Animal studies
Studies carried out on non-human animal species for ethical or practical
reasons ( animals breed faster so researchers can see results across many
generations)
Lorenz's research
Procedure
Randomly divided a clutch of goose eggs- half were hatched with their mother in their natural
environment, the other half hatched in an incubator where the first moving object they saw was
Lorenz
Findings
Incubator group followed Lorenz everywhere
Control group (born with mother) followed her everywhere even when
the two groups were mixed up
Proof of imprinting: precocial species attach to and follow the first moving
object they see
He identified a critical period (time period in which imprinting has to take place) of a
few hours. Any time which exceeds this, attachment will not occur
Sexual imprinting
Relationship between imprinting and adult mating preferences
Birds imprinted on a human would later display courtship behaviour towards humans
Example
A peacock was reared in a reptile house and the first moving object it
saw was a giant tortoise. Later, it only directed courtship behaviour
towards giant tortoises.
, Animal studies
Evaluation Lorenz
Cons
&
Lack of generalisability to humans
There's a problem generalising birds to humans.
The mammalian attachment system is quite different from that in birds. Eg. Mammalian mothers show
more emotion. And differences in critical periods
Mammals can form attachments at any time = not appropriate to generalise Lorenz's ideas to humans
Ex
Lorenz's observations have been questioned
P
Guiton et al found that chickens imprinted on yellow washing up gloves actually, with
Ev experience, preferred mating with other chickens
This opposes Lorenz's theory that imprinting has a permanent effect on mating
Et behaviour.
Suggests that mating behaviour isn't as permanent as Lorenz proposed
, Animal studies
Harlow's research
Procedure
Tested the idea that comfort overrides food in attachment
He reared 16 baby monkeys with two wire 'mothers'
One condition = milk dispensed by plain wire mother
Other condition = milk dispensed by cloth-covered mother
Findings
The monkeys preferred the cloth mother 36% of the time
They sought comfort from the cloth mother when frightened
Shows that contact comfort is more important than food in attachment
He then followed upon monkeys who had been deprived of a 'real mother
Maternal deprivation has large effects:
• those reared with wire mothers were most dysfunctional
• AlI were more aggressive, less sociable and bred less often
Concluded that there's a critical period of 90 days for attachment to
form in these monkeys
Studies carried out on non-human animal species for ethical or practical
reasons ( animals breed faster so researchers can see results across many
generations)
Lorenz's research
Procedure
Randomly divided a clutch of goose eggs- half were hatched with their mother in their natural
environment, the other half hatched in an incubator where the first moving object they saw was
Lorenz
Findings
Incubator group followed Lorenz everywhere
Control group (born with mother) followed her everywhere even when
the two groups were mixed up
Proof of imprinting: precocial species attach to and follow the first moving
object they see
He identified a critical period (time period in which imprinting has to take place) of a
few hours. Any time which exceeds this, attachment will not occur
Sexual imprinting
Relationship between imprinting and adult mating preferences
Birds imprinted on a human would later display courtship behaviour towards humans
Example
A peacock was reared in a reptile house and the first moving object it
saw was a giant tortoise. Later, it only directed courtship behaviour
towards giant tortoises.
, Animal studies
Evaluation Lorenz
Cons
&
Lack of generalisability to humans
There's a problem generalising birds to humans.
The mammalian attachment system is quite different from that in birds. Eg. Mammalian mothers show
more emotion. And differences in critical periods
Mammals can form attachments at any time = not appropriate to generalise Lorenz's ideas to humans
Ex
Lorenz's observations have been questioned
P
Guiton et al found that chickens imprinted on yellow washing up gloves actually, with
Ev experience, preferred mating with other chickens
This opposes Lorenz's theory that imprinting has a permanent effect on mating
Et behaviour.
Suggests that mating behaviour isn't as permanent as Lorenz proposed
, Animal studies
Harlow's research
Procedure
Tested the idea that comfort overrides food in attachment
He reared 16 baby monkeys with two wire 'mothers'
One condition = milk dispensed by plain wire mother
Other condition = milk dispensed by cloth-covered mother
Findings
The monkeys preferred the cloth mother 36% of the time
They sought comfort from the cloth mother when frightened
Shows that contact comfort is more important than food in attachment
He then followed upon monkeys who had been deprived of a 'real mother
Maternal deprivation has large effects:
• those reared with wire mothers were most dysfunctional
• AlI were more aggressive, less sociable and bred less often
Concluded that there's a critical period of 90 days for attachment to
form in these monkeys
