Animal Studies: Lorenz’s Geese Flashcards
Why would animal studies be used rather than human studies
Research studies are carried out on non-humans either for ethical or practical reasons.
Animals breed faster than humans and researchers are interested in seeing results across more than one generation of animals.
What is imprinting
When organisms have a biological propensity (predisposition) to form attachments to one single subject
What was the Aim of Lorenz (1935)
Aim: To examine the phenomenon of imprinting in non-human animals
(where an offspring follows and forms an attachment bond to the first large
moving object they see after birth).
What was Lorenz (1935) method?
Method: Lorenz conducted an experiment where he randomly divided greylag goose eggs into two batches.
Batch 1 (control group) – hatched naturally by their mother
Batch 2 (experimental group) – placed in an incubator with Lorenz making sure he was the first large moving object that the goslings saw after hatching.
What were the findings for Lorenz (1935)
Results: Naturally-hatched goslings followed their mother goose, whereas the incubator-hatched goslings followed Lorenz – showing no attachment to their biological mother.
Lorenz noted that imprinting only occurred within a critical period of 4-5 hours (13-16 too) after hatching which then persisted over time and proved to be irreversible.
Conclusions: These results suggest that imprinting is a form of attachment that is exhibited by birds that typically leave the nest early, they imprint onto the first moving object they encounter after hatching.
What is sexual imprinting
organisms that imprint onto other organism often display later feelings towards that organism or similar organism.
Lorenz’s Case Study: Sexual Imprinting?
In a case study Lorenz (1952) described a
peacock that had been reared (brought
up) in the reptile house of a zoo, where
the first moving objects the peacock saw
after hatching were giant tortoises.
As an adult the bird would only direct
courtship behaviour towards giant
tortoises.
What is a limitation of Lorenz (1935) study? (animal)
P: A limitation of Lorenz’s research is that he only studied non-human
animals, which means that the results cannot be generalised to humans.
E: The attachment formation in mammals appears to be very different to that
of the bird species, specifically mothers, showing more emotional reactions
to their offspring with the added ability of being able to form attachments
beyond the first few hours of birth.
C: So, caution must be applied when drawing wider conclusions about the
results.
What is a limitation of Lorenz (1935) study? (further research)
P: A further limitation comes from further research into the conclusions that Lorenz drew from his case study on imprinting.
E: Guiton at al. (1966) found that chickens would imprint on yellow washing up gloves is that was the largest moving object they saw after birth – they would then try to mate with the object in adulthood. However Guiton disagreed with Lorenz’s predictions that this was irreversible. With experience, the chickens could eventually learn to prefer mating with other chickens instead.
C: Suggesting that the effects of imprinting may not be as permanent as initially thought.
