The Sudden Evolution of Language?
-- Pillar #6
Brian MacWhinney
Psychology
Carnegie Mellon
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Collaborative Commentary - MacWhinney
The Seven Pillars of UG
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Grammar Gene
Speech is Special
Language Organ and Modularity
Critical Periods
Poverty of the Stimulus
Sudden Evolution of Language
Recursion - LND
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Collaborative Commentary - MacWhinney
Data Sources
1. Direct Evidence
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Genetics
Fossils, reconstructions, comparative physiology
Settlement patterns, habitat range
Tools, artifacts, art
Climactic changes - glaciation, eruptions
2. Indirect Evidence
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Human ontogeny, language acquisition
Neurology
Linguistics -- function, gesture, phonology, recursion
Evolutionary Psychology
All of the above across other primates and other species
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Collaborative Commentary - MacWhinney
Core Issues
• Saltation vs. Coevolution
• Developing an account that is consistent with the
observed data
• Recent focus by Hauser, Chomsky, Fitch on recursion as
the core of language
• Can we use this account to predict new findings and
results in:
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Comparative behavior
Comparative neurology
Fossils, tools, settlement, genetics
Evolutionary Neural Networks
Evolutionary Psychology
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Collaborative Commentary - MacWhinney
Lessons from Child Language
Language learning involves linking a series of
abilities
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Audition
Segmentation
Imitation
Articulation, Timing
Attention
Lexicon
Combination
Recursion
….
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Collaborative Commentary - MacWhinney
Lessons from Functional
PsychoLinguistics
• Language is grounded on cognition in
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Direct perception
Space/Time/Aspect deixis
Causal Roles
Social Roles
• Each level is organized by perspective
• Incremental processing starts from embodied
core -- McNeill
• Compilation relies on item-based patterns and
recursion
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Collaborative Commentary - MacWhinney
Lessons from Evolutionary Theory
• Adaptations must lead to individual
reproductive advantage
• Group advantages are secondary
• Advantages can be linked to
disadvantages (sickle cell, autism)
• Populations are dynamic
• Changes are gradual and emergent - but
this is still debated
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Collaborative Commentary - MacWhinney
Skill Network
• Each attainment builds on previous ones.
• Each relies on abilities that are found in a more
limited form in our primate cousins.
• Each ability can in turn be decomposed into
subcomponents.
• Given this, simple saltation is impossible.
• However, some key changes could foster
productive co-evolution of the network.
• What forces could support continued progress?
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Collaborative Commentary - MacWhinney
Continued Support
• The shift to bipedalism continued across
three million years.
• The role of the freed hands changed over
time, but was a continuing drive.
• Social forces exerted continual pressure.
• Social forces combined with the role of the
hands.
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Collaborative Commentary - MacWhinney
A Grounded Social Climber
• As a bipedal, man is like the kangaroo.
• Unlike the kangaroo, hominids were
climbers who used their hands.
• The hands were then used to control tools,
but …
• Forced into face to face contact, the hands
could also contribute to social interaction.
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Collaborative Commentary - MacWhinney
Proto-Mimesis
• Bipedalism opens up face-to-face contact
• The hands operate in the contact area
• This produces proto-mimesis (Zlatev) with
pointing and teaching
• Vocalization locks in attention
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Collaborative Commentary - MacWhinney
Partial Differences
• Some ape lexical learning, but incomplete
• Some ape planning abilities (Goodall
straws), but incomplete
• Some ape intersubjectivity, but incomplete
• Some ape pointing, but incomplete
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Collaborative Commentary - MacWhinney
Sharper Changes
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Cortical control of vocalization
Duality of patterning - Recursion?
Brain expansion
Physical changes
 Articulation - teeth, mouth
 Phonation - vocal cords, bent vocal tract
 Thumb
 Posture, parturition, neotony
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Collaborative Commentary - MacWhinney
Problems with Saltationism
• Only deals with the last 100,000 years, not the
last 6 million years
• Ignores 300% increase in brain size
• Ignores many morphological changes
• Ignores homo erectus expansion.
