The origin of common names
In English, members of the Rorqal family are generally called "Rorqal", which is a name derived from Norwegian and originally meant "Plough Whale". This is because they have one thing in common: from the mandible to the navel, there are many long sulcus folds, called laryngeal sulcus or abdominal folds, whose main function is to assist eating. Gray whales belonging to the suborder baleen whales, and some beaked whales belonging to the suborder toothed whales, also have structures similar to throat and abdominal folds, but the former has only four simple folds, which are far less than dozens to nearly a hundred of baleen whales in number; The so-called "throat fold" of the beaked whale is just a V-shaped groove on each side of the cheek.
Whale
Minke whales are often called "minke whales" in English. The origin of this name may be related to Norwegian or German whaling gunner Meincke. It is said that in a whaling operation in the early 20th century, he mistakenly killed minke whales as blue whales. Another way of saying it is that the whaling crew thought they were too small to catch, and "minke whales" was a joke he blurted out at that time.
Be distributed
Baleen whales are widely distributed in the waters around the world. Blue whales, fin whales, humpback whales, plug whales and minke whales may be found in all oceans, but Brucella whales are special. They don't seem to appear in the cold waters around the North Pole or South Pole, but stay in the warm tropical regions all the year round. Most baleen whales of the baleen family live in the ocean and are rarely near the coast. The only exceptions are Brucella and Megaptera: the former is usually found near the coast all year round, while the latter is often close to the coast during the annual migration from north to south.
Only the largest and smallest species in the baleen whale family-blue whales and minke whales-will swim to the cold waters at the southern tip of Antarctica. Fin whales usually don't go near the Antarctic ice shelf, while right whales range farther north. (Because of the large land area in the northern hemisphere, it has a strong influence on climate and ocean currents, and the above situation is not obvious. No matter what kind of baleen whales are, generally speaking, larger individuals tend to be close to the polar regions, while younger whales mostly stay in the south (or north).
move
Most baleen whales breed in warm tropical waters in winter, and feed on plankton and krill in summer, so they migrate long distances from north to south every year. Brucella whales are the only exception in the baleen whale family. There seems to be no obvious division between feeding period and breeding period, and some populations may not even migrate.
Feeding mode
The feeding habits of various baleen whales are different. For example, blue whales only feed on krill, while Brucella whales mainly feed on small fish. The feeding behavior of baleen whales is sometimes described as "gulper" because their feeding way is to swallow a large amount of seawater at a time with their mouths open. At this time, they will expand their throats and abdomen to increase the volume of their mouths, and then close their mouths to spit out the water, so that the food contained in the seawater will be blocked by baleen whales and left in their mouths.
In the world, baleen whales are divided into three families, namely, Right Whale Family, Gray Whale Family and Fin Whale Family, about 6 genera, 1 1 species.
Baleen whales are huge, and the smallest species is more than 6 meters long. There are no teeth in the mouth, and only degenerated teeth can be seen during embryonic development, but there are 150-400 comb-like horny whiskers on the maxilla from the palate to the left and right sides of the pharynx. The color, shape and quantity of beards vary from species to species, which is one of the important basis for classification. There are two external nostrils, located on the top of the head, which can eject two water columns when breathing. The skull is extremely large, and some species can reach 1/3 of the body length, which is symmetrical. Healing or separation of cervical vertebrae. The sternum is small, only 1? /FONT & gt； Two pairs of ribs are connected to the sternum, and the chest cavity is incomplete. No collarbone. Flippers usually have four fingers. There is a cecum in the digestive tract. They mainly feed on small crustaceans such as krill, and some species also eat small groups of fish, as well as benthic fish and shellfish.
There are not many kinds of baleen whales. There are 9 species found in China, and blue whales, fin whales, right whales and gray whales are all found in China.