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In page Ambergris:

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Ambergris is formed from a secretion of the bile duct in the intestines of the sperm whale, and can be found floating on the sea or washed up on coastlines. It is sometimes found in the abdomens of dead sperm whales.[1] Because the beaks of giant squids have been discovered within lumps of ambergris, scientists have hypothesized that the substance is produced by the whale's gastrointestinal tract to ease the passage of hard, sharp objects that it may have eaten.[citation needed]