Gene’s-eye-view perspective
genes build individuals in order to replicate themselves.
One way to understand adaptation
genes that act as if they’re trying to replicate copies of themselves by building individuals that would then survive and reproduce.
Examples of fitness maximisation prediction often fails profoundly in modern env’s.
- Wealthier people are actually having fewer offspring.
- No extreme competition to donate to sperm banks. - difficult to get men to do this.
- Non-reproductive sex is common (e.g. contraception, pornography).
- Many people choose not to have children.
- Various forms of self-destructive behaviour (addictions, unhealthy eating habits, etc). - not good for survival or reproduction.
Problem of avoiding incest
you are likely to share recessive mutations with your relatives, which are more likely to express in your child. - Inbreeding depression leads to genetic conditions that can be detrimental.
Adaptations are functionally specialised
An adaptation’s role in solving an adaptive problem is known as its function
What is the Westermarck Effect?
‘If I grew up in the same household, suppress sexual attraction’.
What is adaptive lag.
the more rapidly a species’ env changes, the more frequently its adaptations will tend to misfire.
What is mismatch
Lack between the adaptations we have and the current env we live in
Taste preferences for hard-to-acquire, essential nutrients. - Nesse & William
We have these preferences for foods that end up being bad for us and make us die early, (could be considered maladaptive) These foods used to be hard to acquire, this psychologically requires you to have a strong motivation (don’t have strong preferences for foods such as root vegetables because they have always been easily accessible)
what outcomes can adaptive lag have?
maladaptive outcomes, including physical and mental illness.
‘Humans are ancestral-environment fitness-cue maximisers’ - Tooby & Cosmides
If a cue was there ancestrally that led you to this adaptive behaviour, then you’re going to respond to that cue in the modern environment too
Tooby & Cosmides main point.
“Humans are adaptation-executors, not fitness-strivers”
‘Environments of evolutionary adaptedness’ invented by who?
Bowlby (1969) in considering origins of infant attachment styles.
EEA does not refer to a single, specific time or place
each adaptation has its own EEA: the set of environments that ‘designed’ it.
Some adaptations have more recent EEA than others, e.g. language more recents than eyes.
Which EEA is regarded as most relevant to human EP?
Pleistocene hunter-gatherer environments (2.6 million-12 thousand years ago). - most of our adaptations probably emerged during this period of time.
Egalitarian
believing in or based on the principle that all people are equal and deserve equal rights and opportunities.
Example of rats being picky
Rats are highly selective (more so than humans): eat new foods separately, and only avoid new foods after becoming sick.
What does disgust do?
- It keeps us from ingesting harmful bacteria.
- It is a defence against microbial attack; germs, diseases, viruses.
- Women experience more (A) disgust toward disease-carrying objects, and (b), perception of disease risk. (Curtis et al., 2004).
- Believed to be an adaptation because when they are pregnant, it is a way of protecting the foetus.
- Increased disgust sensitivity is associated in modern populations with having fewer infections
How disgust (adaptations) can be repurposed and perform functions in other domains.
sexual disgust whith the idea of being with someone they do not wnat to mate with.
There is also moral disgust - when you see shocking beh.
Spices are hypothesised to be another antimicrobial defence
- Spices kill food-borne bacteria.
- More common in hot climates, in meat dishes.
What is the hypothesised function of pregnancy sickness?
Adaptation to protect foetus from toxins (teratogens).
The Hunting Hypothesis
- Hunting played a central role in the emergence of modern humans.
- Meat provides unique nutrients and an exceptionally dense package of calories.
- Good for our metabolically costly brains (2% of body mass, 20% of energy). - one way to get this was through hunting.
- cognitive niche
‘cognitive niche’
developing new, innovative ways to exploit resources.
- Tooby
§How are humans adapted for eating meat
- Human teeth, digestive systems are adapted for meat digestion (e.g. very long, small intestines for breaking down proteins.
- Hunter-gatherers spend huge amounts of time hunting
