Language & the Mind Animal Communication LING240 • Are we special among species? Summer Session II 2005 • What are other species capable of? • Are language-learning abilities Lecture 2 related to general cognitive Animal Communication & capacities? Human Instincts • Could language have evolved gradually? Naturally-Occurring Systems Vervet Monkey Alarm Calls • 3 classes of predators • Monkey alarm calls • 3 distinct alarm calls • Packmates respond appropriately even if predator • Bee Dance is not visible • Loud bark (leopard alarm) = run for tree • Birdsong • “cough” (eagle alarm) = rush into the bushes • “chutter” (snake alarm) = stand up & scan ground Dance of the Honeybees What a vervet cannot express ‘deciphered’ by Karl von Frisch, 1919 & onward Under 50 m away Over 50 m away: encodes distance • “I saw a snake near that tree just the & direction - is other day, so watch your feet.” encoding of 2D • Conveys location of space (a bee’s source of “mental map”) • “Where did you say that leopard was?” nectar - every message is unique • “Can you say that again? - I didn’t hear you.” 1 Honeybee What a honeybee cannot express Conversations • “There’s going to be some great • Honeybees can express more than nectar at this really nice spot I know vervets - but the conceptual content soon since the flowers are all in is always “the location of what we bloom.” are all looking for right now” • “I saw a really swank hive a little ways from here - we should totally take over and get ourselves some better digs.” Sparrow Song Variation in Sparrow Song Bird 1 Bird 2 song call • Song is highly structured - notes, syllables, phrases • Regional variation • Sensitive period • Fixed meaning Dialects of the White-Crowned Sparrow (Marler, 1970) 2 Nature & Nurture Features of Human Language • So birdsong seems to have both an • Creativity innate component and a learned • Arbitrariness component • Systematicity (e.g. word order, structure) • We still classify it as an instinct • Displaced reference • Pretense Some Thoughts Teaching Human-like Language • Animal communication systems are quite • Can other species master properties varied of human language such as… • Many features of human language found in other species – sounds • Features of human language never combined – arbitrary words/signs to refer to object in other species – systematic combinations of signs • Extent of human linguistic creativity far – creative use of sign combinations surpasses any other species • Are humans unique in the ability to do • But… interesting lessons for human language this? from studying related systems, e.g. birdsong Alex Alex • Grey parrot, born 1976 • Grey parrot, born 1976 • Trained by Dr Irene Pepperberg (U. • Trained by Dr Irene Pepperberg (U. Arizona) since 1977 Arizona) since 1977 • Impressive ability to speak/understand • Impressive ability to speak/understand …for a parrot …for a parrot 3 Alex’s Language Washoe & Nim Chimpsky • Speech sounds remarkably accurate • Apes taught modified sign language …produced very differently from humans in 1960s & 1970s • Knows names of 100+ objects plus some fixed expressions • Answers simple questions about objects (e.g. about size, color, material) • Requires immense amounts of training Washoe & Nim Chimpsky Kanzi • Benobo (‘pygmy chimp’) • Learned many signs • Born 1980 • Yerkes Regional Primate Center, Atlanta • Able to combine signs Trained by Sue Savage-Rumbaugh & • Sign combinations lacked systematic others use of word order etc. • Grew up with an adult benobo, who was being trained to communicate with • Impressive, but far behind 2-year olds ‘pictograms’, with little success • Kanzi quickly surpassed his guardian Kanzi Creativity in Human Language • Animal languages have a fixed, limited range of messages (vervet • Pictograms remove articulation calls, bee dance, bird song) difficulty • Human language is infinitely creative • Impressive creativity and • Increased expressive power of human systematicity - best shown to-date language is not just a difference of degree - human language is • Still falls short of 2-year olds fundamentally different 4 Creativity in Human Language Language vs. Communication • Creativity of human language results • Communication: conveying information between a from its combinatorial properties messenge-sender and a message-receiver • Small number of memorized “pieces” • Language: one type of communication system yield vast range of possible messages used by human beings, and the only one we are aware of in any species that takes a finite number • Human “pieces” are sounds, words, of “pieces” and combines them with a finite set of and phrases combinatorial rules to yield an infinite number of messages about any topic. So what is it that humans learn? So what is it that