A new Technion study looks at how marine organisms produce hard tissues from the materials available to them, and under harsh and hostile conditions.
An international research group led by the Technion – Israel Institute of Technology has recently deciphered the process through which marine organisms develop their hard and durable skeletons.
The wonders of underwater engineering
The study, led by Prof. Boaz Pokroy, doctoral student Nuphar Bianco-Stein and researcher Dr. Alex Kartsman from the Technion Faculty of Materials Science and Engineering conducted the study with the assistance of Dr. Catherine Dejoie from the European Synchrotron Radiation Facility (ESRF) in Grenoble, France. The results were published in the Proceedings of the National Academy of Sciences in the US.
The researchers focused their efforts on the involvement of magnesium-containing calcite in the biomineralization process – the process by which living organisms produce minerals to harden or stiffen existing tissues. Calcite is a common mineral that constitutes about 4% of the mass of the Earth’s crust.
“Biomineralization processes build structures that surpass artificial products of engineering processes in many aspects, such as strength and resistance to fractures,” Pokroy said.
What can we learn from the starfish?
The researchers found that the deposits of calcite particles in magnesium-poor substances create compression in the organisms’ skeletons that increase their rigidity. This occurs naturally, without the need for mechanical compression used in the production of similar materials in classical synthetic engineering processes.
“We have discovered that this phenomenon occurs in a huge variety of creatures, even creatures from different kingdoms in the animal world, and we estimate that it is even broader than what we have discovered,” Pokroy said. “Therefore, it is likely to be a very general phenomenon.”
The study was supported by an EU grant from the European Research Council.
Nine different organisms were examined, including brittle stars, red algae, starfish, coral and sea urchins. In brittle stars, the crystallization process is used for its calcite lenses, which essentially function as eyes scattered all over their arms.
Red algae, however, use the magnesium-calcite crystals to coat all their cells and increase durability as the algae are subjected to the pressures and physical trauma of shallow waters.
“There is no doubt,” Pokroy concluded, “that we have a lot to learn from these biological processes, and that our findings may lead to improved engineering processes in a variety of areas.”