Baleen, found in the mouths of some whales, is a filter-feeding system used to separate krill (whale food source) from sea water. It’s made from keratin, a substance also found in human fingernails.
Before the prominence of plastic and fiberglass, baleen was used by humans to make baskets, backscratchers, umbrella ribs, and cable-backed bows.
The word, first used in the 14th century, comes from the Latin “balaena” and the Greek “phalaina”, which translate as “whale”.
