When we analysed John Pickering's structures, we highlighted that his models were the result of mathematical calculations and a lot of patience as the artist didn't use any digital means to make his original pieces. Yet, while his structures are very intriguing, they aren't the only ones in which intricate and complex geometries were formed without using computational technologies.
Nature is indeed one of the best creator of surprising shapes and silhouettes and that's the reason why many architects and fashion designers are constantly fascinated by the possibilities of biomimicry.
As seen in a previous post, the spiral shape is almost ubiquitous in shelled animals such as the Nautilus pompilius, that inspired different architectural constructions, including Frank Lloyd Wright's Guggenheim Museum in New York.
The chambered seashell of the Nautilus has interested many mathematicians and scientists who have been trying to analyse its shape, wondering if the growth of its spiral obeys a pattern governed by the Golden Ratio.
Yet, when constructed from a Golden Rectangle, it becomes clearer that the Golden Spiral is not a Nautilus spiral, but it must be remembered that there is more than one way to construct a spiral with golden ratio proportions - the shell of the Nautilus shows indeed golden ratio spiral rotation at phi squared.
There are more spiralling curves to discover in shells (one of the richest institutions dedicated to shells is the Museum of Malacology in Cupra Marittima, Italy), all of them fascinating and graceful, including the ones that characterise the Lithopoma caelatum (or carved star shell), the Mikadotrochus gotoi and the Entemnotrochus rumphii (both marine gastropod mollusks from family of the Pleurotomariidae or slit snails).
The Astraea heliotropium or sunburst star turban is also fascinating for its dome-shaped spire and curved vaulted spines, while the Guildfordia yoka (both come from the family Turbinidae, or turban snails) looks more fragile with its radiating ribs.
The Angaria delphinus (from the family of the Angariidae) is instead protected by spine elements that help the mollusks not to fall into the sand. The spines, that are also slightly bent and follow the shape and silhouette of the shell, also have a defensive function.
One of the most interesting ways to study the structure of shells remains sectioning them longitudinally, to discover their internal configuration that usually reveals fascinating chambers and spaces as proved by these samples of Vasum turbinellus, Tibia curta, Tectus sp., Tutufa bubo and Chicoreus ramosus.