Some species of starfish fortify themselves using a porous skeleton that is both lightweight and extremely sturdy. This provides the marine species with a safe protective home, while still permitting a degree of flexibility to their body and arms.
Taking inspiration from mother nature
Ceramic engineers have been inspired by these structures to create a new class of high-performance lightweight ceramic composites. This interesting finding is not the first time material engineers have been inspired by nature. Such as a reusable adhesive material similar to the feet of flies and a lobster-inspired hydrogel that could be used to build artificial tendons.
“Our overall goal is to learn and take inspiration from nature to develop novel porous materials,” says Ling Li from Virginia Tech who worked on the project. “Nature offers many good material lessons for designing porous materials that are both strong and damage-tolerant.”
A complex and unique structure
Starfish skeletons mostly consist of the mineral calcite. Calcite is usually fragile, though the pebbly growth-like lattice structure in which the mineral forms provides an extraordinary strength to the armor. These formations are called ossicles and are classic to the look of sea creatures. How the ossicles are structured is similar to how carbon atoms are arranged in a diamond. The group’s incredible finding was published in the journal Science.
Although similar, how calcite comes together in these formations is unique and more complex than carbon atom structures in diamonds. Leaving scientists stumped when trying to recreate the material. The team is digging deeper into understanding exactly how starfish ossicles form at a developmental level, alongside chemical and structural analysis of the skeletons. Once they have a deeper understanding of the skeletal structure, Li and his collaborators want to utilize mother nature’s incredible design.
“Nature is able to assemble mineral precursors to form complex architectures at room temperature and ambient pressure,” Li said. “That is something that modern human technology cannot currently achieve.”
A bio-inspired material of the future
He continued: “I am hopeful that this exciting research direction may one day lead to the development of a wide range of bio-inspired, stronger, and more lightweight materials.” Applications of these materials spread far and wide, including for use in modes of transport, buildings, batteries, dental fillings, and more.