evolutionary explanations for behaviour

Question 1

introduction

Answer 1

A behaviour that can be explained by evolution is disgust sensitivity as it explains survival of the fittest and natural selection

Question 2

STUDY 1

Answer 2

curtis, aunger and rabie

Question 3

aim

Answer 3

to investigate whether disgust sensitivity evolved as a protection from risk of disease

Question 4

Procedure

Answer 4

+ 40,000 people from 165 countries were used
+ a survey on the BBC website was put up and was advertised in a BBC documentary
+ respondents were asked a set of demographic questions
on their age,sex, country etc
+ they were made to look at 20 photos, 14 of which were paired (7 pairs) into disease-salient stimuli and less disease salient stimuli
+ they were made to rathe the images for disgust on a scale of 1 to 5 (1 = least disgusting and 5= most disgusting )
+disease salient stimuli included blood, urine (bodily fluids)
e.g a cloth with a redish yellow stain vs a blue stain
+they were asked who they were most likely to share a toothbrush with

Question 5

results

Answer 5

response to toothbrush question–> least postman, boss,weatherman,sibling, best friend, spouse most likely

disease salient had higher disgust rathing than less-salient stimuli
(plate with organic looking fluid was rater 61% more disgusting than plate with blue fluid )

results were consistent across cultures
females rated more disgusting than men
age-based decline in disgust sensitivity

Question 6

conclusion

Answer 6

all 5 tests supported the evolutionary explanation of disgust sensitivity as a response that reduces risk of disease

Question 7

evaluation

Answer 7

neuroplasticity contradicts this idea
assumptions were made for function
high testability

Question 8

STUDY 2

Answer 8

Fessler et al

Question 9

aim

Answer 9

to investigate whether disgust sensitivity is adjusted as a function of the immune system, by testing the hypothesis that disgust sensitivity varies across pregnancy in a manner that compensates for changes in the vulnerability to disease

Question 10

procedure

Answer 10

Using a web-based survey of 496 pregnant women, with an average age of 28 years old, the researchers compared the disgust sensitivity of participants in their first trimester with those in later stages of pregnancy. 155 participants were in the first trimester, 183 in the second trimester and 158 in the third trimester. Responses from women who were in the second and third trimesters at the time of participation were pooled and compared with the responses from women who were in the first trimester.

Question 11

results

Answer 11

Analysis revealed that participants in the first trimester reported greater overall disgust sensitivity than did participants in the second and third trimesters, and they also experienced more nausea. A simple correlational analysis revealed that overall disgust sensitivity was positively related to the current level of nausea throughout pregnancy.

Question 12

conclusion

Answer 12

These results provide support for the hypothesis that disgust sensitivity varies during pregnancy in a manner that compensates for maternal and foetal vulnerability to disease.

Question 13

evaluation

Answer 13

Self-report studies, especially a written questionnaire conducted online, are not the best ways to gain valid responses, as people often approach them thoughtlessly and in a hurry.

Question 14

evaluation

Answer 14

Self-report studies, especially a written questionnaire conducted online, are not the best ways to gain valid responses, as people often approach them thoughtlessly and in a hurry.