The military is a dangerous calling. But technology can help out, so researchers are constantly trying to make soldiers safer. Writer Mary Roach investigates how scientists studying so-called human factors are protecting troops from such aggressive foes as heat, noise, and fatigue. She also learns how bad odors were once considered a secret weapon.And while soldiers have long used camouflage to help them blend in, insects may be the original masters of disguise. A discovery in fossilized amber shows that a variety of bugs employed D.I.Y. camouflaging tricks 100 million years ago.But where is the defense race headed? The top-secret branch of the Pentagon whose job is to make tomorrow happen today has some ideas. A reporter shares DARPA’s plan for augmented super-soldiers.Plus, do we always need a technological boost to stay safe? Find out how your innate chemical defense system protects you. It’s an adrenaline rush!Guests: Mary Roach  - Science reporter, author of “Grunt: The Curious Science of Humans at War” Michael Engel – Entomologist, invertebrate paleontologist, University of Kansas, and senior curator of its Natural History Museum Annie Jacobsen – Journalist, author of The Pentagon’s Brain: An Uncensored History of DARPA, America’s Top-Secret Military Research Agency Brian Hoffman – Professor of medicine, Harvard Medical School, author of Adrenaline Learn more about your ad choices. Visit megaphone.fm/adchoices