The giant panda family has existed on Earth for about 8 million years since its ancestors diverged from other bear species. Besides the modern giant panda, prehistoric pandas can be classified into one family, one subfamily, two genera, three species, and two subspecies.
The classification of “one family, one subfamily” indicates that all giant pandas belong to the family Ursidae and the subfamily Ailuropodinae. The “two genera” refer to the primarily carnivorous genus Ailuropoda and the almost exclusively herbivorous genus Bamboo Panda. The “three species” include the species from the genus Ailuropoda: Lufeng and Yuanmou pandas, and the small giant panda from the Bamboo Panda genus. The “two subspecies” refer to the extinct Wuling Mountain panda and the Ba’s panda among modern giant pandas.
The Lufeng panda lived approximately 8 million years ago, while the Yuanmou panda existed around 7 million years ago. The Yuanmou panda was slightly smaller than the Lufeng panda and exhibited morphological and dental traits more similar to those of the Bamboo Panda genus.
The small giant panda thrived around 2.5 million years ago. Its fossils were discovered and named by renowned Chinese archaeologist Pei Wenzhong in 1962, who is also known for finding the skull of “Peking Man.” The name reflects its smaller size; fossil evidence shows that the small giant panda was the smallest member of the giant panda family, measuring about half the size of modern giant pandas. This species was widely distributed in regions such as Guangdong, Guangxi, Sichuan, and Shaanxi, and it was part of the famous “Giant Panda-Sabre-toothed Cat Fauna.” Its distribution range and body size did not significantly differ from those of later giant pandas, leading mainstream scholars to consider it a normally developing species.
The Wuling Mountain panda fossils were discovered in 1982 and named after the mountain range where they were found. This panda lived about 1.6 million years ago and exhibited a transitional morphology between the small giant panda and the Ba’s panda, being larger than the former but smaller than the latter. The Ba’s panda, which lived between 700,000 and 100,000 years ago, could reach up to 2 meters in length as an adult, making it the largest known giant panda. It also had the widest distribution and the most abundant fossils among the panda family. Isotope analysis of its fossil remains indicates that the Ba’s panda had a more varied diet than primarily bamboo. Morphologically, it is considered a prehistoric subspecies of the modern giant panda, often referred to as the “Ba’s subspecies of the giant panda.”