Unity and diversity in human language W. Tecumseh Fitch Philosophical Transactions of the Royal Society, B 2011, 366, Language is unique to humans, chimps do not have language Suggests that some genetic aspects of language were selected shortly after the split with LCA (about 6mybp), but other aspects of language were probably not in place until much more recently (50,000 ybp)

Two starting assumptions 1. “humans are born with an instinctual desire to learn language, and the neural equipment to do so. “ 2. “the human capacity to acquire language is composed of multiple separable but interacting mechanisms, no one of which alone is adequate for language acquisition” Some mechanisms are shared with other species (FLB; using gesture/vocalization to manipulate others’ behavior); Some are unique to humans (FLN; recursion, hierarchically- nested syntax). This is the priest all shaven and shorn, That married the man all tattered and torn, That kissed the maiden all forlorn, That milked the cow with the crumpled horn, That tossed the dog, That worried the cat, That killed the rat, That ate the malt That lay in the house that Jack built.

What is language? “I use ‘language’ to denote any system that freely allows concepts to be mapped to signals, where the mapping is bi-directional (going from concepts to signals and vice versa) and exhaustive (any concept, even one never before considered, can be so mapped). Although all animals communicate, and all vertebrates (at least) have concepts, most animal communication systems allow only a small subset of an individual’s concepts to be expressed as signals (e.g. threats, mating, food or alarm calls, etc.) “

Is language innate? Term “innate” is confusing and often mistakenly thought to mean “genetically determined.” “a vast store of information in any human language must be learned (least controversially, every word of every language is learned), and thus contemporary debates concern not this fact, but whether a human child is born with a set of mechanisms or constraints that help this learning along. No linguist believes that ‘language is innate’ in any simple superficial sense.” “The term ‘innate’ can defensibly be used as a shorthand for ‘reliably developing’ or ‘canalized.’

Universals in Language Original notion of universal grammar: obvious linguistic universals (e.g. all languages have words; utterances express meaning, etc). Later notion: Linguistic universal meant “statistical regularities” of language. If a language has x, then it will very likely have y” If a language marks case with inflections then word order is less relevant and vice-versa. UG: Chomskian notion – biological endowment that allows children to efficiently acquire language. FLN; the “instinct” to learn language. “In summary, the search for linguistic universals has proceeded from the eighteenth-century assumption of a rather superficial list of features common to languages (every language has words, every language has nouns and verbs) to a far more abstract set of generalizations and regularities about the human language faculty, and the biological endowment that a human child uses to acquire language.”

Diversity in language “I know of no animal communication system that comes close to matching the range of diversity in the more than 6000 existing human languages” Modality: gestural vs. spoken Phonemes: 11 to 150 Vowels: 3 to over 15 Presence or absence of bound morphemes (-s –ed)

Bauplan analogy for language A basic structural plan (universals) which can be efficiently and significantly modified by adjusting just a few control mechanisms.

False analogy: general cognitive vs. language specific mechanisms Is an evolved mechanism or structure specifically for language or is a general purpose cognitive mechanism that simply participates in language production? If general – then shared with other species If l-s – then unique to humans Problem: often the distinction simply cannot be made Ex: vocal imitation is uniquely human among primates and essential for cultural transmission of linguistic sounds (l-s mechanism); but VI is present in birds and essential for learning of song. In humans was this a mechanism for imitating song-like vocalizations originally and not for language? We may never know. Similar situation for Foxp2 gene and Broca’s area

Conclusion Argues that Bauplan approach probably provides best framework for guiding language research. Diversity with general unifying constraints “particular languages correspond to specific solutions to the constraints imposed by human biology on language acquisition and historical change.”