Why the number of the panda is so few? Besides the changing of the environment, giant panda's own unique physiological characteristics decides its special ecological status, for example the "delayed implantation". "Delayed implantation means that after formation, early embryos cannot implant immediately, but float free in the uterus for a long time. During this period the early embryos stop growing until the body has started a mechanism, free embryos just begin to implant in the uterus, and grow into fetus. Fertilized embryos may stop growing by any accident during its floating in uterus.

　　Giant pandas experience embryonic diapause, also known as delayed implantation, where the fertilized egg divides into a ball of cells called a “blastocyst”. At this stage development is halted, and the blastocyst free-floats in the uterus without growth until it is the right time to implant in the uterine wall. If the environment is suitable for implantation and the female panda has enough nutrition, the egg will attached itself and transition into a fetus.

　　The gestation period of panda very short (83-200 days), and their development time of the implanted embryos is extremely short. Every newborn cubs are premature, whose weight is only 1/1000 of their mother(100-200 grams on average) and they are easy to get sick or die. Therefore they need carefully care. There is no hope of survival if panda mum cannot nurse her baby, or the baby did not get good care timely after birth. In order to improve the rate of survival, panda mum has to choose the stronger baby to raise if she get twins.

Newborn baby

　　People hardly recognizes that it is a panda when they see panda baby for the first time because it is so tiny, with little fur and underdeveloped organs. The newborn baby is so fragile that it all depends on the carefully nursing of panda mum or panda keepers.

This panda baby is only about 50 days old, which looks very small. Till now it’s easy for you to finger out it is a panda .It can’t live without mum’s help.

Panda is riding horse

　　When the panda is about 5 months old, it’s the time to learn and try all the fresh things, such as, climbing trees, playing toys and learning more survival skills. Panda’s movements are not very agile, but they can do it better gradually.

I’m a teenager

　　One year old panda weighs about 30 kg. It looks very cute and naïve, but it already has strong consciousness to defend against enemies. And this is not enough, it still has to live with its mum to learn more survival skills. When a panda is about 2.5years old, it can live by itself, like finding food, fighting against enemy and competing for territories.

　　The growth of giant panda is a very difficult processes, panda has to pay more efforts because the body constitution is unusual weak and it is easy to die.

Information source: Giant Panda Ex Situ Conservation Theory and Practice by Zhang Zhihe and Wei Fuwen