Many beach trips have been spoiled by stepping on the sharp and strong spines of sea urchins. The urchin uses those spines for moving around and protection against predators.
OLYMPUS DIGITAL CAMERA
Each spine is a single crystal of calcite. This is normally a soft and brittle mineral, but it is highly strengthened in several ways. It is a hollow tapered cylinder, which saves weight and materials without sacrificing much strength. Some magnesium ions replace calcium ions, which produce an irregularity that impedes cracks from propagating. So, any fractures are more like in glass, a non-crystalline solid, than a crystal. This fracturing absorbs energy and protects the main spherical shell (called a test) of the animal.
The spines serve as a defence against predators, hard and at the same time shock-absorbing. As a result of these properties, the spines are among the most-studied biomaterials.
Kian Barker, owner of Eco Lodge and ShakaBarker Tours has a B. SC. in Botany and Zoology, as well as a B. SC. Honours in Ichthyology and Fisheries Science. He has published numerous articles in a variety of publications on estuarine management, tourism and related ecological aspects, as well as appearing in a number of television documentaries concerning the iSimangaliso Wetland Park. Kian believes passionately in repurposing for an even more sustainable eco friendly future. He has established an eco friendly 50 Shades of Green benchmark, that will hopefully be accepted into the tourism industry as a standard to aspire to. He has adapted Eco Lodge to embrace these green living practices, that also help conserve our natural environment, animals, and resources like water and energy. He also specialises in offering a variety of eco-tourism services in the iSimangaliso Wetland Park and surrounds.
View more posts
Tourism Tails 