Who created the monkey experiments, to see if the monkey favored comfort over nourishment?

Harry Harlow conducted rhesus monkey experiments in the 1950s-60s showing that infant monkeys preferred a soft cloth 'mother' over a wire mother that provided food. This demonstrated that contact comfort and emotional attachment are more important than nourishment for mother-infant bonding. Harlow's work overturned behaviorist assumptions that attachment stems solely from feeding and highlighted the importance of emotional bonds.