ability to rapidly deliver oxygen to body tissues may have played a role in the evolution of aspects of insect function, ranging from flight to the performance of sense organs, said Richard W. Blob (pronounced "Bl-oh-b"), assistant professor in Clemson University's biological sciences department.
"As we come to understand the basic physiology of animal respiration and circulation through research such as this project, we have the potential to make further discoveries that can ultimately improve our ability to treat disease in humans."
Until now, it has not been possible to see movement inside living insects. Researchers solved the problem by using a synchrotron, a circular particle accelerator that can generate x-rays. The one at Argonne National Laboratory ranks among the most powerful in the world.
"This is the first time anyone has applied this technology to create x-ray videos of living animals," says co-author Wah-Keat Lee, a physicist at the Argonne lab. "This work opens up the possibility of developing a powerful new technique for studying how living animals function."
Journal
Science