The celebrated Cleveland Apollo is one of the most famous works attributed to the fourth-century Attic sculptor Praxiteles. Many later marble copies survive, but this bronze classical piece came to public attention only in 2004 when it was acquired by Cleveland Museum from a German estate, where it had been since before World War II. There has been an ongoing dispute as to whether this is an ancient copy of Praxiteles’ work or whether it could be the original work. In any case, it displays a trait the marble copies do not: a pronounced volumetry of the lower abdomen, almost a saggy belly, unexpected in the portrayal of the youthful god. This unusual lower abdomen suggests an interest, unnoticed in other works, in the koiliai, the ‘pouches’ or ‘cavities’ of the belly variously described by medical authors as the hollows inside the torso where fluids are gathered, food is received, and embryos grow in females. The sculptor of this piece (or Praxiteles in sculpting the original, if this is not the original but copies this feature of the original) devoted important attention to this intriguing volumetry, and gravity in response to the torsion of the trunk; the influence of contemporary medical and biological discussions plays a plausible role here.