PSYC18 Psychology of Emotion Lecture 3: Emotions and Evolution
What is the Origin of Life?
DEPENDS WHO YOU ASK.
- Christians in 16th Century Europe:
- Special creation. t species are unchanging
- Implies: immutable species t what was here in the past is still here in the same form, there is no
But: fossil record reveals:
1. Species change
2. Speciation t new species now that never existed
3. Extinction t species that existed in the past that no longer exist
E.g., Jean-Baptiste Lamarck (1744-1829)
- French naturalist
o Explained by principle of inheritance of acquired characteristics. t useful modification
to the physical body get translated to their offspring
o e.g., weightlifter t bigger muscles than other babies
o e.g., blind birds t taped the eyes shut on birds, if they have babies their babies would be
- KÀ]PZYsoft heredity, phenotype (physical) vs. genotype (unseen genetic makeup).
o Soft heredity t traits are related to phenotype not to genotype, changes are not made in
Non-Evolutionary Precursors to Darwin
Charles Lyell (1797-1875)
- Principles of Geology:
- Earth older than originally thought
- 100 million yrs not 2000-3000 yrs.
- There is enough time for species change.
Thomas Malthus (1766-1834)
- English political economist
Population growth rate > Food growth rate
- /vÀ]oÇY a struggle for existence.
- Fittest organisms favored. t survival of the fittest
- What determines fitness? t anatomical features, behavioral patterns, emotions can make you
more or less likely to adapt
Darwin and The Voyage of the Beagle
Charles Darwin (1809-1882)
- Voyage of the Beagle (1831-1836)
- KÀ]}vY many different species of birds, within species differences there were a lot of
different beak sizes, suspected it related to their environments
- Results from:
1. Within species competition
o N vs. resources
2. Heritable variations t emotions, behavior, physical
o phenotype tied to genotype
3. Conditions that differentially favor some variations over others t evolution
o e.g. 1, peppered moths - birch trees that have turned black from industrial revolution
o e.g. 2, phototropism t moths that psychologically like light will die t change in behavior
- Making it to sexual maturity = basic survival.
- Sexual prowess = a different thing altogether.
- Self-preservation vs. Self-propagation. t surviving vs. find a mate and reproduce
- Might they interfere?
Given these two pressures we can ask:
- help us survive?
- help us to reproduce?
- help us pass our genes to the next generation?
o ]ÀX]v]]]v]}vZY helping out our brothers and sisters
- To ask this question we presume that emotions serve functions:
o Orienting, organizing (priority), interacting (social bonds).
- The expression of emotions in man and animals (1872)
- He studied his infant son and actors:
o How are emotions expressed in the face?
o What noises do animals make when emotional?
- Æ]}vA(=À}o]Ì]}vvo}Y}Ç~v]}vU}µ+ movements.
Darwin and Emotional Expressions as Adaptations
- Emotional expression: - are not random
o an action that used to directly aid with survival. (and reproductive success)
XPXU[flattened ears; wolves mouthing (get more to eat). t adaptive
o at that time performed in conjunction with felt emotion.
e.g., anger(cat); happiness and gratitude (wolves)
- Emotion used to be tied to an adaptive action, but now action is tied to emotion:
- Emotion expression is an intention movementYsuggests what actions may follow.
o e.g., violence, submission.
- As such, emotional expressions may save organism from carrying out elaborate suite of actions
o Expression is a better survival guarantee.
- ÀvµooÇYÆ]}v}µÀv]v]µ]}vÁZZ]}v]useless or unnecessary...