As mammals, why can whales have such a large size?

is a limiting cause of gravity and the buoyancy of water.

According to National Geographic, there is a reason why marine mammals have evolved to be huge, but not in the same way we originally thought. Terrestrial mammals can be very large, but if you're looking for a real giant on Earth, you'll have to look in the sea.

Scientists show why, in a new study. The study's lead, William Gearty, is an ecologist at Stanford UniversityAccording to him, marine mammals must find the right balance between getting enough food and generating enough body heat.

Previous researchers believedThe reason why marine mammals are so large is because the buoyancy of water frees them from the constraints of gravity. While the buoyancy of water may still be a factor, Getty says his findings show that marine mammals need large bodies to stay warm in the perennially cold oceans.

"There's a special reason why these animals are so big," he said. It's not that they can grow so big, it's that they have to grow that big.

Over the past five years, scientists have found evidence that a variety of mammals tend to evolve to larger bodies over time. Larger animals are more likely to repel their opponents when courting, foraging, and obtaining other resources, as well as a wider variety of food.

But terrestrial mammals are limited by gravity:They need a lot of bones and blood vessels to support their size and maintain their mobility, which is not easy if you weigh several tonnes like an elephant.

Gerti began his research on the factors that affect the size of marine mammalsHe had thought that only the factor of eliminating the constraints of gravity would be found. But his research data shows that the smallest aquatic mammals are 1,000 times larger than the smallest terrestrial mammals, and the largest aquatic mammals are 25 times larger than the largest terrestrial mammals, suggesting that there must be something forcing marine mammals to get bigger.

Since whales are warm-blooded, they must grow large enough so that the heat in their bodies does not quickly lose to the surrounding water. The need for thermoregulation makes the whale much larger than the Wang Xingju.

This has something to do with her own genes, their whale genes make her so big.

Because it grows very fast, it can grow so big.

Because whales are born with a huge size, this may be related to their own genes.

Because whales need such a large size to help them live.

Because they have to adapt to their body heat, they have to grow so big.

That's because there is no heaven and earth in his sea, so he would form such a large body.

Because of the need to survive, it is necessary to ensure that the reminder is huge.

This is his genetic makeup, this is a law of nature.

Be. Although the whale has the word fish, it is not a fish, but a mammal that lives in water, and has the same physiological characteristics as land mammals, such as breathing with lungs, constant body temperature, viviparity, etc., and has some special physiological structures evolved to adapt to the aquatic environment. Whales, like land mammals, are viviparous, and calves are born directly from the belly of the mother.

Why do you say whale mammals? After watching how it gives birth, everything is understood.

Although the whale lives in the ocean and swims by fins, it does not breathe with gills like fish, but with lungs like other mammals. Whales do not inhale before diving, but exhale the air in their lungs. <>

Whale. Some people believe that because a whale is big, its lungs will also be big, so that the whale can rely on its huge lungs to store oxygen and breathe underwater. But in fact, whales do not rely on their lungs to store air for breathing, and there is little or no gas exchange in the lungs.

When the whale is deeply diving, the lungs are under a lot of pressure, and the alveoli are compressed, pressing the remaining air into the large trachea, and when the exchange surface of the alveoli is completely compressed, the whale's lungs have little or no gas exchange. If the whale does not get oxygen from the lungs during the dive, it not only reduces the risk of nitrogen diffusing into the bloodstream, but also reduces the risk of small bubbles forming in the blood when ascending, so the lungs do little or no gas exchange during the whale dive.

Although whales are mammals, their body structure and physiology are not identical to those of other mammals. The blood volume and blood oxygen capacity of whales are relatively high, this is because the tidal volume of whales during ventilation is much larger than that of other mammals, the tidal volume of general mammals is only 15% of the lung capacity, while the tidal volume of whales can reach 90% of the lung capacity. When the whale is ventilated, the blood can absorb a lot of oxygen, and a large amount of oxygen will be stored in myoglobin in muscle tissue.

Due to little or no gas exchange in the lungs during diving, the amount of carbon dioxide in the whale's blood can rise to twice the usual level, and the saturation of oxygen in the arterial blood can drop to 15%. <>

Whale. The farrowing process of whales is very difficult, and newborn cubs cannot swim at all. If a calf is born with its head coming out first, it will drown in seawater on its first breath after leaving its mother.

If the calf comes out first with its tail, and when the calf is safely born, the male will immediately rush over to lift the calf out of the water and take the calf for the first breath.

Whale. At the same time, whales also need to sleep, but unlike the human sleep process, whales sleep with their bodies either sitting quietly in the water in a vertical or horizontal state, or swimming slowly next to their own kind while sleeping.

