Purdue speculates that mussels may only produce adhesives that are just strong enough to keep their bodies attached. A too-strong substance could actually backfire by making it difficult for a mussel to escape predators without hurting itself. The artificial version, meanwhile, is as powerful as humans want it to be.

There's still a long way to go before this glue is ready for real-world use. However, there's a good chance that could happen. The US military's Office of Naval Research funded the project, and it clearly has a vested interest in making sure that its constructions survive water. This doesn't mean that you'll see warships held together by glue instead of rivets, but the concept isn't completely far-fetched.