When you think of tough animals you want to base your body armor on, sea sponges aren’t your first choice. After all, they’re squishy. Who wants to go up against a bullet in a sponge suit?
More people than you may think.
First, you need to understand how a bullet-proof vest works. Aramid fibers (i.e. Kevlar) help protect against bullets by distributing the force of a bullet over a larger area. If you’ve ever seen somebody in a bullet-proof vest fall over after being shot, it’s because they’ve basically just experienced the equivalent of getting whacked in the chest with a hammer.
So how do sea sponges manage to improve that? Their skeletons are made up of elements called spicules. Spicules are hard and lightweight, but so flexible they’re difficult to cut, inspiring manmade versions that are even more flexible. So if you take a bullet with a vest using these, they bend, absorbing the kinect energy of the bullet, and hopefully flicking it away when they unbend, because that’d be awesome.
Scientists are currently working on building body armor out of these. Personally, we just kinda want to see a trampoline covered in these things.
Scientists Inspired By Sponges Invent New Material [Johannes Gutenberg University]