Some cetaceans, such as dolphins, sperm whales or porpoises, have teeth, which they use to hold their prey. On the contrary, in the suborder of the mysticetes or baleen whales, those only appear in the embryonic phase. Instead of teeth, these animals develop in their upper jaw a double line of horny plates with which they filter the water they accumulate in their mouths. Thus, they catch the small fish and crustaceans on which they feed.
These long and flexible tubular structures are made up of concentric layers of keratin – a filamentous protein that is also found in our nails and hair – and a bone mineral called hydroxyapatite. It is also possible to find in them traces of manganese, iron, calcium, boron and copper.
Some reach large dimensions. The baleen of the gray whale, Eschrichtius robustus , of about 15 meters and 30 tons, extends up to 50 centimeters long. Those of the Greenland whale, Balaena mysticetus , which has a huge mouth and can weigh three times as much, can measure more than 3 meters . The latter also have several hundred of them.
During the 19th and 20th centuries, hundreds of thousands of whales were caught . Not surprisingly, these living moles are a huge source of meat, fat, wax … Throughout history, their bones have been used to build tools, weapons and even housing structures in many coastal areas where the wood and stone were rare goods. In this same sense, their beards were used in great quantity in the manufacture of rods –for umbrellas and walking sticks– and in corsetry.
Image: Thesupermat / GNU / CC
