How Does the Mussel Grow its Beard? | Deep Look

Mussels create byssal threads, known as the mussel’s “beard,“ to attach themselves both to rocks and to each other. They use their sensitive foot to mold the threads from scratch and apply a waterproof adhesive that makes superglue jealous. SUBSCRIBE to Deep Look! DEEP LOOK is an ultra-HD (4K) short video series created by KQED San Francisco and presented by PBS Digital Studios. See the unseen at the very edge of our visible world. Explore big scientific mysteries by going incredibly small. --- A day at the beach isn’t all it’s cracked up to be for mussels that make their home along the rough and tumble California coast. To keep from being swept away by the pummeling waves, they grow 50-100 strings called byssal fibers to attach themselves to the rocks and each other. Those fibers are collectively called the byssus, otherwise known as the mussel’s “beard.” So, how does the mussel create the byssal threads? Turns out mussels have a thread-making factory in their foot. The foot, which looks like a little tongue, has a groove that runs its length. “The mussel squirts protein building blocks, which are liquid, into the groove channel. Then they become solid in just a matter of minutes,” says Matthew Harrington, a researcher at McGill University who takes inspiration from nature to create better and more sustainable materials. The waterproof glue that the mussel uses to attach each thread to the rock hardens in water. Having a glue like that would be very useful for humans, especially in medical and dental situations where the adhesive needs to stick in a wet environment. “If you’ve tried to put a piece of tape or glue onto a wet surface, even a slightly damp surface, you know it doesn’t stick,” says Harrington. “But mussels figured out how to glue things to a wet surface. It’s really interesting how they solved a problem that we, as engineers, have been working on for over 100 years.” --- What do mussels eat? Mussels are filter feeders. They suck in water, and they filter out tiny bits of food like algae and detritus churned up by waves. --- What are mussels made of? Mussels build their shells out of calcium carbonate, which they pull from the water. --- How do mussels attach to rocks? Mussels use their byssal threads, or “beards,” to connect themselves to rocks. In addition to their strong shell, keeping themselves attached to a rock makes it harder for predators to attack them. --- Find additional resources and a transcript on KQED Science: --- For more information: Harrington Lab at McGill University studies how mussels make byssal threads to create better and more sustainable materials: Messersmith Research Lab studies the glue that mussels use to connect to rocks, in order to create adhesives for humans to use in situations like surgery, where the adhesive needs to harden in a wet environment: --- More Great Deep Look episodes: Barnacles Go to Unbelievable Lengths to Hook Up | Deep Look These Feisty Hermit Crabs Brawl Over Snail Shells | Deep Look Ever Seen a Starfish Gallop? | Deep Look --- Shoutout! 🏆Congratulations🏆 to these fans on our Deep Look Community Tab who correctly answered our GIF challenge! Scatman John Edison Lewis Cordon Grouch MegaPiglatin --- Thank you to our Top Patreon Supporters ($10 per month)! Burt Humburg Karen Reynolds Daisuke Goto Companion Cube David Deshpande Chris B Emrick Tianxing Wang Wade Tregaskis Mark Jobes Blanca Vides Kevin Judge monoirre Laurel Przybylski Cindy McGill Titania Juang Roberta K Wright Supernovabetty KW Rory B. Syniurge El Samuels Jellyman Mehdi Jessica Hiraoka Cristen Rasmussen Carrie Mukaida Kelly Hong SueEllen McCann Noreen Herrington Laurel Przybylski Nicolette Ray Caitlin McDonough Elizabeth Ann Ditz Levi Cai Delphine Tseng Louis O’Neill TierZoo Jeremiah Sullivan --- Follow Deep Look and KQED Science on social: @deeplookofficial Instagram: Twitter: --- About KQED KQED, an NPR and PBS affiliate in San Francisco, California, serves Northern California and beyond with a public-supported alternative to commercial TV, radio and web media. Funding for Deep Look is provided in part by PBS Digital Studios and the members of KQED. #musselbeard #byssalthread #deeplook