humans learn? Option 1: Option 2: • Other species can master the • Very little - similar to teaching bees the rudiments of human language bee dance! • Human language is not a major • Other species are not ‘designed’ for departure from other species human language • Evolutionary precursors to human • Learn how human instincts work by language studying humans! Some More Thoughts Someone Else’s Thoughts • Examination of other species clarifies how The fact that a dog can be trained to walk on its hind unusual human language is legs does not prejudice the claim that bipedal gait is • Other species have interesting genetically coded in humans. The fact that we can communicative tricks - different from ours learn to whistle like a lark does not prejudice the species-specificity of birdsong. • Some species can learn some impressive ‘language tricks’ … doesn’t teach us much (Fodor, Bever & Garrett, 1974 about how human language works The Psychology of Language) 5 So let’s talk about this Why do humans have language? “instinct” thing… • Bats use sonar to echolocate; homing • Because we’re smarter than other animals? pigeons know where home is; deer rub • Because we have a bigger brain? antlers against trees; spiders spin webs; • Because our mouths have a special shape? dolphins play; some primates walk • Because somebody took the time to teach • Special properties of individual species, not us? related to “general intelligence”, develop automatically • Another “instinct”: human language • …or because that’s just something that humans do? Why call language an instinct? Why call language an instinct? • Species specificity • Species specificity • Uniformity throughout human species • Uniformity throughout human species • Humans spontaneously create languages • Humans spontaneously create languages • Independence from other mental abilities • Independence from other mental abilities • Sensitive period for learning language • Sensitive period for learning language Species Specificity The point “We may not be able to take flight by flapping our upper extremities, but we are the only species known that can • Other species simply can’t learn rationally discuss our inability to do so.” human language -Stephen Anderson, Doctor Dolittle’s • The communication systems of other Delusion animals are not even remotely as complex as human language. 6 Why call language an instinct? Uniformity • Species specificity • All humans master a human language … • Uniformity throughout human species except in extreme circumstances • Humans spontaneously create languages • Independence from other mental abilities • Sensitive period for learning language • All human languages are remarkably similar in their basic properties. Uniformity Why call language an instinct? • All human languages are able to express an infinite number of never-before-expressed • Species specificity sentences • Uniformity throughout human species • Humans spontaneously create languages • All are able to express ideas of a similar level of complexity • Independence from other mental abilities • Sensitive period for learning language • Even the form of languages seems to vary in restricted ways Humans Spontaneously Create Something heard & learned… Language: Everyday cases • Poverty of the Stimulus: Every child • Who did Jareth see Sarah with in his has to go beyond the data heard in crystal? the environment. • Children acquire many linguistic generalizations that experience could not have made available 7 Something unheard but still Every child has to go beyond learned… the environment • *Who did Jareth see Sarah and in his • Children cannot hear every possible sentence crystal? of their native language • Children never hear impossible sentences • Both of these sets are infinitely large, yet we all end up generally agreeing about which ones are possible and which ones are impossible Children spontaneously create Children create their own system language: Extreme cases “It breaked.” • Input is totally absent - home sign systems of deaf children “Don’t giggle me!” • Input is inconsistent - Simon “Does she doesn’t like that?” • Input is not a full language - pidgins and “What she does eat?” creoles Children spontaneously create Simon (Singleton & Newport) Input: language: Extreme Cases - Parents were late learners of ASL - Parents used required ASL verb inflections 60% of • Input is totally absent - home sign the time (either omitted them or used the wrong ones) systems of deaf children - In school, only exposed to a signed English system Output: • Input is inconsistent - Simon - As good as “native of native” children on most aspects of ASL inflection - Simon’s own use of verbs of motion surpasses the • Input is not a full language - pidgins and performance of his parents creoles -