Outline 9/22/98

Biopsychology

Proximal & Distal Causes

The Theory of Evolution

Overview of theory and natural selection

Evolution and brain structure

Evolution and human behavior

Evolution and Emotion

Evolution and Mate Selection

Men and Beauty

Women and Status

Evolution and Determinism

 

 


Evolution and Behavior

 


Biological Approaches to Behavior

Proximal Cause--The immediate cause. In terms of biopsychology--current physiological structure and changes.

 

Distal Cause--The remote cause. In terms of biopsychology--evolutionary explanations.

 

 


Charles Darwin

 

 


H. M. S. Beagle

 

 


Natural Selection

 

Any inherited characteristics that increase the likelihood of survival and reproduction are selected for, and any that decrease the likelihood are selected against

Goldstein, 1994

 

 

 


Four Assumptions of Evolution

Members of a species have characteristics that vary (e.g., beak size in birds).

 

At least some of these characteristics are passed on genetically.

 

Some of these variable characteristics will aid survival (e.g., a tough beak on nutty island)

 

Species produce more offspring than survive to be adults (i.e., some organisms die before procreating).

 

 


Brains across species

 

 


Evolution and Human Behavior: Emotions

 

 


Darwin argues emotions serve communication function

 

 


Facial neuromuscular mechanisms show continuity from higher primates to man.

 

 


Facial expressions in humans bear close similarity to animal responses that originally served a function relating to defense.

 


Some facial expressions closely resemble reflexive reactions to nonsocial stimuli (e.g., foul odor).

 

 


Ekman

 

 

 


Evolution and Human Behavior: Gender differences & romance

When it comes to romantic partners:

men seem to focus on physical beauty

women seem to focus on status

 

 


Kenrick, Gutierres, and Goldberg, 1989

What they did:

Show heterosexual men and women either opposite sex nudes or abstract art.

Then have everyone rate their satisfaction with their current romantic partner.

What they found:

Women were unaffected by the manipulation.

Men were more dissatisfied with their current partner after looking at nudes.

Conclusion:

Men are more affected by physical beauty than are females

 

 

 


Kenrick, 1992

What he did:

Set up a "dating game." Manipulated physical attractiveness and status of prospective dates.

What he found:

Men were attuned to physical attractiveness, but not status. Women were attuned to status, but not physical attractiveness.

 

 

 

 

 

 


Buss & Schmitt

 

 

 


So how do we turn this difference into an evolutionary account?

 

 

 


An Evolutionary account of men's focus on physical beauty

 

 

 

 


An Evolutionary account of women's focus on status

 

 

 

 

 


A Slightly Different Gender Difference

What Buss did:

Asked men and women to imagine that their romantic partner was engaged in either a physical or emotional relationship with someone else.

Then asked them to indicate how "upset" they would be.

What he found:

Women were more upset imagining emotional relationship.

Men were more upset imagining physical relationship.

 

 

 

 

 


But what is beauty?

Is beauty defined by evolution or by culture?