1926 Sigmund Freud’s psychoanalytic theory of “cupboard love” suggests that an infant becomes attached to a caregiver because that person is a source of food.
1935 Konrad Lorenz states nonhumans form strong bonds with the first moving object they meet—often the mother.
1951 John Bowlby argues that human mothers and infants are genetically programmed to form a uniquely strong bond.
1964 UK psychologists Rudolf Schaffer and Peggy Emerson show that infants are attached to people who do not perform feeding and caretaking duties.
1978 Michael Rutter shows that children bond with a variety of attachment figures, ...