Mother-infant separation in the java monkey (Macaca irus).

Twelve mother-infant pairs of Macaca irus monkeys were divided into 6 groups of 2 mother-infant pairs each.During a 3-week separation period, infants in 2 groups received substitute mothering while infants in another 2 groups did not.Infants in the remaining 2 groups were separated and immediately reunited with mothers.During reunion, mothers in half of the groups were returned to their original home cages, and mothers in the remaining half were returned to identical but spatially reoriented home cages.During separation, infant playing and related behavior d e creased.The effects could not be attributed to the traumatic process of forceful removal of mothers since separation and imme diate return of mothers had a minimal effect on infant behavior.During reunion, infants responded differentially to their own mothers regardless of location of return.Although most behaviors returned to pre-separation levels, there was an indication of prolonged disturbance in the form of an intensified mother-infant relationship for 3-week separated animals.Substitute mothering, although it did not alleviate the debilitating effects of separa tion, did facilitate recovery in reunion.Species differences in the reaction to maternal separation were discussed.vi