China’s peculiarly rare animals, giant pandas, although mainly vegetarian, still belong to the order of carnivora. In terms of external forms and internal organs, giant pandas are similar to the meat-eating bears. But at the same time, the giant pandas bear the characteristics of raccoons. Indeed, the panda is so mysterious that some taxonomists have set up a specific family branch for the giant pandas alone.
Compared with other Carnivorous animals, the giant panda’s cracked teeth have been degraded, and the molars’ chewing surface has also become wider. Plants are their main source of food. Regarding the origin and classification status of giant pandas, the academic community has been arguing since 1869. The reason is that, in addition to the fact that the existing giant panda itself is very special in shape and structure, the main problem is the lack of fossil basis.
In the past century, paleontologists have discovered hundreds of places where fossils of giant pandas are buried in Asia and mainly in China. These fossils provide a clearer understanding of the evolutionary history of giant pandas since 2 million years ago. But, whether it is the early Pleistocene giant panda or the late-Pleistocene giant panda , pandas of the distant past are not fundamentally different from the existing giant pandas — at least in terms of the shape and structure of skulls and teeth, except for their different body shapes.
The giant panda species that lived 2 million years ago is only about half the size of the existing giant panda and is the most primitive species of pandas known to date. According to the dental wear marks and chewing characteristics, it can be inferred that the diet of giant panda species has basically been based on bamboo and other plants, indicating that as early as 2 million years ago, giant pandas were already vegetarian.
But, what exactly did the ancient giant panda look like? Bears that once lived in Eurasia and North America during the Miocene and Pliocene were once seen as having a direct relationship with giant pandas, but they have only a few common features with giant pandas, which has made it difficult for scientists to accept the relationship as evident.
In the meantime, Chinese paleontologists have found some sporadic dental fossils in the brown coal layer in the Chinese province of Yunnan. From the occlusal surface morphology and the structure of these teeth, the panda from whom the teeth came from already possessed the characteristics of a number of existing giant pandas.
This panda was named the first panda, which is the earliest known giant panda ancestor in the world, and somewhat affirmed the genetic relationship between the giant panda and the bear family. Prior to this, a small number of non-Chinese panda tooth fossils were found in the lignite layer of Europe and Hungary, which were dated to a later time than that of the first panda. However, these pandas are not descendants of the modern giant panda and it is difficult to judge whether they are also the ancestor of the existing giant pandas.
From the discovered fossils, it’s clear that the giant pandas migrated to Europe and Asia in the late Miocene. The limitation of the distribution of the existing giant pandas then should have begun from the Pliocene. Both the first panda and the non-Chinese pandas came from the brown coal layer. These pandas lived in marshland and therefore could not have fed on bamboos. So when did giant pandas start eating bamboos? Why would they want to eat bamboo anyway? These are still mysteries.