• Fails to deal with gesture
• Fails to deal with skill network
• Etc…
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Collaborative Commentary - MacWhinney
Five Periods
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Bipedalism
7-4 MYA
Social Cohesion 4-2 MYA
Mimesis
2-.2 MYA
Phonology 300,000 - 50,000
Creativity
50,000 - now
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Collaborative Commentary - MacWhinney
Cognitive Attainments
• Bipedalism
 Basic imagery, tool use, spatial recursion
• Social Cohesion
 Cortical control of vocal-auditory channel
• Mimesis
 Gestural item-based pattern, prosody
• Phonology
 Phonemic system, phonological loop
• Creativity
 Item-based, perspective
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Collaborative Commentary - MacWhinney
1. Bipedalism
• Coppens East Side Story 10-7 MYA
• Jungle -> savannah (lakes?)
 Handedness and affordances for arboreal
 Deixis for terrestrial
• Tool use and locomotion (primary)
• Communication (secondary)
• Groups needed for protection against
predators
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Collaborative Commentary - MacWhinney
Neuronal Support
• Parietal reorganization at 4MYA- Holloway
 Body image projection
 Navigation and deixis
 Spatial images support recursion
 Facial recognition (supramarginal)
• Tools, navigation, social cohesion
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Collaborative Commentary - MacWhinney
2. Social Cohesion
• Expansion at 4MYA, contraction at 3.5MYA
• Habilis/ergaster vs. australopithecus
• Competition was won by the most cohesive and
planful groups
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Good social partners
Sexual arms race
Dominance vs. external aggression
Role of dialect marking
Dunbar, Power, Worden social accounts
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Collaborative Commentary - MacWhinney
Cortical Control of Vocalization
• Primate system links
 Arousal (amygdala, brainstem)
 Motivation (basal ganglion)
 Memory (limbic, hippocampus)
• The primate external striatum was absorbed by
the neocortex, giving cortical control
• Control is now from the supplementary motor
and anterior cingulate
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Collaborative Commentary - MacWhinney
3. Mimesis
• Parallel evolution
 The gestural channel contained the content
 The vocal channel contained the social glue
• Disorganized nature of mimetic processes
• Inefficient gestalt encoding
• Mechanisms:
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Imitation
Pointing
Joint attention (Intersubjectivity)
Perspective-taking
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Collaborative Commentary - MacWhinney
Monkey See, Monkey Do
• Whiten 2003
Patteson 1978
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Collaborative Commentary - MacWhinney
Early Gestalts
• Mimetic patterns do not separate verbs
and nouns
• Me-hand-grab-axe-up-swing-down-cutchips-sound
• This can be imitated as a Gestalt, but
Gestalt storage is expensive
• I chop wood.
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Collaborative Commentary - MacWhinney
Satisfied Preconditions
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Hands were free
Hands were controlled by complex plans
Spatial maps had evolved for self and group
The visual system could generate and store
images
• Visual images encoded hierarchically and open
to recursion
• Vocalization and eye-gaze controlled attention in
face-to-face interaction
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Collaborative Commentary - MacWhinney
Neuronal Support
• Tripling in brain size (some allometric)
• Earlier growth was in specific areas
 Parietal
 Cortical control of vocal channel
• New pressures
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Need for full simulation of the body for mimesis
Storage of mimetic sequences
Processing of mimetic operators
Teaching of mimetic sequences by mothers
Perspective-switching
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Collaborative Commentary - MacWhinney
How successful?
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Expansion to all of Eurasia
At the expense of other hominids
Big, unorganized brain
No vocal systematization
Climate changes of the Pleistocene led to
new pressures
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Collaborative Commentary - MacWhinney
4. Phonology
• Phonological patterning
 MacNeilage and vocal gesture
 Gupta and MacWhinney and the phonological loop
• Making efficient use of lexical storage
• Capitalizes on evolution in TOM and perspective
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Collaborative Commentary - MacWhinney
Vocal Adaptations
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Lower larynx and hence larger (and distinct) pharynx
Longer local cords (at least in adult males)
Aerodynamical streamlined conus elasticus (underside
of vocal cords
Expanded neuronal control of intercostals at 300,000
These adaptations produce loud, efficient, and low-pitched
vocalizations (but not necessarily speech itself).
