Scientists started to think taxonomy needed a special name for this group of living things in 2006. They studied large numbers of data and saw a pattern that said the organisms in Olfactores had a relationship with each other that they did not have with cephalochordates. The name "olfactores" comes from Latin word "olfactus" for "sense of smell." Scientists named this clade "Olfactores" because the animals in it grow a pharynx as part of their respiratory system and use it to breathe. Cephalochordates, for example the lancelet, do not have respiratory systems and they do not have any organs whose job is only to smell things.