Lecture 18: Human and animal Flashcards
Define personality
Individuals from the same species that differ from each other in their behaviour, the variation is temporally consistent. These behaviours generalise across contexts, to some extent, they’re heritable and they can have fitness consequences.
Briefly describe the history of personality
People used to think that individual differences in behaviour was just noise and were non-adaptive, random behaviours. People then realised that these behaviours could be advantageous and can produce variability and selective advantages. This is because if individuals act differently in certain situations, some will be more likely to survive.
Why is it important to study personality?
To understand a species and the strategies individuals employ in order to survive and reproduce. It allows us to compare these organisms to humans, and complete studies that couldn’t be done with humans as there isn’t much control of the environment and genetics. It also has practical implications like human-animal interactions, animal welfare and conservation.
How do anthropomorphic psychologists measure personality?
They use self-rating questionnaires and assess knowledgeable informants (parents, friends). They define personality by using human terms that don’t fit to animals like curiosity and being sympathetic. They gather the scores and scales and compare them with human personality theories.
How do biologists measure personality?
Through observations, experiments and assessments of knowledgeable informants like their owners and observers. This method is also anthropomorphic in the sense that it relates an animal’s behaviour to human traits like curiosity.
What are the levels of analysis when measuring personality?
Population specific personality traits that can’t be compared across species and universal personality traits that are consistent across species. This includes boldness and aggression. However, it isn’t always appropriate to compare across species as personality is very biologically influenced. For example, an escape response is easily triggered in antelopes compared to lions so does this mean that all antelope are shy and all lions are bold? No. They behave like this because of ecological pressures, e.g. being hunted. A personality trait is real if between-individual variation > within-individual variation.
Describe the diagnostic criteria of validity in terms of measuring personality
There needs to be a correspondence between ratings and observed behaviour, to ensure this, you need to: have knowledge on the species’ behaviour, control for confounding variables, have naive independent observers and have ecological validity. For example, a mouse lemur’s behaviour will be different if you put them in a novel setting compared to presenting them with a novel object in their natural setting when exploring boldness. Furthermore, a measure in a novel task wouldn’t correspond to a measure in an ecologically valid feeding task when looking at boldness.
Describe the diagnostic criteria of reliability in terms of measuring personality
There needs to be a correspondence between the multiple observers, you should problem with items that don’t have a clear association with behaviour like jealousy, have a standardised procedure with either inter or intra observer reliability which is often missing and it should be replicable, for example crested macaques have a consistent personality over time.
Discuss some evidence for personalities in animals
Part 1: The chaffinch study
Quinn 2005 found that some chaffinches are hyperactive and some are hypoactive. There was a correlation between behaviour type and anti-predator response. Hypoactive chaffinches were less likely to try and escape when at high risk and more likely to freeze when at low risk of being caught by the hawk. The hyperactive chaffinch more likely to try and escape at high risk and less likely to freeze when at low risk. So the different types were favoured under different predation pressures.
Discuss some evidence for personalities in animals
Part 2: The bighorn sheep study
Reale 2000 measured personality in terms of approaching a salt lick associated with capture traps and the time the sheep spent there. Bold individuals stayed there longer, which correlated to their reproduction. The bold sheep reproduced earlier and had a higher weaning success as they were more willing to access dangerous areas and have access to valuable foods.
Discuss some evidence for personalities in animals
Part 3: The rhesus macaque studies
Prenatal stress impaired the mother’s offspring’s neuromotor development and caused attention deficit. This persisted over time and inhibited the macaque’s personality as it made them less active and less socially engaged.
Rhesus macaques who had a negative post-natal experience, they had minimal social experience, showed little interest and competence with other macaques, were introverted, weren’t agreeable, weren’t conscientious, had high neuroticism and low openness.
Shannon 1998 researched monkeys raised by their mother or raised in a nursery and characterised genes relating to the functioning of serotonin, the short allele version is linked to low resilience of stress. She found that the monkeys with the short allele that were raised in a nursery had lower visual orientation and attention compared to the monkeys with a short allele raised by their mother. Later on in life they showed higher levels of aggression. This study shows gene-environment interactions.
Discuss some evidence for personalities in animals
Part 4: The baboon study
Part 5: Training animals
The measured baboons and 3 personality types; nice, aloof and loner. The nice baboons had more friends, which related to a decrease in their viral load as they had simian immunodeficiency (SIV, like HIV).
You can assess an animals personality to find the ones that are exploratory then you can train them which will reduce their stress during health checks and research protocols like blood samples.
Discuss some evidence for personalities in animals
Part 6: Orangutans
Animals with inhibited personalities have deficiencies in social abilities. For example, an orangutan’s personality correlates with a subjective measure of well being.
Discuss some evidence for personalities in animals
Part 7: Domestic cats
Natoli 2005: 3 groups of cats were observed for aggression, submission, affiliation, territorial display and mating behaviour. Some cats are proactive; higher aggression, more territorial and reproductive, more reproductive success but have a higher chance of getting feline HIV whereas some are reactive; submissive.
Discuss some evidence for personalities in animals
Part 8: Giant Pandas
Powell 2008, the pandas were introduced to novel objects and their owners completed a questionnaire. Their personality correlates with their socio-sexual performance; shy individuals have a poorer performance. This has important implications for breeding programmes.
