lecture 1 Evolution of Humankind
understanding social processes (eg. cooperation, warfare, cultural dynamics)
and knowledge.
Know the temporal order of events. Make your own timeline.
Errata Harari also for the exam.
What is most important in social life?
Most important: having the largest impact on the largest number of people.
→ Culture: all information obtained from others, including the making and
handling of objects.
→ Cooperation: provide a benefit at an effort or cost (e.g. support, trade,
voluntary sex).
→ Conflict: from subtle discrimination to warfare. Often has a long impact.
And then other things such as state formation, democracy, inequality.
How to study all these things in a coherent way?
Evolution and the tree of life.
Evolution traditionally: Darwin and many other contributors.
(1) New genes due to the reproduction of incumbent genes with random
mutations; increase variation.
(2) New individuals enter the environment, compete for scarce resources;
those well-adapted (through genes/learning) are positively selected
(3) Survivors stay, thereby changing the environment wherein the next
generation searches for partners.
Fitness= number of children who make it to adulthood.
Evolution level of detail
● Tree of life has species as elements, not individual organisms- it’s a
coarse-grained image of evolution
● Zooming in yields a fine-grained image of individual organisms with
their unique genes and their interaction, thus forming a dynamic
network. (making children/ eating food).
1
,At the level of the individual: evolution as a dynamic network.
● Food, help from others, etc. increases survival
● Parasites, bite from a predator, conflict, poison decreases survival
● Reproduction, variation, and selection are the consequences of some of
these interactions in the environment. Adaptation means surviving
specific interactions
● The dynamic network approach is more fundamental and precise.
Evolution is not ‘’ survival of the fittest’’, but the survival of networks of
complementary diversity.
Evolution does not mean progress and serves no higher purpose. Things, in
general, do not get better.
It does not yield optimal adaptation because environment changes and trade-
offs.
Mal-adaptations (believing fake news) are as interesting as adaptations.
Genes for skin pigmentation do not influence behavior, and human races do not
exist biologically, only as cultural delusion.
Biology does not explain human society.
Evolution of Culture?
→ Darwin (1871): ‘’ the formation of different languages and of distinct
species, and the proofs that both have been developed through a gradual
process are curiously parallel.’’
So does a tree of culture also exist?
Culture: what are the elements
Cultural element = chunk of information. For example social norms,
knowledge on how to handle technology.
Elements may be material or immaterial.
Culture= those aspects of thought, speech, action (= behavior), and artifacts that
are learned and transmitted.
Cultural evolution: tree-like if coarse-grained; less tree-like if fine-grained.
Cultural evolution as a network: tree-ish network with cross-cutting branches.
Horn example.
2
,Evolution of culture: gaps
● Most culture of the past are unrecorded, but that’s no problem for an
overall understanding of cultural dynamics.
● We can look at the general patterns, e.g. most cultural innovations are
improvements of or complements to existing things.
3-step model cultural evolution
(1a) Cultural innovation: a combination of complementary ideas, possibly from
the longer past, plus a bit of random luck (mutations) to make something new.
Serendipity: random good luck.
(1b) Cultural transmission. Innovation = taking ideas from others and
combining them into something new. transmission= taking ideas from others,
simplified version of (1a).
Elements may be changed during transmission (1a+1b together).
(2) Culture use
● People use ideas and artifacts when interacting with others or with
nature/material objects. Based on these experiences, they keep cultural
elements and discard others - outcompeted by more appealing elements.
● These choices may not be voluntary. e.g. victims of war.
● Some cultural selection through natural selection.
(3) Kept, discarded, and forgotten cultural elements change the social/natural
environment. At the same time: demographic changes. People die/ People are
born.
Differences between genetic and cultural evolution.
3
, Difference between complete package at birth, and acquired over a lifetime.
Genes and culture are two complementary information systems that we use. co-
evolution.
Co-evolution of genes and culture examples:
→ Fire mastered for heat, enabled cooking food, natural selection pressure
towards increasing efficiency shortened our intestines.
→ Cattle kept for meat, the advantage of drinking milk when food was
scarce, selection of lactase tolerance by adults.
→ Rice, alcoholic drinks, selection of Adh gene that breaks off alcohol in the
blood.
Co-evolution of culture and genes
Genetic evolution is not replaced by cultural evolution but speeded up since
agriculture. Genes predispose people to be receptive to culture but rarely
determine adult behavior directly. Exceptions are bodily function: giving
birth/sneezing.
Co-evolution: environment shaped culturally (niche construction) imposes
constraints on and new possibilities for evolution.
Addition to Darwinian evolution when adding cultural effects.
Add to (1a): the sexual selection of partners is culturally influenced.
Add to (2): a culture-driven selection of genes (constructed environment/human
actions) that increase survival (e.g. washing hands) or decrease it (co2 in the
air). Epigenetic changes through interactions with elements of the environment.
Culture in other species: example chimps.
→ Distinguish culture from genes: the behavior of multiple individuals in a
group that does not occur in other groups in a similar environment.
Cooperation in other species usually happens in small family groups. Conflict in
other species: most violence if both territorial and social.
Most important (1a) combination of cultural elements into new elements, (1b)
transmitted from one person to another, (2) culture users interact, keep or toss
4
understanding social processes (eg. cooperation, warfare, cultural dynamics)
and knowledge.
