18th January 2011
Psych 178 – Lecture 5
The Person as a Machine – mechanical/physical sciences.
Sociobiology – Personal Experience
The theory is much better at the subhuman level because there are many phenomena which are contrary to
the sexual survival theory: homosexuality, suicide, declining birth rates…
•The deceit for men is that they are more caring than they actually are and women’s deceit is that “sexual
favours will come later”
•One girl’s parents found out her brother was homosexual and started giving her all the resources so that
she can have children and pass on the genes.
oWhy homosexuality has survived has been theorized to be due to the fact that the gene for
homosexuality is connected to a gene that provides protection against some illness – like sickle cell
•Grandparents are more likely to try to have more children if they have a lot of daughters.
•Hugh Hefner marrying the 24 year old – makes sense socioblologically because he is a wealthy high status
Ultimate determinant of behaviour – genetic survival (distal)
•We eat so we can survive and then reproduce.
•We go to school, get a good job (more resources), attract a mate and then reproduce.
There is no real proof for this but there are many inferences from observations of behaviour.
Physical Sciences – Proximal Determinants of Behaviour
•How much do you eat?
•How do you predict a grade point average?
•What do you have to know to predict whether a person will go eat?
oHow good of a friend they are/nature of relationship
oHow good the food is/food quality
oActivity in progress/alternatives (what he is already doing)/Prior plans
oCost/Who is paying?
•First separate the determinants of behaviour and then calculate their influence mathematically.
oMotivation = hunger x incentive –(cost + other plans)
oMotivation = a x b – (c + d)
Spinach vs. Ice Cream
•Children are expected to run 3 miles an hour for spinach if they have not eaten for 3 hours.
•Children are expected to run 10 miles an hour for spinach if they have not eaten for 9 hours.
•Children are expected to run 13 miles an hour for ice cream if they have not eaten for 3 hours.
•Children are expected to run 19 miles an hour for ice cream if they have not eaten for 9 hours.
oTo see if hunger makes a difference, average the speed for 3 hours and 9 hours: 8 miles an hour (3
hours) and 14.5 miles an hour (9 hours)
oIf incentive makes a difference, children will run faster for ice cream: 6.5 miles/hour (spinach) and
16 miles/hour (ice cream)