Biomimicry

"Teeth and bones, snail shells and bird eggs are formed via a process called biomineralization. Found across all kingdoms of life, this method of incorporating minerals like calcium or silica into hard tissues is clearly very useful in nature. The concept is so powerful that researchers are now working on applying it to the rather unnatural environment found within lithium ion batteries."

Photo by H Zell (Own work) [GFDL (http://www.gnu.org/copyleft/fdl.html) or CC BY-SA 3.0 (http://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons

""We often think of seashells as being defined by their delicate beauty. But what if they also hold the secret to producing near-impenetrable human body armor? Researchers from the Massachusetts Institute of Technology say the structure of a certain oyster shell could inspire extremely tough and lightweight exoskeletons..."

Nacre, or Mother of pearl is the iridescent lining you see on the inside of an oyster, mussel, or abalone shell. It is also the same material that creates pearls. The play of light we find so appealing is a result of the little beasties engineering the shell down to the molecular level. To create a shell that is tough and lightweight (sometimes 3000 times tougher than its component parts), the abalone layers an organic material and a non-organic material into a nano-structure design resembling brick and mortar. 

We have seen before how the abalone inspired super tough materials. Now engineering professor Nicholas Kotov and his team from the University of Michigan have created a process similar to our bivalve friends that allows the creation of materials one nano-layer at a time, with impressive results.

"..an MIT/Harvard study suggests that a specific type of limpet's shell may hold the key to transparent displays that require no internal light source. The mollusk in question is the blue-rayed limpet which, as its name implies, has bright blue stripes on its translucent shell. It is believed that these are used to make potential predators mistake it for a poisonous snail, which also has blue markings. The iridescent lines appear blue due to the fact that the shell material in those areas reflects the blue spectrum of incoming light, while absorbing other colors so that they don't drown out the blue."

A robotically woven carbon-fibre pavilion based on the lightweight shell encasing a beetle's wings and abdomen is revealed by the University of Stuttgart.

"Engineers intrigued by the toughness of mollusc shells, which are composed of brittle minerals, have found inspiration in their structure to make glass 200 times stronger than a standard pane. Counter-intuitively, the glass is strengthened by introducing a network of microscopic cracks, according to a study published in the journal Nature Communications on Tuesday."