Starfish, also called Asteroidea, are marine animals that have a radial morphology and a calcareous ossicle composed of jointed parts. In a recent study, researchers indicated that some of these starfish composed of a very fragile mineral are fortified by means of architectural techniques. The mineral concerned would be called calcite.
In fact, according to the researchers, the skeleton of a starfish is made up of pebbly growths called ossicles which mainly consist of the mineral calcite. The latter is very fragile, even more so when it is porous. However, the starfish’s hole-riddled ossicles are enhanced by an unexpected arrangement.
Furthermore, the way the animal forms the diamond-shaped network remains a great mystery to scientists.
Scientists examined the ossicles of dozens of stars dead cells using an electron microscope at a distance of 50 micrometers, or about half the width of a human hair. They were able to observe that the apparently amorphous body of each ossicle gives rise to a structural pattern which reflects the arrangement of carbon atoms in a diamond lattice.
” When we first saw the structure, we were truly amazed. »
Ling Li, materials scientist at Virginia Tech in Blacksburg
A diamond shaped lattice and pattern of the mineral calcite
Also during this study, the scientists noticed that the diamond-shaped network is at the origin of the hardening of the ossicles starfish. However, it is not the only explanation for this phenomenon. This is because the atoms that make up calcite have their own pattern in this lattice, which looks like a stack of hexagons. This pattern affects the strength of calcite minerals.
In general, the mineral resistance is not equal in all respects. Thus, calcite becomes more brittle when pressure is exerted on it in one direction rather than another. In addition, the atomic structure and the diamond-shaped lattice are arranged in the skeleton to compensate for the natural weakness of calcite.
Furthermore, by understanding how starfish build their skeletons, it would be possible to develop stronger porous materials.
SOURCE: SCIENCE NEWS