Transcript Language Evolution Notes

human language development
a quick overview
Language Origin
...human brains, have been armed by habits and methods,
mind-tools and information, drawn from millions of other
brains which are not ancestral to [them].
...Comparing our brains anatomically with [any other nonhuman brains] would be almost beside the point,
because our brains are in effect joined together into a
single cognitive system that dwarfs all others. They are
joined by an innovation that has invaded our brains and
no others: language.
[Dennett, D. 1995. p.381]
human language & pre-history
50-35kyr ago
technological & cultural change
symbolism
semantically & syntactically rich Ln by 35kyr
(probably much earlier)
human physiology for language
brain function...
Universal Human Grammar and innate language organ
[Chomsky, N. 1986 & others]
Language Acquisition Device [Searle, J. 1992. & others].
• hard-wired
• overlaps general learning and imprinting mechanisms
• builds syntactic, semantic and word meaning knowledge
into cognitive substrates physiologically housed in some
(possibly distributed) language organ.
human physiology for language
speech...
discrete, digital system using limited set of phonemes
approx 40 phonemes for English
some make big deal of low human larynx position
• allows a diverse set of phonemes
but: choking; infant larynx; developed 2myr-300kyr
and: aquatic apes, minor birds, !Kung & Khosa
human physiology for language
speech perception...
• normal speech 10-15 phonemes / sec
• phonemes smear into each other
• listeners can perceive upto 45 phonemes/sec
(though brain probably hypothesises some)
NB: Morse code operators only recognise 3 tokens/second
clicks repeated 15-20 times/sec is heard as a buzz.
selection pressures
• ie: why language evolved
• issue highly colored by contemporary social beliefs.
NB: social traits, behavioural patterns and cognitive
functionality appear different to simple evolutionary but
subject to the same evolutionary mechanisms
NB2: there is a logic to evolution, eg: rings & flashes – water buck & springbok
task related SPs
• toolmaker "Man the Toolmaker" [K. Oakley in 1949]
• agriculturalist
• hunter gatherer
• defence: man the warmonger
socially driven
Darwinian signal-evolution theory invites us to abandon
traditional assumptions about honest communication and
instead ask questions about competition and co-operation,
selfishness versus altruism, manipulation as opposed to
communication. [Knight, C. 1998b]
...primate intelligence - including our own - originally
evolved to solve the challenges of interacting with one
another. [Cheney et al 1986]
an individual is most in competition with others from its own
species, from the same social group: the extended clan,
smaller coalitions, even its family [Ridley, M. 1993]
socially driven
deceit & negotiation
• interesting primate activity is often concerned with conflicting goals
in a social setting.
• deception requires a Theory of Mind - enhanced by means of
communication refering to actions/events which spatially/temporally
distant.
peer pressure & politics
• chatter replaces grooming, evolves to contain socially relevant infm
& leads to emergence of structure/grammar
gender differences & female co-operation
• pregnancy, childbirth & infant parenting (midwifery & bipedalism)
• controversial gender differences in use & development of Ln
• leads to sexual selection for language
other evidence supports social foundation
other issues
• adaptation or exaptation
• the Baldwin effect
• memetics
• theory of mind
• empathy
• social intelligence