Evolutionary psychology 2026
Evolutionary psychology: human mind has been shaped by evolutionary processes →
generate and test hypotheses about human psychology and behaviour. Human
behaviour = evolved psychological mechanisms x individual development, culture
and current environments.
- does not imply genetic determinism (genes determine behavior), inevitable,
unchangeable, or morally desirable behavior (modern food industry (evo
mismatch)) or that every behaviour is an adaptation → evolutionary does not
equal is optimal designed
- not always for the good of the species → just concerns differential rep
success between individuals
- viewing humans as part of the animal kingdom, subject to the same laws of evolution,
natural selection, etc
- = scientific, in comparison to creationism and seeding theory
- Evolution: changes in gene (allele) frequency within a population over generations
Lecture 1: Foundations (chapter 1+2)
Why do we need evolution to understand human psychology?
→ To understand human psychology fully, we need to know both how psychological
mechanisms operate and why natural and sexual selection shaped them in the first
place.
Learning goals:
Be able to articulate what is evolutionary psychology
Be able to identify the three essential ingredients of evolution via natural selection
Understand the difference between natural and sexual selection
Be able to identify why Neanderthals went extinct
Know the history of evolutionary psychology
Be able to list procedures for identifying adaptive problems
Be able to identify common misunderstandings about evolutionary theory and evolutionary
psychology
questions can be answered in two (complementary) ways (Timbergens's distinction):
1. proximate answer: biological trait/behavior in an individual
2. ultimate answer: explains why trait evolved through nat selection: so why does it help
your rep success)→evo lens required to answer ultimate questions of human
psych
Important figures in the evo psych
- Jean-Baptistic Lamarck: first to use the word ‘biology’
- two major causes of species change over time: (1) internal tendency for species
to progress toward a higher form (2) the inheritance of acquired characteristics
1. Use and disuse of traits: try hard in the gym → kids will be more
muscular + Giraffes get longer neck over gens by stretching it to reach
leaves (incorrect)
,Evolutionary psychology 2026
2. The come-back kid: Epi-genetics: certain things have effect on gene expression
(so not the genes itself, just tags on DNA that determine if it will be turned on/off)
- Darwin’s theory of Natural selection: causal process how species change over time
- ‘’As many more individuals of each species are born than can survive;
and there is a struggle for existence → due to variation some will have
a better chance of surviving, and thus be naturally selected. From the
strong principle of inheritance, any selected variety will tend to
propagate its new and modified form’’
- Especially strong early in life: child diseases earlier exterminated than cancer
- evolution by selection is the only causal process capable of producing
the fundamental adaptive components of human nature → all
psychological theories rely on evolutionary assumptions about our
species' underlying nature
- Three components for natural selection
1. Variation: organisms vary = the raw materials of evolution
2. Inheritance: the reliable passing of traits down generations
a. Darwin originally did not understand how inheritance worked.
Gregor Mendel: discovered the mechanisms of heredity through
cross-breeding of peas ‘’inheritance is particulate, meaning
genetic qualities are passed distinct packets called genes’’
3. Selection: differential reproductive success → organisms with
favorable inherited variations out-reproduce others
People implying Darwin:
- Sigmund Freud: “sex is important!” (sex cells = Gemete)
- Freud was significantly influenced by Darwin’s work
- misinterpreted Darwin to some extend
- William James: “we have lots of instincts!”
- The mind evolved because adaptive mental processes helped humans survive,
meet environmental demands, and reproduce.
- argued against his contemporaries (who believed human instincts were few and
restricted only to early youth and sex) by claiming that humans have a massive
number of highly specific, evolved instincts
- believed instincts were not automated, rigid behaviors; they could be modified by
experience or overridden by other instincts
- Skinner’s Behaviorism: “anything can be learned as long as it is rewarded!”
