Baleen whales (photo can be seen in the article) is one of the modern suborders of cetaceans. They impress with their size, evolutionary origin and way of life. Let's learn about the largest animals on the planet in more detail.
Order Cetaceans
This is a large group of mammals, including the largest representatives of the entire class. Now there are 38 genera, united in two suborders: baleen and toothed whales (mystacocetes and odontocetes). These are animals that are fully adapted to living in the aquatic environment. The scientific name of the detachment comes from the Greek language and means "sea monster". And this is not surprising, because whales are the largest mammals on the planet. They have a modified, streamlined, spindle-shaped body, smooth skin, and a thick layer of fat underneath. It protects animals from hypothermia. In the process of evolution, the hind limbs atrophied, and the front ones turned into giant flippers.
Baleen whales (toothless): general characteristics
The suborder includes four families, uniting 10 species. These are humpback, blue, bowhead, southern, pygmy, gray whales, fin whale, sei whale, minke whaleBride and small. Later in the article we will learn about some of them in more detail. Most representatives of the suborder are cosmopolitans and are widely distributed in the waters of the oceans. When asked how many teeth a baleen whale has, we can safely answer: none. All of them underwent significant changes in the process of evolution and turned into special horny plates. They are called "whalebone", which formed the basis for the name of the suborder. Solid formations are located across the gums one after another with an interval of 0.3-1.2 cm. The top and inner edges of each plate are split into long, thin bristles. This structure of the jaw apparatus resembles a sieve or filter. The animal swallows a large mass of water with small fish, plankton and crustaceans, and then strains it.
It was not known how many teeth a baleen whale had in ancient times, but the fact that they were is an indisputable fact. It is confirmed by the discovery of a fossil species in 2011. A small whale (up to 3 m in length) had large and sharp teeth. This proves that modern species have come a long evolutionary path to the modern structure of the elastic jaw apparatus.
Blue (or blue) whale
Only one epithet is used for this marine animal in different formulations - “the most”. The length of his body reaches 33 meters, and the weight exceeds 150 tons. This is the largest animal on modern Earth and, probably, of all that have ever lived on the planet. With such a significant size, the blue baleen whale (whose teeth have turned into a developed filtering apparatus) haspeaceful disposition and feeds exclusively on plankton. Its body is slender, elongated, with a large head, its length is 27% of the entire body. Blue whales are long-lived: according to various estimates of scientists, their average life expectancy is 40-90 years. This is a cosmopolitan species, its historical habitat covers almost all oceans. Now you can meet them extremely rarely, since at a certain period they were on the verge of complete extermination by man.
Bowhead whale
Baleen whales of this species are inhabitants of the cold waters of the Northern Hemisphere. They also have quite impressive dimensions - up to 20 meters in length (females) and 18 m (males), weight from 75 to 150 tons. They dive to great depths (up to 200 meters) and may not surface for about 40 minutes. They live on average about 40 years. The species has not been studied very well, since it is difficult to observe them in harsh climatic conditions. Feeds on plankton.
Humpback whale (long-armed minke whale)
The mammal owes its name to the shape of the dorsal fin, resembling a hump, and the characteristic habit of arching when swimming. The first photo of our review shows jumping out of the water, characteristic of a humpback. This is a fairly large whale up to 14.5 m long, less often 17-18 m, and weighing 30 tons. It differs from other minke whales in body shape and color, thanks to which it is even possible to distinguish individual individuals. The baleen humpback whale is found in all corners of the oceans, although populations are sparse. Prefers to stay in shelf and coastal zones, swims to depthonly during migrations. The species has the status of vulnerable.
Fin whale
It ranks second after the blue whale in terms of size and weight among animals (pictured above). These two species are very closely related. Sometimes there are even hybrids. Now two subspecies of fin whales are known: the North Atlantic and Antarctic, the existence of a third is allowed, according to some scientists. Individuals living in the Northern Hemisphere reach a length of 24 m in adulthood, and residents of the Southern - from 20 to 27 m. This baleen whale, unlike its relatives, willingly lives in small groups (up to 6 animals). The fin whale dives deep (up to 250 m) and swims quickly, reaching speeds of up to 50 kilometers per hour, and can spend up to 15 minutes without air under water. In addition to humans, the whale has no natural enemies. However, at the moment, the fin whale is rare and endangered.
Seival
An endangered species from the minke whale family, growing up to 20 meters in length, weighing about 30 tons. The diet is mainly made up of crustaceans and schooling fish (in particular pollock), as well as cephalopods. The baleen whale, on average, lives up to the age of 60 years. The sei whale dives well to a depth of up to three hundred meters and can do without air for up to 20 minutes. Active extermination of this species began after the number of blue whales and fin whales decreased. In 1986, fishing for it was completely banned.
Bride's minke whale
Whale of medium size, up to 14 m in length and weighing up to25 tons. It has an elongated dark gray body with small light spots (pictured). A distinctive feature is three distant growths in the upper part of the head. They prefer to live in pairs or small groups. More or less sedentary species, migrations are short-term and depend solely on the availability of food (mainly fish, cephalopods). The baleen whale is quite common in all oceans.
Toothed whales
The modern suborder includes 10 families, including dolphins, narwhals, sperm whales, porpoises, etc. A distinctive feature is the presence of teeth on the jaws. Representatives of toothed whales can be safely called predators, feeding mainly on fish, cephalopods and even other marine mammals. Almost all species are inferior in size to the previous suborder, they are mobile and excellent swimmers, with the exception of the sperm whale. It grows up to 20 m in length and weighs about 50 tons. Herd lifestyle, prefer to stay in large groups.
Another prominent representative of toothed whales is the killer whale (pictured). A cosmopolitan species, a predator with a wide range of food, but each population specializes in a certain type of fish (for example, herring in the Norwegian Sea).