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Collaborative Commentary - MacWhinney
Facial Musculature
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Collaborative Commentary - MacWhinney
Ears, Teeth
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Collaborative Commentary - MacWhinney
Vocal Cords
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Collaborative Commentary - MacWhinney
Source-Filter Theory
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Collaborative Commentary - MacWhinney
Bent Vocal Tract
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Collaborative Commentary - MacWhinney
Possible Vowels
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Collaborative Commentary - MacWhinney
Neanderthal and Cro-Magnon
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Collaborative Commentary - MacWhinney
Neuronal Support
• Broca’s for lip-smacking becomes Broca’s
for CV syllabic framework
• Phonological loop involving superior
temporal stores lexical items
• Lexical items have access to all of the
brain, but not dynamically
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Collaborative Commentary - MacWhinney
Reuse of earlier mechanisms
• Phonological store allows vocal rehearsal
• Hippocampus stores the episodic basis of
lexical meanings
• DLPFC stores plans for tools use and
mimesis
• Integrated frontal function constructs
group relations: kinship, reciprocals,
hierarchy
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Collaborative Commentary - MacWhinney
5. Phoenix
• Narrowing of evolutionary window at
70,000
• Computed through females, but males
must be similar
• Perhaps due to Toba Batak, perhaps to a
pandemic
• Survivors were an interesting subset of the
earlier population
• Phoenix from the Ashes
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Collaborative Commentary - MacWhinney
Creativity Explosion
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Artifacts at 50,000 - carved bone, amulets
Cave paintings at 30,000
Burial at 30,000
Opposition to Neanderthal
Mithen theory of demodularization
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Collaborative Commentary - MacWhinney
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Collaborative Commentary - MacWhinney
Suspects
• Perspective
• Recursion
• Priesthood
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Collaborative Commentary - MacWhinney
Perspective Hypothesis
unified embodied image
language as a functional neural circuit
perspective
direct
experience
perspective
space/time
deixis
perspective
perspective
plans
social
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Collaborative Commentary - MacWhinney
Evolution and Perspective
• The five periods do not match the four
cognitive levels
• But each level was constructed as a part
of this process
• Each was progressively refined over time
• The phonetic revolution underlies the
grammar, but the grammar maps to
cognition, not phonology
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Collaborative Commentary - MacWhinney
But…
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TOM is developed in chimps
Perspective was important during mimesis
Imitation was present
Imagery was present
Mirror neurons are in monkeys
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Collaborative Commentary - MacWhinney
Recursion
• Next talk: What Chomsky means by
recursion reduces to item-based patterns
• Item-based patterns require
 Items
 Slots
 Features
 Clustering
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Collaborative Commentary - MacWhinney
Patterns from Combinations
• cookie =
“would you please open the cupboard door and
bring me down a cookie”
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want ##### cookie
want # cookie
want cookie
Nim Chimpsky, Washoe, Sara, Lana
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Collaborative Commentary - MacWhinney
Item-based Patterns
• my + X
 Position
 Meaning relation
 Possible fillers
 My little dolly
• Where + X
 Where the wheel goes?
 Where goes the wheel?
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Collaborative Commentary - MacWhinney
Sockets are action-based
--- breaks
Throw__
__give__ __
__kick __
__ running
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Collaborative Commentary - MacWhinney
Feature-based patterns
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big + X, nice + X ….
Adj + X
Adj + N
But what about?
 Actor + Action
 Subject + Verb
 Topic + Comment
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Collaborative Commentary - MacWhinney
Patterns to Creativity
• Item-based patterns provided full recursion
• Recursion linked dynamically to
perspectival systems
• Articulate language users became priests
• Priests constructed the afterworld and
myth
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Collaborative Commentary - MacWhinney
Syntax and Perspective
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Tim saw the Grand Canyon flying to New York.
Jessie stole a picture of *her/herself.
Jessie stole me a picture of her/*herself.
The adults in the picture are facing away from
us, with the children hidden behind them.
• Did the bicyclist appear to fall?
• Tim couldn’t find Mary’s beloved cat.
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Collaborative Commentary - MacWhinney
Social Perspectives
I claim that reason is a self-developing
capacity. Kant disagrees with me on this
point. He says it’s innate, but I answer
that that’s begging the question, to which
he counters, in Critique of Pure Reason,
that only innate ideas have power. But I
say to that, what about neuronal group
selection? And he gives no answer.
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Collaborative Commentary - MacWhinney
Conclusions
• Language evolution was gradual, relying on
coevolution of language, thought and gesture.
• We can distinguish five major periods.
• Recursion was important in recent changes, but
relied on earlier spatial patterns
• Most recent changes involves coordination of
recursion and lexicon with perspective
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Collaborative Commentary - MacWhinney