The aardvark is not closely related to the pig; rather, it is the sole extant representative of the obscure mammalian order Tubulidentata,[7] in which it is usually considered to form one variable species of the genus Orycteropus, the sole surviving genus in the family Orycteropodidae. The aardvark is not closely related to the South American anteater, despite sharing some characteristics and a superficial resemblance.[9] The similarities are based on convergent evolution.[10] The closest living relatives of the aardvark are the elephant shrews, tenrecs and golden moles.[11] Along with the sirenians, hyraxes, elephants,[12] and their extinct relatives, these animals form the superorder Afrotheria.[13] Studies of the brain have shown the similarities with Condylarthra,[10] and given the clade's status as a wastebasket taxon it may mean some species traditionally classified as "condylarths" are actually stem-aardvarks