Giant panda years ago) from the main ursine stock; since it is the most basal member of the group, it is equidistant from all other extant ursids. The giant panda has been referred to as a living fossil. Despite the shared name, habitat type, and diet, as well as a unique enlarged bone called the "pseudo thumb" (which helps them grip the bamboo shoots they eat) the giant panda and red panda are only distantly related. The word "panda" was borrowed into English from French, but no conclusive explanation of the origin of the French word "panda" has been found. The closest
Giant panda was omnivorous 7 million years ago (mya), it only became herbivorous some 2-2.4 mya with the emergence of "A. microta". Genome sequencing of the giant panda suggests that the dietary switch could have initiated from the loss of the sole T1R1/T1R3 umami taste receptor, resulting from two frameshift mutations within the T1R1 exons. Umami taste corresponds to high levels of glutamate as found in meat and may have thus altered the food choice of the giant panda. Although the pseudogenization of the umami taste receptor in "Ailuropoda" coincides with the dietary switch to herbivory, it is likely a result of,