- some things can be learned more easily than others
- Harry Harlow’s Monkeys: Using behaviorist operant conditioning, skinner predicted infant
monkeys would attach to a wire "mother" because of the food. but, they preferred
"mother" that provided contact comfort even when she provided no food
- the baby instinct to seek intimacy was greater than the instinct for food
- The Garcia Effect: rats are evolutionarily preprogrammed to learn food aversions in a
single trial, even when the sickness occurs up to 24 hours after ingestion. Crucially, rats
could not be conditioned to associate nausea with visual (light) or auditory (sound) cues.
,Evolutionary psychology 2026
- Wilson: ‘’genes hold culture’; human culture is shaped by our biological nature
- Richard Dawkins: organisms are bodies for the transfers into the next generation
- so only reproduction gene is what matters, not you
- Cosmides and Tooby: used a swiss knife as metaphor for the human mind (flexible)
- Sarah Hardy: focusses on woman, maternal instincts
Difference between natural and sexual selection
- Natural selection drives survival by favoring traits throughout GENES that help an
organism live in its environment, while sexual selection drives reproduction by favoring
traits that help an organism find or win a mate
Two forms of sexual selection
1. Via Inter-sexual competition: traits that are passed on because they are good at
attracting opposite sex mates (pretty feathers of birds)
2. Via Intra-sexual competition: traits that are passed on because they are good at winning
same sex competitions for mates (antlers of stags (male deer))
a. sexual selection stronger for men because of greater variability in reproduction
Six procedures for identifying adaptive problems
1. Guidance From Modern Evolutionary Theory: directly or indirectly influence reproduction
2. Guidance From Knowledge of Universal Human Structures: Because almost all humans
(excluding hermit) live in groups, universal human social structures serve as a map for
identifying adaptive problems
3. Guidance From Traditional Societies: studying modern-day traditional societies provides
incredibly accurate clues about the selective pressures our ancestors faced
4. Guidance From Paleoarcheology and Paleoanthropology: Analyzing physical remains—
such as stones, ancient tools, and bones—provides direct, fossilized evidence of
ancestral survival hazards
5. Guidance From Current Mechanisms: modern psychological architecture acts as a
"window" to view the problems of our evolutionary past Current human phobias and
emotions reflect ancestral hazards rather than modern ones
6. Guidance From Task Analysis:
, Evolutionary psychology 2026
Lecture 2: Adaptations for survival (chapter 2 +3)
Learning goals
Understand the difference between ultimate evolutionary explanations (why) and proximate
explanations (how/what) for behavior
List methods for testing evolutionary psychology hypotheses
Compare the hunting and gathering hypothesis for food provisioning
List the most common human survival emotions and their adaptive function
How did survival problems shape the human mind and Psychology?
Natural selection favored psychological mechanisms that helped humans detect opportunities
and threats and respond adaptively to recurrent survival problems (finding food, avoiding
predators, and dangerous environments)
Evolution through natural selection generates multiple products
1. adaption: inherited traits that helps solve problems of survival or reproduction
a. serves an evolutionary purpose!!
b. ie food preferences
2. by products: carried along with adaption but without evolutionary function
a. ie male nipples
3. noise: random effects, no function
a. ie belly button variation
4. Mismatches: used to be adaptive, but not anymore
a. turtles using moonlight to navigate, modern food industry
evolved psychological mechanisms: if-then mechanisms (mental algorithms)
- ie: threat-detection mechanisms: solves a problem related to survival
- takes inputs → transforms in adaptive outputs, for example:
- psychical (wide eyes), psychological (fear). behavioural (running away)
- our threat system works in a better safe than sorry way → can be the cause
for anxiety (‘’smoke detection system'’ also recognizes egg smoke)
How to generate and test evolutionary psychology hypotheses?
- Two strategies:
1. top down: start with theory → hypothesis (deduction)
a. kin selection theory: favour bio children over non-bio children
2. bottom-up: explain observation with theory (induction)
- testing prediction that rolls out of a hypothesis
- field study: observe irl, lab study: participants, cultural study: across countries
- research methods
1. psychological experiments
2. cross cultural anthropological studies: tests universal adaptations
3. psychological and neuroscience measures: fMRI
4. comparative research: ie comparing different species
Evolutionary psychology: human mind has been shaped by evolutionary processes →
generate and test hypotheses about human psychology and behaviour. Human
behaviour = evolved psychological mechanisms x individual development, culture
and current environments.
