The 7 species of wild equid have three different strategies of social structure:
Formation of family groups
The domestic horse, Przewalski's horse, plains zebra and mountain zebra form small family groups (also called "harems" or "bands") of an adult stallion, one to three mares, and their offspring to sexual maturity. Families with more than one adult stallion can also be found in feral horse and plains zebra populations. In three populations it has been shown that these stallions form cooperative coalitions to help fight more dominant rivals. Young males, or those defeated from a family group by another stallion, form groups of bachelor stallions. Bachelor groups are found in all equid societies regardless of the other social structure.
Like all horses, the Camargue horse forms family groups © C. Feh