Scientists are studying the jaws of an ancient sea worm, Perinereis cultrifera, to better understand a new category of natural materials called bio-metals, according to ScienceDaily.
The worm is a predatory bristle worm that uses hard mouthparts made from structural proteins and ions to bite, crush, and eat food. Researchers say the unusual makeup and behavior of those jaws make them stand out from other biological materials that merely resemble metal.
In a study published in Biophysics Reviews by AIP Publishing, researchers from TU Wien and the University of Vienna examined the worm’s jaws through nanoindentation, chemical analysis, and imaging. Their results supported earlier findings that metal ions are more concentrated near the jaw tips than in the middle, which likely helps make the tips harder.
The team also found a size effect seen in some metals, where smaller areas are harder to dent. But they said the worm jaws also show size-dependent elasticity, a trait that helps distinguish bio-metals from standard crystalline metals such as copper or silver. The researchers say they are only beginning to understand how these natural materials work.
