You may have seen on TV or brochures the images of giant pandas holding baby pandas to their belly and walk around together. Some may wonder, are they marsupial, just like kangaroos? In fact, pandas are not marsupial at all. They are not even in one family tree with koalas bears or wombats.
However, when newly born, baby pandas are really small, only weighing around 140g, 1/933 of the weight of their mothers. This ratio is shockingly small, except the marsupial like kangaroos and koalas, no other animals we know have such big a gap between the mother and the baby. The reason for such a big size gap is that giant panda cubs are typical late maturation, i.e. premature infant not fully developed.