What was an unexpected finding in Harlow's experiment?

In Harlow's experiment, the unexpected finding was that the monkeys showed a strong preference for the figure that offered comfort over the one that provided food. This outcome was significant as it highlighted the importance of emotional support and nurturing in attachment formation, challenging the previously held belief that basic biological needs, like hunger, were the sole factors driving attachment behavior in infants.

Harlow used two surrogate mothers: one made of wire that dispensed formula, and the other covered in soft cloth that did not provide food. The baby monkeys overwhelmingly chose to spend time clinging to the comforting, soft figure even when they were hungry, demonstrating that their need for emotional security and comfort outweighed their need for physical nourishment. This finding underscored the importance of emotional bonds in development, reinforcing the notion that attachment is not solely about meeting physical needs but also about the provision of security and affection.