From the perspective of blood relations, giant panda bears are kind of a remote relative with black bears, although the two families have separated the paths six million years ago. So if we look at pandas from their origin, they belong to carnivores, which means in theory pandas can eat meat, but as we all know, pandas now only eat bamboo, making themselves vegetarians, i.e. herbivores.
Despite the fact that pandas are now vegetarian, their intestinal tracts and digestive system are far different from other herbivores; instead of having long and thin testinal tracts or complated stomach, giant pandas’ digestive tracts are short, broad and simple. In the meantime, people found out that pandas’ do not have sufficient enzyme in the digestive system to help digest fibres like other herbivores do. That’s why the huge amount of bamboo pandas have been eating everyday comes out in poop half-digested.>