PSYCH 317: ThThe Tree of Culture

The Great Chain of Being

A view that all living beings are arranged in a fixed, static hierarchy from lower to higher forms

The Great Chain of Being why is it inconsistent with modern evolutionary theory

It assumes a linear, unchanging hierarchy rather than branching evolutionary relationships and diversification

The Tree of Life what does it represent

A branching pattern showing how organisms diversify through descent with modification

The Tree of Life what is meant by “descent with modification”

The process by which descendants inherit traits from ancestors while accumulating changes over time

The Tree of Life what does it suggest about biological diversity

That all diversity ultimately stems from a common ancestor

The Tree of Life vs Great Chain of Being

• The Tree of Life is branching and dynamic

• The Great Chain of Being is linear and static

Phylogenetics

The study of evolutionary relationships among groups of organisms, species, populations, or cultural units

Phylogenetics main goal

To reconstruct patterns of ancestry and relatedness

Darwin & Cultural Evolution How did Darwin connect biological evolution and language

He suggested that languages, like species, could be classified through genealogical relationships and common ancestry

Darwin & Cultural Evolution What did Darwin argue would provide the best classification of languages

A genealogical arrangement showing how human groups and their languages descended from common ancestors

Darwin & Cultural Evolution How did early language trees explain language diversity

By showing languages descending and diverging from a common ancestral language

Unilinear Cultural Evolution

The idea that all societies progress through the same sequence of development stages

Unilinear Cultural Evolution proposed stages

• Primitivism

• Savagery

• Barbarism

• Civilisation

Unilinear Cultural Evolution why is it considered incorrect

It assumes a single pathway of progress and ignores cultural diversification

Unilinear Cultural Evolution which evolutionary model is this more similar to

The Great Chain of Being

Cultural Diversification and Phylogenetics How does a phylogenetic approach view cultural diversification

As a branching process where cultures diversif from common ancestral traditions

Cultural Diversification and Phylogenetics How can phylogenetic trees be constructed for languages

By comparing shared linguistic features such as cognates

• e.g. similar words for basic concepts such as “two” across languages

Building Language Phylogenies How are language phylogenies modeled

By tracking the birth and death of cognates over time

Building Language Phylogenies What can language phylogenies reveal

How cultural groups spread and how closely related they are

Austronesian Language Phylogenies Where can Pacific languages be traced back to

Indigenous languages of Taiwan

Building Language Phylogenies Why is Taiwan important in Austronesian language evolution

It contains the greatest language diversity and the oldest language lineages

Building Language Phylogenies Why does greater diversity in Taiwan support it as the origin of Austronesian languages

Greater diversiy suggests languages have been diverging there for a longer period

Critiques of Cultural Phylogenetics What was Gould’s (1991) main critique of applying phylogenetics to culture

Cultural evolution involves extensive transmission between lineages, unlike biological evolution

Critiques of Cultural Phylogenetics According to Gould, how does biological evolution differ from cultural evolution

• Biological lineages diverge and remain separate

• Cultural lineages can reconnect and exchange info

Critiques of Cultural Phylogenetics What is cultural transmission

The spread of ideas, practices, or knowledge between groups

Critiques of Cultural Phylogenetics Why did Gould argue cultural phylogenies may be unreliable

Because cultural change often involves blending across lineages rather than simple branching

Branching vs Blending What characterises biological evolution in a phylogenetic tree

Branching divergence

Branching vs Blending What characterises cultural evolution

Both branching divergence and blending between groups

Branching vs Blending What does blending mean in cultural evolution

Previously separated cultural groups exchanging ideas, practices, or influences

Branching vs Blending Why is the history of English often used as an example of blending

English has incorporated influences from many languages after divergence

Counterarguments to Gould’s Critique Why is Gould’s view of biological evolution considered oversimplified

Biological evolution can also involve mixing between lineages

Branching vs Blending What is admixture + example

Genetic mixing between previously distinct populations

• interbreeding between neanderthals and homo sapiens

Cultural Phylogeny of Electronic Music What did Youngblood et. al (2021) study

The cultural phylogeny of electronic music genres

Cultural Phylogeny of Electronic Music What was used to estimate cultural relationships in electronic music

The likelihood that artists collaborate with one another

Cultural Phylogeny of Electronic Music What did the study quantify

The amount of within-genre connection vs blending between genres

Cultural Phylogeny of Electronic Music major finding

More connections occurred within genres rather than between genres

Cultural Phylogeny of Electronic Music what do the findings suggest about cultural evolution

Branching patterns may remain important despite opportunities for blending

Uses of Phylogenetics why apply phylogenetics to culture

to understand historical relationships, cultural spread, and patterns of cultural change

Uses of Phylogenetics what major problem can phylogenetics help solve in cultural research

non-independence among societies

Galton’s Problem

The issue that cultures or societies are often historically related and therefore not statistically independent

Galton’s Problem why is it important

statistical analyses assume observations are independent

Galton’s Problem what relationship was observed between GDP and self-expression values

A positive correlation

Galton’s Problem why might the GDP-self-expression correlation be misleading

Closely related societies may share both traits because of common ancestry rather than a causal relationship

• Western European and Anglophone countries

Galton’s Problem what happens to the GDP-self-expression relationship when related countries are accounted for

the correlation may disappear

Phylogenetic Explanation of Correlations what are societies represented as tips on a phylogenetic tree

Because they have historical relationships and common ancestry

Galton’s Problem why are societies not independent data points

they inherit traits from shared ancestors

Galton’s Problem how can a correlation arise purely from shared ancestry

a few trait changes near the base of the tree can be inherited by many descendant societies

Galton’s Problem in phylogenetic analyses, what does a shared ancestor explain

similarities among descendant societies

Galton’s Problem what does the phylogenetic approach allow researchers to distinguish

similarities causes by common ancestry vs genuine causal relationships

What is the central idea of cultural phylogenetics?

Cultural traits can diversify through branching descent, allowing historical relationships to be reconstructed.

What is the biggest criticism of cultural phylogenetics?

Culture can blend across lineages through transmission, unlike a simple branching tree.

What is the major advantage of phylogenetic methods in cultural research?

They control for shared ancestry and help avoid misleading correlations caused by non-independence (Galton's Problem).