part of part of has skeleton posterior region of body anus caudal region post-anal caudal region XAO:0000087 postsacral region Subdivision of an organism along anterior-posterior axis that is the posteriormost region, extending past the anus (or cloaca, if present), consisting of a tail in some fully formed chordates (or a tail bud in embryos). In animals that have a sacral region, this is the region immediately posterior to this. post-anal tail region tail region UBERON:0006071 caudal region of vertebral column subdivision of organism along main body axis