Animal Studies Flashcards
Lorenz 1935 - APFC
Aims- To see how the young goslings formed an attachment with a ‘parent figure’. Also, investigate the mechanisms of imprinting.
Procedure- Lorenz split a large clutch of gosling eggs and divided them into 2 groups. One remained with their natural mother, the other were put into an incubator with Lorenz. When the incubator eggs hatched the first moving thing they saw was Lorenz. Showed following behaviour. To test the effect of imprinting, he marked each group so he could tell which each one was from. Placed them all under an upturned box. Him and the natural mother were both present.
Findings- The goslings quickly divided themselves up and the naturally hatched goslings followed their mother while the incubator hatched goslings followed Lorenz. Intubated eggs showed no bonds to their natural mother, these bonds proved to be irreversible. Process of imprinting is restricted to a definitive period of the young animal’s life (called a critical period). This is between 4 and 25 hours after hatching. Imprinting is a process similar to attachment in that it binds a young animal to caregiver in a special relationship. Imprinting to humans does not occur to some birds like curlews
Which animal is imprinting behaviour associated with?
Imprinting is mainly exhibited by nidifugous birds, which are the ones that leave nest early. Imprinting leads to close contact being kept by the first moving object that is encountered.
Features of imprinting
-Process is irrreverisble and long lasting
-Has an effect on later mate preferences (sexual imprinting)
Strength of Lorenz’s research
-His research supports the concept of imprinting
-His research has helped well recognised theories as it proves that attachment formation takes place during a critical period of time
Weaknesses of Lorenz’s research
-Criticised for extrapolation as humans and birds are physiologically different
-Findings can’t be generalised as the way a human infant develops an attachment with their primary caregiver is a lot different to the way a gosling does
-Researchers like GUITON ET AL 1966 have questioned Lorenz’s conclusions of it being irreversible as he found that chicks who imprinted on yellow washing up gloves tried to mate with them as adults, but with experience they gained to prefer chickens
Overall suggesting that the impact of imprinting on mating behaviour is not as permanent as Lorenz believed
Why is it hard to generalise birds to humans?
The mammalian attachment system is very different to birds. This is because mammalian mothers like to show more emotional attachment to their offspring. So overall, it is not appropriate to generalise any of Lorenz’s findings to humans.
Harlow 1959 - APFC
Aims- To investigate the behaviour of infant monkeys who were separated from their mother at birth to assess the effects of separation on their later behaviour.
Procedure- 2 wire “mothers”, each different heads, one condition the milk was dispensed by a plain wire mother, in the other condition milk was dispensed by a cloth covered wire mother. Their preference for which mother was measured. 8 infant rhesus monkeys studied for a period of 165 days. 4 monkeys had milk from the cloth covered mother whilst the other 4 has milk from the plain wire mother. Harlow measured how long each infant spent with each mother. Also carried out another measure of attachment by exposing them to a frightening mechanical teddy bear to see which mother they would seek for comfort.
Findings- All 8 monkeys spent the most time with the cloth covered mother regardless whether or not she had milk. When they were fed by the wire mother, they immediately returned to the cloth covered mother. When they were frightened, played with toys they kept very close to the cloth mother for reassurance.
Conclusion- Based on these findings, it suggests that infants don’t develop attachments to who feeds them, but rather who offers contact comfort. Harlow continues to study his monkeys as they grew up and found that all of the motherless monkeys (even with the contact comfort) grew up abnormally. They were socially abnormal- fled/froze when approached by other monkeys, and they were sexually abnormal- didn’t show normal mating behaviour, didnt cradle their babies and even some mothers killed their offspring.
Strength of Harlow’s research
-It has important practical applications. Helps social workers to understand the risk factors in neglect and abuse by helping them to intervene and prevent it.
-Also helps us to understand the importance of attachment figures for monkeys in zoos
The usefulness of Harlow’s research increases its value
Weaknesses of Harlow’s research
-Faced severe criticisms for the ethics of his research
-Ethical issues as rhesus monkeys are considered to be similar enough to humans to be able to generalise their findings, so presumably their suffering was also quite human like
-Harlow was aware of it he named the wire mothers “iron maidens” after a medieval torture device
-Confounding variable as the 2 stimulus objects varied in more ways other than clothing or not. The heads being different acted as a confounding variable because it varied systematically with the independent variable. So possibly the monkeys did favour the mother with the more attractive head.
-Lacks internal validity as firm conclusions cannot be drawn
What theoretical and practical value does Harlow’s research have?
-Showed us the importance of the quality of early relationships for later social developments. (Essentially mothers and peers)
-Monkeys raised in total isolation were impacted for life
-Bond between mother and child in the first few years essential for mental health and development of child.
-Helped us to discover RAD (reactive attachment disorder) as being from emotional neglect or abuse at a young age
