 These were often linked to goums, but where a goum would generally consist of people all with the same herd type, descent groups were frequently split up over several economic activities, thus allowing a degree of 'risk management'; should one group of members of a descent group suffer economically, the other members of the descent group would be able to support them.Whilst the phrase "descent group" suggests purely a lineage-based arrangement, in reality these groups were fluid and adapted their genealogies to take in new members.The largest scale of tribal interactions is the tribe as a whole, led by a "Sheikh" ( "", literally, "old man"), though the title refers to leaders in varying contexts.