“…If formed, polygynous group formations tend to be short-lived: subordinate females that have started breeding usually leave the group after one pregnancy, either by spontaneous migration or after being evicted by the dominant female [7,8,16,17,20,24]. Survival of infants born to subordinates is low [8,17,23,25], and dominant females have been observed killing the subordinate female's infants [18,23,26], especially if these were born shortly before or after the dominant female's own infants [23,25]. Competition for helpers to provide co-operative infant care might limit the number of breeding females per group [8,18,23,25,26].…”