Final answer:
Harry and Margaret Harlow concluded from their studies on rhesus monkeys that social comfort and emotional bonds are more essential to early development than just providing food, leading to significant insights about attachment and social development.
Step-by-step explanation:
Harry and Margaret Harlow's renowned research on rhesus monkeys led to the conclusion that social comfort is more crucial for early development than merely the provision of food. Conducted between 1957 and 1963, their experiments compared the effects of two surrogate mothering situations on young monkeys: one with a mesh and wire sculpture, and another with a soft terrycloth "mother." The Harlows observed that the monkeys overwhelmingly preferred the terrycloth substitute, which resembled a rhesus monkey but did not provide food, over the wire model that provided nourishment. This preference suggested that the sense of comfort and security was of greater significance than the basic need for sustenance.
Further studies highlighted that isolation in early life could lead to severe developmental and social difficulties as the monkeys grew. Their work showed that psychological needs in infancy go beyond physical needs, indicating that the emotional bond with a caregiver is critical for healthy psychological development and well-being. Therefore, Harlow's contribution had a profound impact on understanding attachment, social development, and the essential needs of primates, including humans.
It is important to note, Harlow's methods, seen as unethical by today's standards, highlighted the necessity of ethical guidelines in research. Nonetheless, Harlow's findings on the importance of social experiences remain a valuable foundation for modern psychology and primatology.