How do whales reproduce?
Whales are very different from ordinary fish. Ordinary whales lay eggs, but whales are not, so how do whales reproduce?
How do whales reproduce?
Whales reproduce through viviparity. The reproductive cycle of whales is 2-3 years, and the gestation period is 11 and a half months, which is more than that in winter. For each birth, the length of the newborn whale is about 5 meters. The lactation period is 7 months and the life span is about 50 years.
Second, the characteristics of whales
The common characteristic of cetaceans is that their body temperature is constant, about 34 ℃-36.5℃. The skin is exposed, the body hair is degenerated, and there are only a few bristles on the snout, no sweat glands and sebaceous glands. The fat under the skin is very thick, which can maintain body temperature and reduce the body's specific gravity in the water. The skull is well developed, but the brain is small, the face is large, and the prefrontal bone and maxilla are significantly lengthened, forming a long snout. The neck is not obvious, the cervical vertebra is healed, and the head is directly connected to the torso. Their eyes are very small, without lacrimal glands and nictitating membrane, and their eyesight is poor. There is no outer ear shell, the external ear canal is also very thin, but the hearing is very sensitive, and can sense ultrasound, rely on echolocation to find food, contact companions or escape enemies.
III. Species of whales
There are many kinds of whales, which are roughly divided into toothed whales and baleen whales. There is a very thick layer of fat under the whale's skin, commonly known as whale oil, which keeps the whale warm and stores energy for emergencies. Because the whale has many special structures that enable it to breathe in the water for a long time and slow down its heartbeat, when it sank to the bottom of the sea, it will take a long time before it will surface again. In addition to having the structure to store oxygen, when a certain part of the body needs a large amount of blood supply, the body will also have a special function of centralized supply.
Whales are marine mammals and protected animals, which can only be seen on television or in aquariums.
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