Algae do not merely grow onrocks, they also grow in the cracks and crevices of rocks making the seaweed organisms a difficult meal for consumers such as Cryptochiton stelleri, otherwise known as gumboot chiton, a marine mollusk off the coast of California. This tenacious chiton solves the problem by grinding down rocks with an amazing set of teeth which contain the hardest known biomineral, magnetite. The outer shell of the chiton’s teeth, as professor David Kisailus explains in his latest paper, develop in four distinct stages: Read more