What is Evolutionary Psychology? (4)
- Evolutionary psychology is the study of human behaviour, affect and cognition from an evolutionary perspective
- Using evolutionary theory and related knowledge, such as behavioural ecology, ev bology
- In effect, it means viewing humans as part of the animal kingdom, subject to the same laws of evolution, natural selection, etc.
- This might seem contentious! (but there is really no alternative)
Jean-Baptiste Lamarck (1744-1829) (2)
- The inheritance of acquired characteristics
just by strekking your neck you’ll get longer necks, and your offspring etc.
The inheritance of acquired characteristics - Use and disuse
→ flood: it doesn’t work like this, if you cut the tails of mice the offspring will still have tails.
Name 3 components of natural selection, with examples.
1. Variation Hot, ugly, hair color, size etc 2. Inheritance Some are inharitable, predisposition 3. Selection Advantages → overtime the giraffe has got a long neck
3 components of DNA
- Mixing parental genes (Mendelian genetics)
- Recombination
- Mutation
2 forms of sexual selection
- Inter sexual competition: traits that are passed on because they are good at attracting opposite sex mates
> For example: pretty feathers of birds - Intra sexual competition: traits that are passed on because they are good at winning same sex competitions for mates
> For example, stag fight
Genetic drift (3)
- Mutations
- Founder effects
- Bottle neck effects
Why Neanderthals go extinct?
With the brain capacity as big as us?
Their brain was primarily Visual Compex. So no planning etc.
There’s a theory that their not really extinct but they bred with Homosapians.
Humans with a larger prefrontal cortex could outsmart and outcompete the Neanderthals.
Adaptations
inherited characteristics that are naturally selected because they helped to solve a problem of survival or reproduction
By-products
carried along with adaptions but without function
> Belly button
Noise
Noise: random effects, no function
> Eye color?
5 misunderstandings in Evolutionary Psychology
- Human behaviour is only genetically determined
- Human nature is unchangeable
- Everything is an adaptation
- Adaptations are optimally designed
- It is an adaptation, thus it is good
If you think about the theories of Jean-Baptiste Lamarck (1744-1829), how would you explain what is actually true on Inheritance?
EPIGENETICS
Stress: this is inheritable. Children of mice with stress will have a higher level of stress than mice who didn’t have a scary snake experience.
DNA isn’t your destiny, but experiences are inherited. If a gene is switched on, that sceptibility will be there in the genes of the offspring.
What’s the difference between natural selection and inheritance?
Natural selection:
More species are born than can possible survive
Some have a better change of surviving under varying circumstances
Inheritance: these traits will be passed of to offspring, the whole population will be fitter and better adapted to the environment.
Founder Effects
Small portion of population establishes a new colony and the founders are not genetically representative of the original population
» EG redheads community
Bottle neck effects
The population shrinks, for example because of an earth quack or natural dissaster.
Survivers only carry a subset genes of the original population
