How are shells made?
Summary
Prompted by a listener’s curiosity, this episode explores the science behind seashells, visiting the Natural History Museum to meet the diverse mollusks that create them. The show explains how these animals build durable shells using calcium carbonate and how mathematicians have decoded the geometric rules governing their intricate spiral shapes. It also investigates the biological functions of shell colors and patterns, revealing that features like iridescence often serve to strengthen the structure or aid in predator avoidance rather than just aesthetic appeal.
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