part of part of in taxon develops from develops from derived from ancestral fusion of derived from ancestral fusion of composed primarily of Archosauria skeleton of pes metatarsal bone bone tissue pes bone tarsometatarsus UBERON:0008195 Wikipedia:Tarsometatarsus found in birds The tarsometatarsus is a bone that is found in the lower leg of certain tetrapods, namely birds. It is formed from the fusion of several bones found in other types of animals, and homologous to the mammalian tarsal (ankle) and metatarsal (pes) bones. Despite this, the tarsometatarsus of birds is often referred to as just the tarsus or metatarsus. tarsal skeleton tarsometatarsus cartilage element tarsometatarsus endochondral element