Hamsters rarely eat each other, since their disputes are territorial, not predatory. Some hamsters are aggressive and can attack and kill each other, while others are aggressive but resolve their aggression through a social hierarchy.
Dwarf hamsters often live in a social hierarchy and regulate their own conflict without serious injuries or death occurring, with dominant hamsters taking territorial precedence over submissive hamsters. In some instances injuries may occur if conflicts cannot be resolved, and in that case the dwarf hamsters must be kept separate. Syrian hamsters are both solitary and aggressive, and can fight to the death over territorial disputes rather than resolve them. Syrian hamsters should always be kept individually and never in groups.