Complex sentence: Dominance is established without blood-shed, as most dogs within a group tend to be related to one another in some way, and when not this is not the case they have a submission-based hierarchy, instead of a dominance based one.
Split into simpler sentences: Dominance is established without blood-shed, as most dogs within a group tend to be related to one another in some way, and even when not this can occur. They have a submission-based hierarchy, instead of a dominance based one.