The blue whale is so big because it has an innate advantage: it is in the water.

Animals on land are influenced by gravity and cannot grow wildly without restraint. If it is heavy enough, the legs can't support the body. But in the sea, it's different. The buoyancy of water counteracts some gravity, making it easy for blue whales to grow into bugs.

▲ The British Museum of Natural History exhibited the bones of 126-year-old blue whale.

The ancestors of blue whales are mammals on land. After genetic testing, its genes are the closest to those of land creatures such as hippos.

In the process of evolution, some creatures climbed onto the land, while others returned to the ocean, such as the ancestors of whales. Back in the ocean, in order to adapt to the cold water, the ancestors of whales evolved into larger bodies.

▲ Walking whales and their skeletal fossils, one of the land ancestors of whales.

As you get bigger, you need more food. This requires whales to have efficient predation ability.

Whales today can be roughly divided into two types: baleen whales and toothed whales. Baleen whales are bigger. They have no teeth in their mouths, only thick beards. Whale whiskers are the same as our hair and nails.

▲ Details of the whalebone plate of the plug whale, which can filter out food from seawater. Figure/Wikipedia

The baleen whale leans against the baleen whale, and swallowing seawater can filter the food inside. They swallow a lot of seawater in one gulp, leave food in their mouths with baleen whales, and the seawater is filtered out. This efficient and unique hunting technique makes baleen whales bigger and bigger.

Blue whales belong to baleen whales. Although it is big, its esophagus is very narrow. Not only will it not eat people, but it will choke to death on a piece of bread.

▲ On March 30th, 20 17 local time, a blue whale swam in the Indian Ocean near Sri Lanka. Figure/vision china

As we all know, big fish eat small fish, small fish eat shrimp. As the largest animal, blue whales eat very little food.

The blue whale's staple food is Antarctic krill, which is smaller than human little finger. It is not a real shrimp, but more like a distant relative of shrimp. The most special thing about it is that it glows, which helps to blur its shape and avoid predators. They live in groups and are numerous, which is the favorite source of protein in the upper food chain.

▲ krill.

However, although the blue whale is huge, it is very slim. It has a streamlined perfect body shape and can swim 20 nautical miles per hour. It is considered as a fast swimming animal in the sea. Its back is blue-gray, but it looks lighter in water.

Many cetaceans, because of their huge size and slow movement, are covered with whale lice, which makes people panic at first sight. The blue whale swims very fast, and whale lice seldom disturb it.

▲ Blue whales are preying on krill.

You may think, will the blue whale get bigger?

Unfortunately, it is unlikely. The predation method adopted by blue whales is called sudden predation. They directly enter the krill group and open their mouths to spit out seawater and food. The energy required for this process increases with the size of the predator. It is estimated that creatures that use this predation method can grow to 33 meters, which is similar to the size of blue whales today.

How big is the blue whale?

Judging from the dinosaur fossils left over from ancient times, the blue whale may be the largest animal that ever lived on earth. Because many fossils are incomplete, the accuracy of weight estimation is not high. At present, the data is relatively accurate. The largest ichthyosaur is only 20 meters long and weighs about 50 tons, which is not enough to compare with the blue whale.

Generally speaking, female blue whales are bigger than male blue whales. The largest blue whale found by people is 33.5 meters long and weighs 240 tons, but it is not credible because it is not the data obtained by official scientific research.

▲ An adult blue whale.

1938, a female blue whale was captured in the Antarctic waters, with a body length of 29.9 meters, which is longer than the basketball court and a weight of 177 tons. This is the most reliable data about the size of blue whales.

Regardless of length or weight, the blue whale leaves other creatures behind when riding. The biggest creature on land is the African elephant. A blue whale is equivalent to the weight of about 33 African elephants and 2,000 to 3,000 people.

▲ Comparison chart of blue whale and human body shape.

The blue whale has a huge body, and its tongue alone weighs 2000 kilograms. The heart is 500 kilograms, and the blood vessels are thick enough to hold a child. The total weight of blood is about 8~ 10 ton, even if it is transported by train, it needs four or five carriages.

Blue whales are distributed in the oceans of the northern and southern hemispheres from the South Pole to the North Pole, especially near the South Pole. It has at least three subspecies: northern blue whale, southern blue whale and dwarf blue whale. But despite this name, the average length of the pygmy blue whale is 20 meters.

▲ An underage blue whale and a female whale.

Whale is a huge animal. It is recorded in ancient books that "it often leaps with its head in the sea and hangs on the huge waves of Hongbo, like a somersault, with its head and tail spinning on the water." Or a hundred groups, the former shark (the name of the ancient whale) turns over, and the later shark comes. The white waves are sky-high, the mountains shake, the sun and the moon are miserable, and the fishing boat looks far away, which is often frightening. "

The jumping and jumping of whales is one of the most spectacular sights on earth. The whale jumped out of the sea with its head held high, jumped over an invisible horizontal pole like a fosbury flop, and finally slapped the sea with its back, causing a huge wave and a thunderous noise.

▲ The big-winged whale jumps and waves.

Whales may jump and hit the waves to stay healthy. At present, scientists speculate that surfing may be a way of communication between relatives and friends, or it may be a pure pastime.