How Pandas Survive Solely on Bamboo: Evolutionary History
Published:06 Jul.2022 Source:Natural History Museum of Los Angeles County
While the celebrated false thumb in living giant pandas (Ailuropoda melanoleuca) has been known for more than 100 years, how this wrist bone evolved was not understood due to a near-total absence of fossil records. Uncovered at the Shuitangba site in the City of Zhaotong, Yunnan Province in south China and dating back 6-7 million years ago, a fossil false thumb from an ancestral giant panda, Ailurarctos, gives scientists a first look at the early use of this extra (sixth) digit-and the earliest evidence of a bamboo diet in ancestral pandas-helping us better understanding the evolution of this unique structure.
"Deep in the bamboo forest, giant pandas traded an omnivorous diet of meat and berries to quietly consuming bamboos, a plant plentiful in the subtropical forest but of low nutrient value," says NHM Vertebrate Paleontology Curator Dr. Xiaoming Wang. "Tightly holding bamboo stems in order to crush them into bite sizes is perhaps the most crucial adaptation to consuming a prodigious quantity of bamboo."