Sparrows are birds associated with human beings. They like to live around residential areas and fields, and take the cracks of buildings as their nest sites.
Sparrows have an interesting feature, that is, they can’t walk with their feet, they can only jump, that is, they can jump and jump. I read a folk story about this phenomenon before. It said that because sparrows like to steal food, they even broke ground on Taisui’s head and stole food from the king of heaven. As a result, they were shackled by God, so they had to jump.
Sparrows are indeed ill fated. Because they often steal food in groups during the grain harvest season, after the founding of the people’s Republic of China, sparrows were listed as one of the four pests for a long time and were wanted all over the country. Gongs and drums were played everywhere in cities and villages to prevent sparrows from falling to the ground, so that many sparrows were so tired that they fell to the ground and died.
Although sparrows are no longer one of the four pests, great changes have taken place in civil buildings all over the country in recent years due to the improvement of people’s living standards. Sparrows have fewer and fewer nest sites to choose. Coupled with some other reasons, the number of sparrows has decreased sharply. The sparrow’s life is still hard.
The reason why sparrows can only jump
This is because the sparrow’s two limbs are short, which are composed of thigh, tibia, tarsal and toe. The whole hindlimb muscles are distributed in thigh and tibia, and the other parts are tendons. These tendons run through the toe end, which can control the bending of the toe, so that the sparrow can hold the branch tightly and live safely.
However, there is no joint mortar between the tibial tarsal bone and tarsal phalanx of the sparrow’s hind limb, so the joint between the tibia and tarsal bone cannot be bent, which makes the sparrow unable to walk on the flat ground, but can only jump quickly and frequently.