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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
Co-evolution can also occur in situations where one organism is parasitic on another
    • bacteria specialize to invade other species, which in turn evolve defenses
    • consider case of malaria, which may account for the persistence of the sickle-cell gene in some human populations
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

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?
  • 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)
  • 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)
  • 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)
  • 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
  • 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