Crash helmets that stink. I’m Bob Hirshon and this is Science Update.
To protect your head properly, a cycling helmet has to be completely free from cracks—even hidden ones. But how can you tell? Well, German researchers have incorporated microcapsules filled with a smelly substance into a helmet’s structure. If cracks develop, the microcapsules release the compound, and you can smell that the helmet isn’t safe. And, since the smell if pretty foul, you won’t be tempted to ignore the warning and wear the helmet anyway.
In other apparel news, archaeologists working in Armenia have found the world’s oldest pair of shoes, dating back to 3500 BC. Each shoe was molded from a single piece of leather, and stuffed with grass—either for insulation, or to help the shoe keep its shape. The shoes are 400 years older than Stonehenge and a thousand years older the Great Pyramid of Giza. I’m Bob Hirshon for AAAS, the Science Society.