What were the findings of Harlow's research on maternal deprivation

Harlow made use of rhesus monkeys to study maternal deprivation and found that, when they are placed in a scary environment, the monkeys were more likely to cling to the cloth artificial monkey than the iron one, indicating contact comfort. This went against some ideas from other researchers that feeding is the most important process in bonding between the mother and infant. He also found that, when an elder monkey was introduced into the cage with the deprived, the deprived monkey clung to the older one and followed them round in order to catch up with the development of socialisation skills that they had missed through being deprived for the 165 days.