“…For older offspring, it might improve their infant care skills by gaining experience with siblings (Hoage, 1978;Epple, 1978;Tardif et al, 1984;Cleveland and Snowdon, 1984;Pryce, 1988Pryce, , 1993Baker and Woods, 1992;Snowdon, 1996;Sousa et al, 1997), increase the likelihood of inheriting a breeding position by staying in the social group (Goldizen and Terborgh, 1989;Ferrari and Diego, 1992;Baker et al, 1993), especially in saturated areas, since breeding opportunity outside the group may be limited and increase inclusive fitness gains through caring for and improving the survival of relatives (Garber et al, 1984). On the other hand, the costs for fathers and older offspring related to caring behavior seem to be the energetic cost of infant transport during traveling (Kirkwood and Underwood, 1984;Goldizen, 1987;Price, 1992;Sanchez et al, 1999), the increased risk of predation leading to the use of anti-predator strategy by caretakers (Caine, 1993;Tardif, 1994Tardif, , 1997Snowdon, 1996), and reduced foraging time during infant transport (Goldizen, 1987;Price, 1992;Digby and Barreto, 1996). The final outcome of infant care is the reproductive success of the father and inclusive fitness of the siblings.…”