The impressively strong appendage mussels use to attach themselves to rocks could aid in medical advances for bone and tendon repair.
Researchers have been studying mussel's byssus threads, which are "fine filaments" resembling bungee cords, The Telegraph reported.
The threads are composed of 80 percent stiff filaments on one end and 20 percent softer and more pliable material on the other.
The material is made from protein related to collagen, a substance that makes up bones, tendons, and cartilage.
This unique material allows the byssus threads to be pulled on and deformed by the rough ocean without breaking or detaching from the rock.
"This combination works like a well-designed bungee cord, which can stop the fall of a person jumping from a great height - and do so gently enough to prevent injury, because the stiffer region of the cord slows down the fall, but the softer region tempers the slowing of the fall to be a gradual process," Zhao Qin, a civil and environmental engineer at the Massachusetts Institute of Technology, said. "These findings could help in the design of synthetic materials that share some of these properties.
The researchers placed an underwater cage in the Boston Harbor for three weeks to allow mussels to attach themselves to the object, an MIT press release reported.
The sticky substance found on the appendage is not strong enough to withstand the force of the waves so the team had to look for another answer.
"We figured there must be something else going on," Markus Buehler, who heads MIT's Department of Civil and Environmental Engineering, said. "The adhesive is strong, but it's not sufficient."
After studying computer simulations, the researchers concluded the 80-20 ratio of stiff and soft material had the lowest reaction force, and could be responsible for the thread's unusual strength.
"Having more of the softer material increases the reaction force because the material cannot effectively slow down deformation. Moreover, having more stiff material in byssus threads has other advantages, as it prevents the mussels from being pulled too far out by waves, which 'would make it easier to hit other objects' and be damaged", Qin said, according to the press release.
Material from the threads could be recreated synthetically to engineer new medical glue, The Telegraph reported.
Glues created from the collagen-like-substance may be helpful in the repair of injured bones and tendons. Sticky threads could also be created to be used in blood vessel sutures.
The newly-understood material could also be used to attach instruments to buildings, and in underwater vehicles or sensing equipment, the press release reported.
"[This is] a stunning result. Like the rest of the field, I certainly never suspected an architectural feature of the byssi themselves to be so central to the dynamic resilience of these organisms ... the magic of this organism lies in the structurally clever integration of this compliant region with the stiff region," Guy Genin, a professor of mechanical engineering and materials science at Washington University, said.
