The hamadryas baboons are very social creatures. They have one to three levels of structure in their social organization. The first level in the social organization of the hamadryas baboon is a the one male unit. The one male unit is made up of a group of up to 10 females dominated by an adult male. The females in the one male unit are non bonded and the males play the decisive roles in intra-group and inter-group interaction( Gil-Burmann et al. 1998).Each one male units may have adult or sub adult followers. The non-related sub-adult followers become attached to the group. “ They are now and then groomed by females but they seldom copulate with the females( Kummer 1968).” Two males can cooperate in leading their one male units in a two-male team. The one male unit may detach from the troop at large to forage on its own.
The second level of organization in the hamadryas baboon is the band. The band is composed of 30-90 animals usually in one-male units. Also within bands are solitary males, males who are neither leaders of a one male unit nor are they attached to a one male unit as a follower males
( Kummer 1968). The band adopts a cohesive network; they often fight against other bands. The band often feeds, forages, and travels together. The troop is third level of social organization in the hamadryas baboons. The troop is composed of several bands and often using the same sleeping rock. A troop may consist of over 200 animals. A fourth level of social organization has been observed between bands and one-male units. In a band in Ethiopia, Abegglen noticed that certain males, both solitary and with females, associated more frequently with one another than they did with other males. Abegglen saw obvious physical resemblances among these males; he proposed that they were close kin, and called their associations: clans ( Abegglen 1984).
The social spacing for the hamadryas baboons is a home range. The hamadryas baboons live in home range of about 1-40 km2 in the vast semi-desert areas of the horn of Africa, and the Arabian Peninsula( Swedell 2002). Scarcity and the dispersed nature of food is quite common in this areas so the hamadryas baboon have to travel far and wide to search for food. This is in direct contrast to the savanna baboons who are privy to plentiful yet dispersed food in the savannah. The home range of the hamadryas baboon is too large to be defended; therefore the male hamadryas baboon defend the females only and adopt a polygenous mating system. Kummer noted that it is likely that the hamadryas baboons developed the one to three level of social organization that is different from the savannah baboon in order to cope with the scarcity of food in the semi-desert areas
( Kummer 1968). The hamadryas baboon form large aggregates (troops) at night because of lack of sleeping rocks and forage in the large troops; however, they can break into basic one-male unit to efficiently forage when there is a scarcity of food.
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This Page was created by Stella Kenyi, stkenyi@davidson.edu, as student website for Biology 323, Animal Behavior, At Davidson College