Big bugs idea has no legs

by Dan Westell, CBCNews.ca

More bad news for sci-fi fans. U.S. researchers have come up with additional science that squishes the idea of giant bugs.

Amazon.com has a list of 100 big bug movies, and even if some of them are clearly a stretch, the classics - Them!, Men in Black, and Starship Troopers - have established giant insects as real stars.

Of course, such bugs couldn't exist; it's a physical impossibility, as any biologist knows, and as the University of Chicago's Michael C. LaBarbera has laid out clearly. Now the U.S. government's Argonne National Laboratory, Midwestern University and Arizona State have weighed in with their own evidence.

Using x-rays, the team set out to learn whether the insect respiratory system contrains bug sizes. Sure enough, the study in the Proceedings of the National Academy of Science reports that the size of the tracheal tubes needed to carry oxygen to the legs of big bugs would be too big to fit through the bottlenecks between the body and the legs.

In the late Paleozoic, there were giant bugs, but there was more oxygen in the atmosphere; hence the tubes didn't have to be as big as they would today.

The x-rays were used to take pictures of the tubes in four different-sized beetle species, where the body mass varied by a factor of up to 1,000.

Science 1: Big bugs 0.