Affinity relations exist within the same harem between the Przewalski mares and their foals. They allow the adoption of the newborns by their mothers but also between the brothers and sisters, the different mares, and even the mares and the stallion. The horses with affinity spend more time together, engage in behavior mimetism, share food resources, groom each other, rub their heads against each other, or chase each other's insects.