A SOCIOGRAM FOR THE CRANES OF THE WORLD

The behavioral repertoire for the world's 15 species of cranes include s over 100 behavioral acts with clear social significance. Each specie s performs at least 60 discrete social postures, vocalizations, displa ys, and activities. Because all but a handful of the stereotyped socia l displays are common to all species, the presence or absence of socia l displays was useful only to a limited degree in comparing the relate dness of established crane taxonomic groups. However, the breadth of t he repertoire for each species and for the family Gruidae tentatively places cranes at the apex of social complexity (at least for stereotyp ed displays) in the animal world. (C) 1998 Elsevier Science B.V. All r ights reserved.