Nothing but Blue Skies

Seashells are exoskeletons, plain and simple. When molluscs of the crab/mussel/oyster variety are born, they are pretty much gooey little blobs that emerge from eggs. However, an evolutionary quirk of theirs is a high level of dissolved calcium in their blood. As they grow, the calcium precipitates out of the blood and out of their body onto their skin, where it will then react with other bits of stuff (usually sand or bits of rocks) to form calcified compounds. The many different colours and shapes created depend on what sort of compound is created, be it calcium oxide, phosphate, chloride, or whatever it is. So shells = bones, really. Just on the outside. And once the creature dies, shells get recycled and stolen by other creatures; hermit crabs are a notable example.

:3

Well I hope you enjoy your light fluffy clouds, here in Borington the sun is streaming down at frighteningly high levels. I wonder if we were all transported to Midnight at some point (have you got their yet sasha? The bus?) because the light is strong. Painfully strong. As in, I-can-barely-see-and-the-reflections-off-stuff-burns-my-retinas.