Introduction
to
Linguistics
III
The evolution of language
Historical views of language acquisition
Introduction
to
Linguistics
B.F. Skinner
J. Piaget
N. Chomsky
Behaviorist theory
Constructivist theory
Nativist theory
infants learn language from
other human role models
through a process involving
imitation, rewards, and practice
Language is acquired within the
context of the child's broader
intellectual development.
Language is not an independent
system, but part of our general
cognitive makeup
Children are born equipped
with an innate template for
language, and this blueprint
aids the child in the task of
constructing a grammar for
their language
Poverty of stimulus problem
The poverty of the stimulus argument is the claim that primary linguistic data
(i.e. the linguistic utterances heard by a child) do not contain enough
information to uniquely specify the grammar used to produce them.
• Premises:
- Language is not explicitly taught
- The degenerate nature of data
- The rarity of negative evidence
‫הנה ילדים שאהבו את הסרט‬
‫*הנה ילדים האהבו את הסרט‬
Positive evidence
Negative evidence
the set of grammatical sentences
that the language learner has
access to, as a result of
observing the speech of others
the evidence available
to the language
learner about what is
not grammatical
Introduction
to
Linguistics
Poverty of stimulus problem
• Language acquisition is like learning chess:
- Only by watching
- No explanation of the rules
(knowledge about language is never taught)
- Some portion of the moves are illegal
)children often hear ungrammatical fragments of speech)
- But we don’t know which!
(Negative evidence is rare)
Conclusion: children must have some form of innate Language
Acquisition Device (LAD) that provides additional knowledge to
language learners
Introduction
to
Linguistics
Language acquisition device
Introduction
to
Linguistics
More evidence for an innate human capacity to acquire language comes from the following observations:
• The stages of language development occur at about the same ages in most children
• Children’s language development follows a similar pattern across cultures.
• Deaf children who have not been exposed to a language may make up their own language
(Nicaraguan Sign Language case)
The Hardest problem in science?
Introduction
to
Linguistics
• In 1859, Darwin’s published his monumental work,
“on the origin of species”, which is considered to
be the foundation of evolutionary biology
• How can we track down the evolution of language?
It is nearly impossible to bring direct evidence
of the form of primitive language…
There are no language fossils
• In 1866, the Linguistic society of Paris chose to put a ban on discussion of the of
the evolution of language – treating it as so speculative as to be worthless…
• “The attitude of most linguists to evolutionary theories of the origin of language tends to be one of
agnosticism. Psychologists, biologists, ethologists and others might say, if they so wish, that language
must have evolved from some non-linguistic signaling-system; the fact remains, linguists might reply,
that there is no actual evidence from language to support this belief”
(Lyons, 1977)
Introduction
to
Major transitions
Linguistics
Eight major transitions in the evolution of life:
• These events in the history of our planet have brought
radical changes in the way evolution works
• Why is the emergence of language such a significant
event?
• These transitions have some features in common…
Maynard Smith & Szathmáry’s (1997)
One way of thinking about language is as a coding system that maps between two spaces:
the space of concepts and intentions on the one hand, and of articulation and perception
on the other
Introduction
to
Language r/evolution
Linguistics
Worldwide Spread of Homo Sapiens
Neanderthal
australopithecine Homo erectus
Language r/evolution
Introduction
to
Linguistics
What was so revolutionary in the Homo Sapiens’ language?
• The Lion-by-the-river theory
• The social brain hypothesis
• Fictive language theory
Introduction
to
Language r/evolution
Linguistics
What was so revolutionary in the Homo Sapiens’ language?
Unbounded (DNA-free) transmission of cultural information
Biological explanations
History story-telling
The Emergence
of language
Introduction
The emergence of language
to
Linguistics
“Language is a product of our large brain size”
Definitely not!! Large brain does not predict language capacity
• Evidence from high-functioning human microcephalics
Normal head
size
microcephaly
• Autistics have significant problems in both the acquisition and expression
of language, and yet early in development often have larger brains than
healthy children
• Children with one hemisphere removed prior to the full acquisition of
language often display normal language expression and comprehension
Social evolution of language
• British anthropologist Robin Dunbar’s “gossip” theory is based
on social complexity
• Dunbar pointed out that the majority of people’s conversations are devoted to gathering news
either about the people they are speaking to or about third parties: in other words, to gossiping.
