Hassett et al. (2008) Flashcards
Animal ethical guidelines
- Number of animals
- Species and strain
- Housing
- Pain and distress
- Replacement
- Rewards and stimuli
- Procedure
What does the “Nature VS Nurture” debate involve?
Debate involves the extent to which certain aspects of behavior are inherited or learned influences
Nature VS Nurture debate
Nature: Influenced by genetic inheritance or other biological factors
Nurture: Influence of external factors after learned behavior such as life experiences/product of exposure
Aim of the study
To investigate whether toy preferences in monkeys resemble those in children in order to test if sex differences in toy choice is biologically determined by sex
Sample
-rhesus monkeys
-135 (multi-male, multi-female)
-61 females, 21 males as potential subjects
-only 11 males, 23 females included in final sample
-age range: infants –> adults
-14 animals not included in analyses (they were exposed to varying hormonal treatments prenatally)
-lived together for more than 25 years
-Yerkes National Primate Research (enter field station)
-social group has a species-typical multiple matriline social structure
-interactions of 39 newborn (0-3 month) infants weren’t coded due to difficulty in individual identification
Evaluation of sample
STRENGTHS:
-high generalisability
(age range infants to adults)
WEAKNESSES:
-low generalisability (same location)
-more females than males
Housing and food ethics
-monkeys housed in their natural group in 25 x 25m outdoor compounds
-research conducted with NIH Guide for the “Care and Use of Laboratory Animals”
-temperature-controlled indoor quarters
-water was continually available
-animals were fed monkey chow 2x daily
-supplemented ONCE per day with fruits and veggies
-under an environmental enrichment
-management protocols of the Yerkes National Primate Research Center approved by Emroy’s Institutional Animal Care and Use Committee
Research method
-field experiment: normal outdoor housing area, free to interact with the toys or not)
-independent measures design
-IV: gender is male/female
-DV: collection of toys
-collection of data: observational technique
-independent measures comparison: monkeys with children
-correlation:
–> co-variable 1 - rank of monkeys (hierarchy)
–> co-variable 2 - frequency/duration of activities with each type of toys
Procedure 1
- 7 25 min trials conducted within large indoor/outdoor enclosure that housed social group
- Prior to each trial, subjects and other social group members were kept indoors while 1 wheeled and 1 plush toy (separated by 10m) were placed in outdoor living area, with left/right placement location counterbalanced across trials
- Monkeys were released in outdoor area
- Each toy + animal interacting with it was videotaped using separate cameras for each toy
- After each trial, toys were removed from outdoor area
- Plush toys torn into multiple pieces, ending trial 7 mins early
Procedure 2
- Identity of animal interacting with toys & behavior towards toys were coded from video tapes by 2 observers working together to achieve agreement on identity & behavior
- Data entered on palm pilots and handobs
(a program designed to enter time stamped behavioral info) - Individuals’ social rank & age were included as variables in analyses
- Rank was assessed in group through extensive behavioral observations:
-grooming
-dominance
-submission behavior
Data analysis
-subjects with fewer than 5 total behaviors:
–> 3 males, 14 fems
–> excluded from analyses
-final N = 23 fem, 11 males
-subjects participated in different no. of trials
-behaviors that were continuous:
–> onsets and offsets were recorded to get durations of those behaviors
-raw frequencies & durations were divided by no. of trials for each subject
-provide average frequency/duration of each behavior for pps
-total frequencies & total durations (for each animal):
–>summing calculated averages for each individual behavior
RESULT 1 - Total Frequency
- total frequency = significant interaction between toy type and sex
- males preferred wheeled (9.77) over plush (2.06)
- females showed no significant preference for plush (7.97) over wheeled (6.96)
- males and females did NOT differ in total interactions with wheeled toys
- males interacted significantly less with plush toys than did females
RESULT 2 - Total Duration
- total duration = interaction between toy type and sex
- males interacted for greater total time with wheeled (4.76 mins) than with plush toys (0.53 mins)
- females did NOT differ in duration of interactions with toy type (wheeled = 1.27 mins) and (plush = 1.49 mins)
- males and females did NOT differ significantly in total time spent with wheeled or plush objects
Overall results
- males showed significantly higher preference for “masculine” (wheeled) toys than did females for “feminine” (plush) toys
- significant sex difference of preference revealed for frequency:
–> males = 7.71
–> females = 1.00 - duration:
–> males = 4.23
–> females = 0.22
RESULT 3 - Ranks of Rhesus Monkeys
- mean rank between males (9.3) and females (8.7) revealed no significant differences
- interaction between toy type and rank was NOT significant
- SPEARMAN’S CORRELATION:
Both sexes combined = rank + total frequency positively correlated for both plush and wheeled toys - MALES: plush and wheeled toy total frequencies and duration did NOT correlate significantly
- FEMALES: rank positively correlated with total frequency and duration with plush and wheeled toys