Know the temporal order of events. Make your own timeline.
Errata Harari also for the exam.
What is most important in social life?
Most important: having the largest impact on the largest number of people.
→ Culture: all information obtained from others, including the making and
handling of objects.
→ Cooperation: provide a benefit at an effort or cost (e.g. support, trade,
voluntary sex).
→ Conflict: from subtle discrimination to warfare. Often has a long impact.
And then other things such as state formation, democracy, inequality.
How to study all these things in a coherent way?
Evolution and the tree of life.
Evolution traditionally: Darwin and many other contributors.
(1) New genes due to the reproduction of incumbent genes with random
mutations; increase variation.
(2) New individuals enter the environment, compete for scarce resources;
those well-adapted (through genes/learning) are positively selected
(3) Survivors stay, thereby changing the environment wherein the next
generation searches for partners.
Fitness= number of children who make it to adulthood.
Evolution level of detail
● Tree of life has species as elements, not individual organisms- it’s a
coarse-grained image of evolution
● Zooming in yields a fine-grained image of individual organisms with
their unique genes and their interaction, thus forming a dynamic
network. (making children/ eating food).
1
,At the level of the individual: evolution as a dynamic network.
● Food, help from others, etc. increases survival
● Parasites, bite from a predator, conflict, poison decreases survival
● Reproduction, variation, and selection are the consequences of some of
these interactions in the environment. Adaptation means surviving
specific interactions
● The dynamic network approach is more fundamental and precise.
Evolution is not ‘’ survival of the fittest’’, but the survival of networks of
complementary diversity.
Evolution does not mean progress and serves no higher purpose. Things, in
general, do not get better.
It does not yield optimal adaptation because environment changes and trade-
offs.
Mal-adaptations (believing fake news) are as interesting as adaptations.
Genes for skin pigmentation do not influence behavior, and human races do not
exist biologically, only as cultural delusion.
Biology does not explain human society.
Evolution of Culture?
→ Darwin (1871): ‘’ the formation of different languages and of distinct
species, and the proofs that both have been developed through a gradual
process are curiously parallel.’’
So does a tree of culture also exist?
Culture: what are the elements
Cultural element = chunk of information. For example social norms,
knowledge on how to handle technology.
Elements may be material or immaterial.
Culture= those aspects of thought, speech, action (= behavior), and artifacts that
are learned and transmitted.
Cultural evolution: tree-like if coarse-grained; less tree-like if fine-grained.
Cultural evolution as a network: tree-ish network with cross-cutting branches.
Horn example.
2
,Evolution of culture: gaps
● Most culture of the past are unrecorded, but that’s no problem for an
overall understanding of cultural dynamics.
● We can look at the general patterns, e.g. most cultural innovations are
improvements of or complements to existing things.
3-step model cultural evolution
(1a) Cultural innovation: a combination of complementary ideas, possibly from
the longer past, plus a bit of random luck (mutations) to make something new.
Serendipity: random good luck.
(1b) Cultural transmission. Innovation = taking ideas from others and
combining them into something new. transmission= taking ideas from others,
simplified version of (1a).
Elements may be changed during transmission (1a+1b together).
(2) Culture use
● People use ideas and artifacts when interacting with others or with
nature/material objects. Based on these experiences, they keep cultural
elements and discard others - outcompeted by more appealing elements.
● These choices may not be voluntary. e.g. victims of war.
● Some cultural selection through natural selection.
(3) Kept, discarded, and forgotten cultural elements change the social/natural
environment. At the same time: demographic changes. People die/ People are
born.
Differences between genetic and cultural evolution.
3
, Difference between complete package at birth, and acquired over a lifetime.
Genes and culture are two complementary information systems that we use. co-
evolution.
Co-evolution of genes and culture examples:
→ Fire mastered for heat, enabled cooking food, natural selection pressure
towards increasing efficiency shortened our intestines.
→ Cattle kept for meat, the advantage of drinking milk when food was
scarce, selection of lactase tolerance by adults.
→ Rice, alcoholic drinks, selection of Adh gene that breaks off alcohol in the
blood.
Co-evolution of culture and genes
Genetic evolution is not replaced by cultural evolution but speeded up since
agriculture. Genes predispose people to be receptive to culture but rarely
determine adult behavior directly. Exceptions are bodily function: giving
birth/sneezing.
Co-evolution: environment shaped culturally (niche construction) imposes
constraints on and new possibilities for evolution.
Addition to Darwinian evolution when adding cultural effects.
Add to (1a): the sexual selection of partners is culturally influenced.
Add to (2): a culture-driven selection of genes (constructed environment/human
actions) that increase survival (e.g. washing hands) or decrease it (co2 in the
air). Epigenetic changes through interactions with elements of the environment.
Culture in other species: example chimps.
→ Distinguish culture from genes: the behavior of multiple individuals in a
group that does not occur in other groups in a similar environment.
Cooperation in other species usually happens in small family groups. Conflict in
other species: most violence if both territorial and social.
Most important (1a) combination of cultural elements into new elements, (1b)
transmitted from one person to another, (2) culture users interact, keep or toss
4
