[1] Another common characteristic is the spermaceti, a semiliquid waxy white substance filling the 'case' or spermaceti organ in the whale's head, which plays a primary role in the production and directional manipulation of focused clicking sounds used for echolocation in the extant great sperm whale (Physeter macrocephalus).

All species congregate in 'pods' or herds, consisting of mostly females, calves, and adolescent males, although these pod sizes are typically smaller in the kogiids.

[1] The earliest sperm whale fossils are known from the late Oligocene – about 25 million years ago,[3][4] with an ancestry tracing back from the latest Eocene before diverging from the remainder of the odontocetid line, leading to the dolphins, and porpoises.

[5] The close relationship between extant Physeteridae and Kogiidae is confirmed in recent molecular studies using mitochondrial cytochrome b,;[6][7] on the basis of these analyses, their nearest relatives appear to be the Ziphiidae on one hand, and the Mysticeti and Platanistidae on the other.

The last cited paper also favours the grouping of Physeteridae and Kogiidae in a single superfamily, Physeteroidea, as has sometimes previously been suggested.