A newborn giant panda is so tiny that it is about 900 times smaller than its mother.

Giant pandas have one of the strangest pregnancies of any mammal. Researchers at Duke University found that panda cubs are born with skeletons that aren't fully finished yet. This happens because of something called delayed implantation. The tiny egg floats around inside the mother for months before it finally attaches and starts growing into a baby.Because the mother panda mostly eats bamboo, she doesn't get a lot of energy from her food. This makes it hard for her to grow a big baby inside her body. Instead, the baby is born very early and very small, weighing only about 100 grams (3.5 ounces). The mother then uses her energy to make extra-rich milk to help the baby grow outside the womb.A human baby is usually about 1/20th the size of its mother, but a panda baby is 1/900th of its mother's size. Because they are so small and weak, they can't even go to the bathroom or stay warm on their own. Their famous black-and-white patches don't even show up until they are about three weeks old. This is why panda moms are so protective and will sometimes go days without eating just to stay with their tiny cubs.