Although the distribution of whales is very wide, due to environmental factors and other factors, people have very limited research on whales. I hope that in the future, people can discover more whales and the secrets of the ocean, and uncover the mysteries of the ocean.

Although whales live in water, they are not fish, but a class of mammals. Although living in the water, some of the key characteristics of whales are the same as those of terrestrial mammals. Judging by the way they breathe, whales breathe with their lungs; Judging by body temperature, their body temperature is constant; In terms of reproduction, they reproduce in a viviparous manner, and they also have lactation.

These are the prominent features of mammals, so they are mammals, not fish.

Although whales live in water, they are a class of mammals. Compared to terrestrial mammals, their living environment is different. However, as a class of mammals, whales share some key characteristics with terrestrial mammals.

For example, in terms of breathing patterns, they breathe with their lungs, and they cannot sink deep into the water to breathe, but can only breathe with their heads out of the water on a regular basis. Judging by their body temperature, their body temperature is constant at all times. In terms of reproduction, they reproduce in a viviparous manner, and they also have lactation.

These characteristics are all prominent features of whales as mammals.

Whales live in the same environment as fish, and whales have a body shape that is so similar to that of fish, that many people think that whales are also fish. However, they are not fish, as mentioned above, they are mammals. Although their body structure is similar to that of fish, this is just a convergence over a long period of evolution.

When whales lived on land before, they didn't have a similar structure. It was only after environmental changes brought them into the water that they gradually evolved similar characteristics.

Whales are not fish because whales are very different from fish in some key characteristics. For example, fish breathe with gills and can breathe without leaving the water, but whales use their lungs to breathe like most mammals. In addition, most fish reproduce by oviparity, unlike whales, which reproduce by viviparity.

Although the whale has the word fish, it is not a fish, but a mammal that lives in the water. It has the same physiological characteristics as land mammals, such as breathing with lungs, constant body temperature, viviparity, etc., and has some special physiological structures that have evolved to adapt to the aquatic environment.

Fish lay eggs, which then turn into small fish, while whales, like land mammals, are viviparous, and calves are born directly from the belly of the mother whale and grow up on their mother's milk.

Many fish in the sea breathe with gills, while whales breathe with their lungs. Every once in a while, the whale has to come to the surface of the water to change its breath, because the whale's lungs are so big, it can breathe in the air, it can stay underwater for a long time, and then it swims to the surface, expels the exhaust gas from the lungs, inhales new air, and returns to the ocean.

Thermostatic animals refer to animals whose body temperature does not change with the change of the external environment, and the body surface coat or feathers of birds and mammals in the animal kingdom have a thermal insulation effect, and have a good structure of heat production and heat dissipation in the body, which is a homeothermic animal. Wolves, tigers, and whales are mammals, sparrows, and pigeons are birds, while snakes are reptiles, crucian carp are fish, and frogs are amphibians, and their body temperature changes with the changes in the external environment, and they belong to ectotherms.

Like all animals, whales breathe with lungs and are warm-blooded animals with their young fed by suckling and a little hair. The forelimbs of the whale form fins, the hind limbs are completely vestigial, and the tail becomes a caudal fin with nostrils in the upper part of the head. Of particular note is the blue whale.

It is the largest living animal in the world, with a body length of up to 30 meters and a weight of 180 tons. So it's mammals.

Reference: Wiki.

Whales are dairy animals.

Because whales breathe with their lungs, they are also viviparous.

For example: bats. Cat. Horse.

Sheep. Dog. Pigs and celery and so on are dairy catchers!

Reference: Myself.

Whales are mammals! ~~

Whales are mammals.

It is a mammal.

It's a mammal! Because breathing with the lungs is all tie! For example: bats, dolphins, sandfish.

Reference: Learned!

It is the first cleft mammary animal in the feeding state.

Whales are mammals! Geocities WhaleHouse88 Closed DCS Dolphinnews HK News HK News Others

It is a mammal.

Whales and whales are mammals.

Mammals Because whales you are viviparous.

Breastfeeding.

It is a mammal.

Whales are mammals. Whales can be collectively referred to as cetaceans or cetaceans, which are a taxa under the class Mammals, and have been confirmed by relevant studies that cetaceans evolved from terrestrial artodactyls about 50 million years ago, and have mammalian characteristics.

Whales have mammalian characteristics, such as reproduction, whales only produce one cub per litter, and at the same time have a long growth period, because the reproductive efficiency is not high, at present, about a quarter of the species of whales are endangered under human hunting.

Whales are currently the largest group of creatures in the world, and the largest of the cetaceans is about 239 tons, which is about 50 times the weight of the average elephant.