Why do some birds fly and others don t?

Although flying brings great convenience to the life of birds, flying is also very physically demanding, so once the survival pressure of birds is reduced, they are easy to "lazy" and do not want to fly. From the known fossil record, as early as the late Cretaceous, some birds that lost their ability to fly appeared already. It was only in the Cenozoic Era, 65 million years later, when the traditional dinosaurs completely disappeared, that many huge birds appeared on the earth and completely lost their ability to fly.

50 million 40 million years ago, birds were the most powerful carnivores on land at that time. During this period, large mammals mostly ate plants, and meat-eating mammals were too small compared to these large birds. At that time, the birds that dominated the land generally had extremely vestigial wings and were incapable of flight, but they had well-developed legs, were able to hunt down prey quickly, and usually had large heads and terrible beaks.

Most of these terrifying bird fossils have been found in Europe and the Americas, such as the Gaston bird. However, since the 80s of the 20th century, the fossilized skeleton of a large carnivorous bird has also been unearthed in Henan, China. Scientists named it the Central Plains Bird according to its origin, and the age is about 50 million years ago.

This means that there used to be some ferocious large birds roaming the land of ancient China.

However, flightless birds are not all fierce predators, and some giant birds are actually very gentle. Flying and not being able to fly is actually an adaptation, but one thing seems to be certain, once the bird's flight organs have deteriorated, it is impossible to fly again.

Because some birds can fly, it has been trained in nature by nature, while some birds cannot fly because they are artificially fed and have lost the ability to fly.

The flight organs of birds are different, they mainly have wings and feathers that become from the forelimbs, and the real flight function in the feathers is the flight feathers and tail feathers, the flight feathers are grown on the wings, and the tail feathers are long on the tail.

This feather is composed of many slender feather branches, each of which is densely packed with rows of feather branches, and there are hooks on the feather branches, which are hooked together to form feathers, which fan the air and make the birds fly into the air.

There are some birds that can fly, but there are some birds that can't, which is the reason for evolution, in order to adapt to different living environments.

Well, the reason why some can fly and some can't be parallel is because their wings are different, and their words are different in the environment in which they grow, well, that's what the theory of biological evolution says.

Every bird lives in a different way, if all of them can fly, it will definitely be because other large birds choose other birds as food, while small birds have nowhere to escape and will become extinct, and their way of life is the most beneficial for themselves.

Because the species of birds are different, and the acquired growth environment is also different, like the more common chickens, in fact, they also belong to birds, just because of long-term breeding, chickens have almost lost the ability to fly.

My bird can fly because its wings are relatively large and can move its body, but some birds can't because its weight is uncoordinated and its wings can't move its fat body.

As a result of survival adaptation, some functions have evolved and some have degenerated.

In addition to the bird with the word chicken can't fly, there are also penguins can't fly, maybe most people don't know that penguins are also birds, but in fact it does, but the fact that it can't fly is easy to figure out, just its clumsy body and heavy steps, if it can fly, there will be ghosts. <>

Penguins are the least like birds, they have wings, but their wings are short and strong, and the bodies of the birds that can fly are soft, and if you look closely, the higher the birds usually fly, the longer their wings, such as eagles, so it is normal for penguins not to fly, what you can see is that they flutter on the water with their bulky wings. Penguins can't fly in fact, to some extent, it also reflects the theory of "survival of the fittest" in evolution, their living environment and natural enemies, as well as the prey they catch, are really vast and misty on the ice and in the deep sea, their food is not in the sky, and over time, their wings will naturally degenerate, becoming such a thick form, the little fat in their bodies has begun to accumulate because of the climate, just this weight, think about how big wings can support them to fly. <>

More surprising than cockroaches can fly is that kiwi birds can't fly, kiwi birds are the national bird of New Zealand, their body is very small, their beaks are long, the appearance is simple and cute, generally speaking, it is impossible for birds with relatively small bodies to fly without splitting rent, but what people didn't expect is that kiwi birds look like birds, but do not do bird things. <>

It should be noted that although they are small and look very much like birds, they have no wings, and their strength is still very small, basically there is no resistance, they will only run away when they encounter natural enemies, and their legs are still slow. The reason why they can't fly is also because of evolution, their sense of smell is very sensitive, they can easily eat insects in the soil, since they can get food so easily, so why evolve wings, and naturally they will be abolished.

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Evolutionary results adapted to production conditions. Because people can make clothes, most of the hair on their bodies has degenerated.