When is a thumb not a thumb? When it’s an elongated wrist bone of the giant panda used to grasp bamboo. Through its long evolutionary history, the panda’s hand has never developed a truly opposable thumb and instead evolved a thumb-like digit from a wrist bone, the radial sesamoid. This unique adaptation helps these bears subsist entirely on bamboo despite being bears (members of the order Carnivora, or meat-eaters). In a new paper published in Scientific Reports, the Natural History Museum of Los Angeles County’s Curator of Vertebrate Paleontology Xiaoming Wang and colleagues report on the discovery of the earliest bamboo-eating ancestral panda to have this “thumb.” Surprisingly, it’s longer than its modern descendants.
Click here for original story, Pandas gave bamboo the thumbs up at least six million years ago
Source: Phys.org