- does not imply genetic determinism (genes determine behavior), inevitable,
unchangeable, or morally desirable behavior (modern food industry (evo
mismatch)) or that every behaviour is an adaptation → evolutionary does not
equal is optimal designed
- not always for the good of the species → just concerns differential rep
success between individuals
- viewing humans as part of the animal kingdom, subject to the same laws of evolution,
natural selection, etc
- = scientific, in comparison to creationism and seeding theory
- Evolution: changes in gene (allele) frequency within a population over generations
Lecture 1: Foundations (chapter 1+2)
Why do we need evolution to understand human psychology?
→ To understand human psychology fully, we need to know both how psychological
mechanisms operate and why natural and sexual selection shaped them in the first
place.
Learning goals:
Be able to articulate what is evolutionary psychology
Be able to identify the three essential ingredients of evolution via natural selection
Understand the difference between natural and sexual selection
Be able to identify why Neanderthals went extinct
Know the history of evolutionary psychology
Be able to list procedures for identifying adaptive problems
Be able to identify common misunderstandings about evolutionary theory and evolutionary
psychology
questions can be answered in two (complementary) ways (Timbergens's distinction):
1. proximate answer: biological trait/behavior in an individual
2. ultimate answer: explains why trait evolved through nat selection: so why does it help
your rep success)→evo lens required to answer ultimate questions of human
psych
Important figures in the evo psych
- Jean-Baptistic Lamarck: first to use the word ‘biology’
- two major causes of species change over time: (1) internal tendency for species
to progress toward a higher form (2) the inheritance of acquired characteristics
1. Use and disuse of traits: try hard in the gym → kids will be more
muscular + Giraffes get longer neck over gens by stretching it to reach
leaves (incorrect)
,Evolutionary psychology 2026
2. The come-back kid: Epi-genetics: certain things have effect on gene expression
(so not the genes itself, just tags on DNA that determine if it will be turned on/off)
- Darwin’s theory of Natural selection: causal process how species change over time
- ‘’As many more individuals of each species are born than can survive;
and there is a struggle for existence → due to variation some will have
a better chance of surviving, and thus be naturally selected. From the
strong principle of inheritance, any selected variety will tend to
propagate its new and modified form’’
- Especially strong early in life: child diseases earlier exterminated than cancer
- evolution by selection is the only causal process capable of producing
the fundamental adaptive components of human nature → all
psychological theories rely on evolutionary assumptions about our
species' underlying nature
- Three components for natural selection
1. Variation: organisms vary = the raw materials of evolution
2. Inheritance: the reliable passing of traits down generations
a. Darwin originally did not understand how inheritance worked.
Gregor Mendel: discovered the mechanisms of heredity through
cross-breeding of peas ‘’inheritance is particulate, meaning
genetic qualities are passed distinct packets called genes’’
3. Selection: differential reproductive success → organisms with
favorable inherited variations out-reproduce others
People implying Darwin:
- Sigmund Freud: “sex is important!” (sex cells = Gemete)
- Freud was significantly influenced by Darwin’s work
- misinterpreted Darwin to some extend
- William James: “we have lots of instincts!”
- The mind evolved because adaptive mental processes helped humans survive,
meet environmental demands, and reproduce.
- argued against his contemporaries (who believed human instincts were few and
restricted only to early youth and sex) by claiming that humans have a massive
number of highly specific, evolved instincts
- believed instincts were not automated, rigid behaviors; they could be modified by
experience or overridden by other instincts
- Skinner’s Behaviorism: “anything can be learned as long as it is rewarded!”
