Chuck, sorry to disappoint you. It would have been a lot more dramatic, that's for sure. I'd guess that the reason a real piranha was not used in the experiment was most likely because of the danger and hassle involved with handling a real piranha. I wouldn't want to tangle with one of those, even if sedated.
In some ways, we look to nature because -- well, where else are you going to look. In recent years, however, I've seen there is a more deliberate look to nature for innovation. This is even true in the pharma industry. They're looking to nature for medicinal drugs. For one thing, drugs occurring in nature don't have to go through the same multi-year qualification process.
Current military body armor uses a kevlar layer and a ceramic plate to provide protection against high powered rifle bullets. The kevlar is a woven fabric built up in layers at angles. The ceramic plate is added to provide protection from rifle bullets. Seems like that part of the armor is already being used. The overlapping scale idea is interesting. This might hold promise for lighter, stronger armor.
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