The mussels’ beards (which cooks remove before preparing them) are made up of byssal threads and are used to help keep the mussels tethered in place. At the end of each thread is a disc-shaped ...

In the first part of the video, you see a marine mussel producing the byssal threads and glue plaques it uses to anchor itself to rocks and other mussels in the intertidal zones where it lives.