- some things can be learned more easily than others
- Harry Harlow’s Monkeys: Using behaviorist operant conditioning, skinner predicted infant
monkeys would attach to a wire "mother" because of the food. but, they preferred
"mother" that provided contact comfort even when she provided no food
- the baby instinct to seek intimacy was greater than the instinct for food
- The Garcia Effect: rats are evolutionarily preprogrammed to learn food aversions in a
single trial, even when the sickness occurs up to 24 hours after ingestion. Crucially, rats
could not be conditioned to associate nausea with visual (light) or auditory (sound) cues.
,Evolutionary psychology 2026
- Wilson: ‘’genes hold culture’; human culture is shaped by our biological nature
- Richard Dawkins: organisms are bodies for the transfers into the next generation
- so only reproduction gene is what matters, not you
- Cosmides and Tooby: used a swiss knife as metaphor for the human mind (flexible)
- Sarah Hardy: focusses on woman, maternal instincts
Difference between natural and sexual selection
- Natural selection drives survival by favoring traits throughout GENES that help an
organism live in its environment, while sexual selection drives reproduction by favoring
traits that help an organism find or win a mate
Two forms of sexual selection
1. Via Inter-sexual competition: traits that are passed on because they are good at
attracting opposite sex mates (pretty feathers of birds)
2. Via Intra-sexual competition: traits that are passed on because they are good at winning
same sex competitions for mates (antlers of stags (male deer))
a. sexual selection stronger for men because of greater variability in reproduction
Six procedures for identifying adaptive problems
1. Guidance From Modern Evolutionary Theory: directly or indirectly influence reproduction
2. Guidance From Knowledge of Universal Human Structures: Because almost all humans
(excluding hermit) live in groups, universal human social structures serve as a map for
identifying adaptive problems
3. Guidance From Traditional Societies: studying modern-day traditional societies provides
incredibly accurate clues about the selective pressures our ancestors faced
4. Guidance From Paleoarcheology and Paleoanthropology: Analyzing physical remains—
such as stones, ancient tools, and bones—provides direct, fossilized evidence of
ancestral survival hazards
5. Guidance From Current Mechanisms: modern psychological architecture acts as a
"window" to view the problems of our evolutionary past Current human phobias and
emotions reflect ancestral hazards rather than modern ones
6. Guidance From Task Analysis:
, Evolutionary psychology 2026
Lecture 2: Adaptations for survival (chapter 2 +3)
Learning goals
Understand the difference between ultimate evolutionary explanations (why) and proximate
explanations (how/what) for behavior
List methods for testing evolutionary psychology hypotheses
Compare the hunting and gathering hypothesis for food provisioning
List the most common human survival emotions and their adaptive function
How did survival problems shape the human mind and Psychology?
Natural selection favored psychological mechanisms that helped humans detect opportunities
and threats and respond adaptively to recurrent survival problems (finding food, avoiding
predators, and dangerous environments)
Evolution through natural selection generates multiple products
1. adaption: inherited traits that helps solve problems of survival or reproduction
a. serves an evolutionary purpose!!
b. ie food preferences
2. by products: carried along with adaption but without evolutionary function
a. ie male nipples
3. noise: random effects, no function
a. ie belly button variation
4. Mismatches: used to be adaptive, but not anymore
a. turtles using moonlight to navigate, modern food industry
evolved psychological mechanisms: if-then mechanisms (mental algorithms)
- ie: threat-detection mechanisms: solves a problem related to survival
- takes inputs → transforms in adaptive outputs, for example:
- psychical (wide eyes), psychological (fear). behavioural (running away)
- our threat system works in a better safe than sorry way → can be the cause
for anxiety (‘’smoke detection system'’ also recognizes egg smoke)
How to generate and test evolutionary psychology hypotheses?
- Two strategies:
1. top down: start with theory → hypothesis (deduction)
a. kin selection theory: favour bio children over non-bio children
2. bottom-up: explain observation with theory (induction)
- testing prediction that rolls out of a hypothesis
- field study: observe irl, lab study: participants, cultural study: across countries
- research methods
1. psychological experiments
2. cross cultural anthropological studies: tests universal adaptations
3. psychological and neuroscience measures: fMRI
4. comparative research: ie comparing different species
