How Languages evolved. Rikhiya Ghosh Graduate Student, RAIR Computer Science

Transcription

1 How Languages evolved Rikhiya Ghosh Graduate Student, RAIR Computer Science

2 What is Communication?

3 What is Communication?

4 Primate Communication

5 Vocalization in Primates Same vocal repertoire within a species Connection between vocal call and its eliciting situation fixed No change or little change in vocalizations with human contact, isolation or raising by other nonhuman primate species Flexibility only in presence or absence of company Indiscriminate broadcasting

6 Gestures in Primates Varied number of gestures Non-standardisation of gestures Attention of recipient Sequence of gestures Learn novel gestures

7 Types of primate gestures R recipient). See Call and Tomasello Intention-Movements Gestural Action Arm-raise C raises arm toward R, beginning hitting. Touch-back Hand-beg Head bob Arm-on C touches back of R lightly, beginning climbing on. C places hand under R s mouth, beginning taking food. C bobs and weaves in bowing position at R, beginning play. C approaches R and places arm on R s back, beginning dragging. Goal/Function Initiate play Request ride-on-back Request food Initiate play Initiate tandem walk Attention-Getters Ground-slap C slaps the ground (or an object) and looks to R. Often play Poke-at C pokes a body part of R. Various Throw-stuff C throws something at R. Often play Hand-clap Back-offer C slaps own wrist or hand, as approaches R. C insistently puts its own back in the face of R. Often play Typically grooming Source: Call and Tomasello, 2007

8 Pointing

9 Human gestures Deictic Gestures Iconic gestures Pantomime Pointing

10 Pointing in Infants Skill Level Understanding Intentions Shared Intentionality Point to Request Help - Imperative Point to Share Attitudes - Expressive Point to Offer Help - Informative Demand Action Share Emotions Offer Help Age in Months

11 Co-operation Model Shared intentionality Communicative context and reference Social motivations: Joint goal Other communicative motives : Request, Inform, Share Mutual Helpfulness and Co-operative Reasoning : Gricean Theory and recursive mindreading Cultural group selection Eye movement

12 Language and Thought Sapir-Whorf Hypothesis : Counting, Languages of Australian Aborigines Cognitive Therapy (Beck) : Emotions and behaviors are caused by internal dialogue Behavioral Economics : More vividly described events are more likely to be true Other theories

13 Superiority of Vocal Modality Not natural, more convention-based, drift to arbitrary Holophrasis : Single word for a complex idea Advantageous with all other organs free to do something else Ape attention-getters - - -> Human pointing > Demonstratives, Deictics in language Ape intention movements - - -> Human iconic gestures > Content words(noun, verbs)

14 Origin of Language

15 Approaches Continuity Theories : Pinker, Ulbaek Discontinuity Theories : Chomsky, Berwick, Pääbo Genetically encoded faculty : Presence or absence of language-relevant FOXP2 gene Socially learned tool of communication : Tomasello

16 Speculations of Max Müller Bow-wow or cuckoo theory : imitations of other animals Pooh-pooh : emotional interjections and exclamations Ding-dong : vibrating natural resonance Yo-he-ho : synchronize muscular labor Addition by Paget : Ta-ta (tongue movements mimicking manual gestures)

17 Signalling Theory Costly Signaling Honest Signaling Dishonest Signaling

18 Mother Tongues Hypothesis (Fitch, 2004) Communication between mother and biological offspring Mutual trust due to shared gene Extend to far relatives

19 Obligatory reciprocal Altruism (Ib Ulbæk)

20 Gossip and grooming Hypothesis (Dunbar)

21 Gestural Theory Evidence Similar neural systems for gestures and vocalization Nonhuman primates can gesture Why the shift to vocalization? Hands-free approach Visibility issues Composite multimedia approach

22 Mirror neurons What? Homologous area in monkeys Provide action-learning, imitation learning, simulation of others behavior Evidence Cytoarchitectonic homology between monkey premotor area F5 and Human Broca s area fmri results of gesturing Granger causality data analysis

23 FOXP2 gene Grammar gene (Pinker, 1994) Vocal articulation (Corbalis, 2004) Associated with non-word repetition, real word reading efficiency, rapid oral reading (Peter et al, 2011) Mutation of the gene causes congenital dyslexia Little different from FOXP2 gene in Homo Neanderthals Present in almost all nonhuman primates

24 Grammar

25 Foundations of Grammar APES Grammar of Requesting Homo Grammar of Informing Earlier Sapiens Grammar of Sharing Later Sapiens Simple Syntax Parse experience into events and participants Combine gestures toward single goal Serious Syntax Syntactically mark roles in events ID participants in joint attentional frame Fancy Syntax Relate events in narrative Track participants across events Entrenched Normatively Grammatical Gesture Sequences Combos of Pointing Intention-Movements & Sign and Vocal Language Mixed Mainly Vocal Language Source : Tomasello, Origins of Human communication

26 Conventionalization of Linguistic Constructions Culturalhistorical evolution Language Change : Change in constructions

27 Linguistic construction Gestalt properties of conventional grammatical constructions "The whole is other than the sum of the parts - Kurt Koffka Construction give meanings, override meanings of words The dax got mazzed by a gibber

28 Language creation and change Open and dynamic : Need to be efficient Resultative Construction : He pulled the door open and it opened -> He pulled the door open Relative construction : Mary gave us food. She was wearing green sweater. -> Mary, who was wearing green sweater, gave us food. Sentential complement construction : You will pass the test. I know that. -> I know that you will pass the test. Infinitival construction : I want this. I buy it. -> I want to buy it.

29 Language Creation and Change Reduce number of words, number of syllables. going to -> gonna, on top of -> atop Combining constructions Functional reanalysis

30 Chomskian Universal Grammar Human brain contains limited set of constraints for organizing language. Creole languages Criticisms and Piranha language

31 Chomsky hierarchy of Languages