EXOTIC habitat, rarity, striking coloration, and an appealing countenance have combined to surround the giant panda (Ailuropda melanoleuca) with an aura of mystery unmatched by most other mammals. Nonetheless, we really know little about the species, a lack perhaps best exemplified by the long-standing controversy about the giant panda's phylogenetic position among the arctoid (canoid plus pinniped) carnivores. There is general agreement that its closest affinities are with the ursids (bears) or procyonids (raccoons), but then the argument begins. The usual possibilities considered are: (1) The giant panda's closest relative is the lesser panda (Ailurus fulgens); as this is usually classified among the procyonids, the giant panda should be also. (2) The two pandas belong together in a separate arctoid family. (3) The giant panda is a somewhat aberrant bear and therefore belongs among the Ursidae1,2.