• Among primates, neocortex size varies in proportion to social group
size. Apparently, the larger the group a primate lives in, the more
brain it needs to keep track of social relationships within the group.
• Social pressure leads to selective pressure: Dunbar
suggests that larger brains evolved in primates in
order to permit larger social groups
• Dunbar Number: If we look at human brain size from the
perspective of this hypothesis, we predict a "natural"
group size for humans of about 150.
Introduction
to
Linguistics
Social evolution of language
• In primate societies, it is grooming (picking nits out of fur) that plays a major factor in
establishing and maintaining social bonds.
Introduction
to
Linguistics
• The bigger the primate group, the more time on average each member spends in grooming others.
• If we look at human social relations in this perspective, then with a group size of 150, we
should have to spend 40% of the day in grooming. This is far too high to be practical -- the
highest actual proportion observed among primates is 20% (Gelada baboons).
• Dunbar suggests that our ancestors, facing hard times on the
African plains, very badly needed to live in larger groups.
"Gossiping" (in whatever form it first arose) made it possible
to form and maintain social bonds more efficiently than
grooming, both because more than two can do it at once, and
also because you can actually do some useful work (like
gathering or processing food) at the same time.
The emergence of language
Broca’s and Wernicke’s homologues have
been identified in non-human primate brains
Introduction
to
Linguistics
Lesioning the monkey homologue of Broca’s area
does not impair vocalization
Monkey calls instead depend upon the limbic
system and brainstem (more ancient systems)
comprehension of species-specific vocalizations
seems to depend on similar neural substrates in
humans and macaque monkeys
Like Broca’s area, human Wernicke’s area has
functional properties not found in its non-human
homologue, such as phonological processing
Rilling, 2014
The emergence of language II
“Language is a product of macro-mutation”
Introduction
to
Linguistics
Probably not.
It is hard to imagine that a single mutation could have resulted in such a complex behavior
A gradual story for the evolution of the eye is possible:
it turns out that there are “intermediate” eyes that are
indeed useful and there is a plausible evolutionary
trajectory from these intermediate forms to the
modern eye.
Is a gradual evolution of human
language plausible?
Evolutionary questions
Introduction
to
Linguistics
Language origin – the first step from something that is not language
to something that is language
Language evolution – the gradual development of speech-to-meaning mapping
There is a huge gulf between the communication systems of our nearest
primate relatives and human language. If language is a one-off
phenomenon - an autapomorphy - then how can we apply the standard
methodologies from evolutionary biology?
“We’ll start by speaking in simple declarative sentences.”
Dividing the language faculty
• the problems in discussions of language in its evolutionary context
may arise from treating the language faculty as a unitary whole
Introduction
to
Linguistics
Minimal account of human uniqueness
• As an alternative, Hauser, Chomsky & Fitch propose two different
senses of the term biological language faculty:
- FLB (the faculty of language in the broad sense)
- FLN (the faculty of language In the narrow sense)
• More specifically, they put forward the strong hypothesis that FLN
is essentially limited to a mechanism implementing recursion
• Having made this distinction, they set out three logically
possible hypotheses about the evolution of the faculty of
language:
1. FLB is homologous to animal communication. All aspects of FLB
(including FLN) can be found relatively unchanged in animals
2. FLB is a derived, uniquely human adaptation to language.
3. Only FLN is uniquely human.
Hauser, Chomsky & Fitch, science 2002
Debating the language faculty
Introduction
Linguistics
• Pinker & Jackendoff (2005) do not accept this minimal
description, and argue that there is much more that is special to
language and to humans than merely the capacity for recursion.
• Firstly, they suggest that there are non-syntactic aspects of language that are
uniquely human. For example, for them the huge size and rapid acquisition of
the lexicon strongly suggests that this is a uniquely human adaptation.
• A second criticism that Pinker & Jackendoff (2005) have is that
treating FLN as containing simply a mechanism for recursive
computation oversimplifies the syntactic aspects of human language.
to
Introduction
to
The descended larynx
Other mammals / Human infants
Linguistics
Humans (Adult)
Language gene?
• KE family: In 1990, scientists became interested in a
certain family in London, half of whose family members
have speech disorders.
• By analyzing the KE family DNA sequences, scientists
found that the speech problem was caused by a
mutation in the FOXP2 gene located on chromosome 7
region 7q31
Introduction
to
Linguistics