Animal studies

Why do we experiment with animals?

• More practical - animals breed faster than people, we can see results over multiple generations faster

• Ethical reasons

What research did Lorenz (1952) do on imprinting?

A clutch of goose eggs divided into two - half hatched with mother goose in natural habitat, half hatched in incubator where the first moving object they saw was Lorenz.

What were Lorenz’ findings?

• Incubator group followed Lorenz everywhere, control group followed their mother → stayed this way even when they were mixed up.

• If chicks did not attach themselves to a mother figure within the first few hours of hatching, they never hatched.

• Shows phenomenon of imprinting

What research did Lorenz (1952) do on sexual imprinting?

• Peacock was reared in the reptile house of a zoo, where the first moving object it saw after hatching were giant tortoises.

• As an adult, the peacock would only try to court giant tortoises.

What research support is there for Lorenz’ research?

• Regolin and Vallortigara (1995) exposed chicks to simple shape combinations that moved.

• When moving a range of shape combinations, they followed the shape that looked most like the original.

• Supports Lorenz view that young animals were born with an innate mechanism to imprint on a moving object present in the critical window of development

Why is Lorenz’ research not generalisable to humans?

Mammal attachment is different and more complex than for birds - in humans, attachment goes two ways

What research did Harlow (1958) do on contact comfort?

• 16 baby monkeys were reared with two model ‘mothers’.

• In one condition, milk was only dispensed by the wired mother, and the other only the cloth mother.

What were Harlow’s findings?

Baby monkeys sought comfort over food - cuddled the cloth mother regardless of who dispensed milk - when the wired mother dispensed milk, monkeys held onto cloth mother whilst eating.

What did Harlow’s findings show?

Contact comfort was of more importance than food in attachment

What was the effect of maternal deprivation on the monkeys in adulthood?

• Monkeys that reared with wired mother were mostly dysfunctional.

• Monkeys that reared with cloth mother were more aggressive, less social and bred less.

• When these monkeys became mothers, some neglected their young, some attacked and killed them.

What did Harlow conclude from seeing these monkeys in adulthood?

There is a critical period for attachment formation - a mother figure had to be introduced within the first 90 days of life for attachment to form - if no attachment formed, it would never happen and damage irreversible

How does Harlow’s research have real-world application?

• Howe (1998) suggests it helps social workers and psychologists understand how a lack of early attachment can affect child development, allowing them to intervene and prevent this.

• Helps understanding importance of attachment for monkeys in zoos and breeding programmes in the wild.

• Research not only theoretical - practical as well.

Why is Harlow’s research not generalisable to humans?

Both are mammals, but the human brain and behaviour is more complex than monkeys

What ethical issues are there with Harlow’s research?

Caused severe long-term distress to the monkeys - are the theoretical and practical applications more beneficial than the cost?