The newborn giant panda weighs about 80-120 kilograms, belongs to large animals. However, the newborn giant panda is very light, only about 100g, less than 0.11% of the mother's weight. Other mammals' newborns are about 3.8% of the mother's weight.

Why are giant panda cubs so light at birth?

Giant panda weight

'Anatomy' magazine once published an article, which found that giant panda cubs' skull development was immature, the newborn giant panda's skull was not mature like other bears, this is because their gestation period was short, the embryo's development was not completely mature before birth.

To study why giant panda cubs are so light, scientists CT scanned two deceased giant panda cubs and reconstructed 3D models based on the scan results.

Through this model, researchers found that giant pandas' bones are not fully developed at birth, the development level of giant panda cubs at birth is equivalent to human 28 weeks' fetal development.

The reason for this is that giant panda embryos have a short implantation time.

After fertilization, the embryo floats in the fallopian tubes and uterus for several months before implantation and development. At this time, the fetus differentiates and is connected to the mother's placenta, and the mother supplies nutrients to the fetus through the placenta.

Most bear species take two months to develop in the uterine wall, while giant pandas only take one month. That is, giant pandas have a later implantation time, which leads to underdeveloped development.

Generally, mammals try to let their cubs develop fully before birth, so that the cubs can survive. For example, giraffe cubs stand up in about 30 minutes, otherwise they may be hunted by predators such as lions.

Otherwise, the species may go extinct.

However, the giant panda is an exception, although it eats bamboo,it has carnivorous characteristicsits teeth are sharp. In addition, giant pandas live in areas where there are few large carnivorous animals, and small carnivorous animals cannot catch giant pandas. Even if giant pandas give birth to immature cubs, they will not easily go extinct.

Just because newborn giant pandas are quite immature and are born before they are fully developed, the death rate of newborn giant pandas is very high, on average, one giant panda gives birth to one cub, if it gives birth to two twins, the giant panda mother will only choose one to raise, because raising a single cub can significantly improve the cub's survival rate. Whether it is in the wild environment or captive breeding mode, giant pandas will take care of the cubs, 2-3 weeks after birth.

Giant panda development

When the giant panda is just born, its body is pink, and its body is covered with fluffy fur.

At birth, the giant panda protects them, when moving, it carries the cub in its mouth.

Giant pandas are mammals, so newborns go through maternal breastfeeding. After feeding, the mother licks the cub's body, research shows that this action can help the cub defecate.

At birth, the cubs do not open their eyes, at this time they only connect with their mothers by calling, when the mother hears the cubs calling, she responds to the cubs' needs,

After 1-2 weeks, the black part of the giant panda cubs becomes darker, at this time the giant panda's outline begins to appear.

At about 4 weeks, their black eyes, ears, and legs grow black hair.

At about 6 weeks, giant panda cubs open their eyes.

At 7-8 weeks, they start to grow teeth.

After 3 months, they start to crawl everywhere, preparing for survival.

After the giant panda weans off, it will still follow its mother to learn how to find food, which part of the bamboo is the best to eat, and even learn about the giant panda's breeding process, preparing for future breeding.

Research shows that if giant pandas learn how to breed when they are young, their breeding ability will be weaker when they grow up, it will be difficult to leave offspring in the wild, and in zoos, keepers will try to arrange for them to watch giant pandas more often.

The giant panda's estrus period is very short, only lasting 3-4 days, and because giant pandas are solitary animals, the giant panda population is scarce in the wild. When the male giant panda perceives the female's scent, the giant panda's estrus period may have ended.

In summary

Actually, there are not many species like giant pandas that are born before their bodies are fully developed and continue to develop in the outside world. Humans are one of them. Humans do not develop fully because human brains are large, and it's easy for human babies to have difficulty in giving birth when they grow up.

However, there is no mainstream explanation for why giant pandas are born before they are fully developed, and with the development of science, humans may be able to solve more mysteries of giant pandas.