Why do giraffes have long necks?

Biological evolution is one-way and there is no turning back. Once a certain evolutionary route has been chosen, it must be strengthened and perfected, and it cannot be reverted back to the original state. When organisms reproduce their next generation, they will select individuals with strong bodies and good genes, which is called sexual selection.

This is also common in humans, and women mostly prefer men who are physically strong. Within a giraffe population, there is an average length of the neck in a historical period, but there are certainly higher than average and smaller than average. According to the normal distribution, both those who are longer than the average and those who are shorter than the average account for the minority, and those who are near the mean account for the vast majority.

During the feeding process, the leaves that can be reached by the average length of the giraffe must be eaten more, and the competition for food at this height will be more fierce because everyone can reach it. However, individuals who are significantly higher than the average can eat most of the leaves that cannot be eaten in the group, so that they can have more food, and they can grow stronger and healthier, becoming the most "charismatic" and competitive individuals in the population. When it comes to breeding season, female giraffes obviously prefer giraffes with strong necks, and giraffes with necks have a chance to breed more offspring.

The giraffe near the average obviously can't compete with the long-necked, while the short-necked one eats less than others and is smaller than others, and the chance of breeding is much smaller than that of other individuals. This happens again and again in every breeding season and in every generation of giraffes. As a result, the genes of long-necked giraffes account for an increasing proportion of the population, and the average value of the necks of the entire giraffe population is also being raised, which in turn strengthens this culling mechanism.

So after a considerable period of time, the giraffe's neck will grow longer and longer. Wish.

Because it has evolved over many years!

Giraffes have such long necks to survive.

The giraffe has a graceful, long neck and legs with distinctive markings on its body, which makes it instantly recognizable. Giraffes all have short horns on their heads.

Like other mammals, the giraffe's flexible neck contains only seven dorsal vertebrae, but these bones are elongated. The giraffe has a long neck, which must have been formed to adapt to the environment. The ancestors of giraffes lived in an environment without grass.

In order to survive, they have to try to stretch their necks to eat leaves, so that from generation to generation, their necks slowly become longer.

There is also a saying that there are slight differences between the ancestors of giraffes, some have long necks, some have short necks, and over time, those with long necks can eat leaves, and those with short necks starve to death. In this way, the long neck is inherited, and it becomes a giraffe.

The habits of giraffes

The giraffe has a pair of large brown eyes, prominent eyeballs, can rotate around, has a wide field of vision, and has a tall body, like a living "lookout", can see movement in the distance. Giraffes run fast because of their long legs, which is also trained in the competition for survival. When running, the posture is very special, first stretching the head and neck, and then retracting again, alternating swings.

The four-legged walking style is different from that of other beasts, in that the two legs on the same side and the two legs on the other side alternately move forward, jumping forward. Running fast. Tall and long legs, limbs can be kicked in front and back, left and right, all He Lu stupid directions, wide range of hits, great power, if the adult lion is unfortunately kicked, can immediately break the leg and break the waist.

Giraffes walk with a leisurely gait. When walking, one front and rear limb moves forward and the other front and rear limb touches the ground. This is a common locomotion used by large quadrupeds, such as elephants.

On Sunday morning, the sky was blue and sunny. With such good weather, Xiaodao decided to go to the zoo.

Xiaodao and his mother came to the zoo with a camera, and they saw the bustling crowd, what a big zoo! And lots of cute little animals. Mom asked Xiaodao: Go to ** to play first, Xiaodao said: I want to see the giraffe. Empty.

Mom came to the giraffe hall with a trail, and the giraffe's neck is so long! Mom said that giraffes are the tallest animals in the world. He has a long neck, four legs that are neither long nor short, a pointed mouth, two small ears on his head, and two short horns next to the ears, and likes to wear clothes full of brown and white markings.

Soon it was getting dark, and my mom and I reluctantly left the zoo.