Universal darwinism
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Universal Darwinism?. We know that biological evolution requires replication with variation , plus natural selection for useful traits But Dawkins suggests that evolution will ALWAYS happen when these preconditions are met This evolution might not be biological!. Breeding ideas?.

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Universal darwinism
Universal Darwinism?

  • We know that biological evolution requiresreplication with variation, plus natural selection for useful traits

  • But Dawkins suggests that evolution will ALWAYS happen when these preconditions are met

  • This evolution might not be biological!

Breeding ideas
Breeding ideas?

  • It may seem silly to think of an idea, or a form of behaviour, breeding…

    • BUT breeding = creating a new copy

    • Whenever an idea is spread to another mind, a new copy of the information in that idea is created

  • … so we can say that whenever someone hears a new idea or learns a new behaviour, that idea has successfully reproduced

How do ideas reproduce
How do ideas reproduce?

  • Imitation

    • Animals very bad at this

    • Humans very good at this

  • We readily imitate the behaviours of others

    • Linguistic behaviours

    • Fashions, hobbies, crazes

The evolution of culture
The evolution of culture

  • So ideas reproduce (with variation) …

    • Are ideas selected?

    • Yes!

  • What ideas will get selected?

    • i.e. What ideas will tend to spread?

    • Ideas which are good at spreading themselves!

Enter the meme
Enter the meme

  • Dawkins in The Selfish Gene:

    • “meme” as the unit of imitation

    • (just as “gene” is the unit of biological inheritance)

    • suggested that memes can evolve

    • groups of memes making up “idea animals”

  • Theory elaborated by Blackmore (1999) and others (e.g. the philosopher Dennett)

  • Key point: memes are selected for their usefulness to themselves, not to us!

  • Memes as parasites?

What is co evolution
What is co-evolution?

  • As we have seen, species evolve by natural selection to fit their environment…

  • … but part of that environment may be other organisms!

  • Organisms can evolve to become dependent on one another (symbiosis)

Co evolution in nature
Co-evolution in nature

  • Intestinal bacteria

  • Insects pollinating flowers

  • The eukaryotic cell

  • … and many other examples

  • We might also consider co-evolution of different genes, at separate loci, within a single species

  • For example, consider the stick insect, where genes that lead to the development of a body appearance that resembles a twig co-evolve with genes that lead to behavior that reinforces the camouflage

Language as co evolution

Language as co-evolution separate loci, within a single species

Deacon and Blackmore

In this case we will consider co-evolution between genes and memes within a single species, rather than co-evolution between two species

What has this got to do with language
What has this got to do with language? separate loci, within a single species

  • If we put these two ideas together…

  • … we can see language as a bundle of behaviours, an “idea animal”

    • Its habitat is the human brain

    • It has evolved to fit that habitat

  • Can we explain the origin and / or acquisition of language in these terms?

Blackmore 1999
Blackmore (1999) separate loci, within a single species

  • Blackmore on the Big Brain: it evolved to allow us to store and spread memes better

  • Blackmore on the origin of language:

    • What is language for? – she concludes it is for spreading memes

  • Co-evolution:

    • language (made of memes) is evolving…

    • But our genes are evolving to fit our memes (inc. language) too

Deacon 1997
Deacon (1997) separate loci, within a single species

  • Deacon: key to language is symbol use

    • Control of social/sexual relationships

  • Language evolves to fit its environment

    • Its environment is the brain of the child

  • Language has therefore evolved to become easy for a child to learn

    • Deacon: this explains language acquisition

  • Our brains have also evolved to accommodate language (co-evolution)

Summary separate loci, within a single species

  • Two theories based on language evolving to inhabit us, rather than us evolving to use language

    • Blackmore: meme theory

    • Deacon: language evolving to fit child’s brain

  • Both theories involve co-evolution

    • Language and brain/body have evolved together, becoming co-dependent/symbiotic

Word of warning
Word of warning separate loci, within a single species

  • Both Deacon and Blackmore’s theories are relatively new…

    • … and fairly controversial

  • They are only favoured by a minority of linguists

  • e.g. the Chomskyans oppose this view