Smaller monkeys, such as tamarins and marmosets, are seemingly ignored as prey by this species. The Callitrichidae contains the two general species of marmosets and tamarins. Under these conditions, marmosets waited significantly longer for food than tamarins. Many zoos observe interesting behaviors of Emperor tamarins held in captivity. Golden lion tamarins are native to the Atlantic Forest of Brazil. The four species of lion tamarins make up the genus Leontopithecus. In 1987, estrous synchrony was reported in female golden lion tamarins by French and Stribley. There are no protected areas that overlap with the Brazilian populations of emperor tamarins. The golden lion tamarins are located in the South American house. In the instances of maternal infanticide in tamarins, there were multiple breeding females. This social grouping in cotton-top tamarins is hypothesized to arise from predation pressure. Golden lion tamarins are social and groups typically consist of 2-8 members. The habitat of the tamarins also affects their behavior and social interactions. The tamarins feed over large distances, looking for insects. There is also an island in the flamingo part for Emperor Tamarins.