Mussels have long been feted for the glue with which they adhere to surfaces in the harsh marine environment -- a cement that chemists are trying to reproduce for industrial purposes.
Just as remarkable, says a new study, is the web of the fragile-looking strands called byssus threads that the mussels use as an anchor chain.
Unlike limpets, which clamp tightly on to a surface, the hair-like filaments enable the humble bivalve to hang on loosely. This gives it a tiny ability to drift, boosting its chances of tucking into micro-nutrients in the sea.
Glue alone cannot explain why the mussel is not bashed to pieces, said Markus Buehler, a professor of civil and environment engineering at the Massachusetts Institute of Technology (MIT).
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"We figured there must be something else going on. The adhesive is strong, but it's not sufficient," he said.
He and MIT research scientist Zhao Qin analysed the byssus threads in a laboratory.
They found that the fibres, secreted by a gland in the mussel, are a remarkable mixture of proteins.
Put together, this mixture provides elasticity and rigidity, dampening the force of water but not fighting destructively against it.
The mussel is able to withstand a dynamic loading -- the sloshing about -- that is nine times greater than a static loading, meaning when it is pulled in just one direction.
The pair say that if the structure and chemistry of the byssus threads can be replicated, there are many outlets waiting for it, including anchorages for ships, submarines, wind turbines and spaceships.