Photo of the Day

The mineral component of bone is comprised mostly of the calcium phosphate mineral hydroxyapatite which is embedded in the organic component type I collagen. When bone is exposed to a mildly acid environment the mineral component leaches out leaving only the pliable organic component. Vinegar is safe to use and does not destroy the protein scaffolding that gives bone it’s characteristic shape. This is a human fibula tied in a knot.

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Photo of the Day

a Risso’s Dolphin, photographed in Monterey Bay, California. These scars are assumed to be from the teeth of other Risso’s dolphins (called rake marks) and from the squid that they eat which have sharp hooks on their tentacles. Eventually, the Risso’s dolphin can be almost completely white. The amount of white scarring generally increases with age and older individuals can have a notably white head because of this. These scars, along with unique features on the dorsal fin allow for identification of individual dolphins, although allowance has to be made for them changing over time.

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