Language Evolution IV: HCF + PJ + FHC + JP =/= ♥

As could be expected, the framework established by HCF led to much criticism from proponents of what HCF called hypothesis 2. Thus, in 2005, Pinker and Jackendoff (PJ) responded to HCF by asking:

“The faculty of language: what’s special about it?”

The controversy led to further discussion in the same year when Fitch, Hauser and Chomsky (FHC) defended their viewpoint in

“The evolution of the language faculty: Clarifications and implications”

and Jackendoff and Pinker renewed their disagreement debating

“The nature of the language faculty and its implications for the evolution of language“.

PJ’s first critique mainly focuses on the “recursion-only claim” of HCF, because they feel that there is more that is special to language. Furthermore, they question that recursion evolved as an exaptation (Pinker/Jackendoff 2005: 205). They especially defend the “Speech is Special” (SiS) hypothesis posed by Alvin Liberman and others, which was rejected by HFC (Pinker/Jackendoff 2005: 206), because it seems that the speech perception system and vocal production in humans have been specially adapted for language (Pinker/Jackendoff 2005: 206-209), and not for vocal imitation or size exaggeration as HCF suggested (Pinker/Jackendoff 2005: 209f.). They also assess that

"words, as shared, organized linkages of phonological, conceptual, and grammatical structures, are a distinctive language-specific part of human knowledge” (Pinker/Jackendoff 2005: 215).

They also question the usefulness of the FLB/FLN distinction in general and criticize HCF/FHC’s blurring of the difference between homology and analogy. (Jackendoff/Pinker 2005: 214-216) Further, they cite genetic evidence as an argument against the recursion-only claim, namely that the FOXP2-gene, though present for example in mice, chimpanzees, and humans has been positively selected in the human lineage, and is critical for

"articulation, production, comprehension, and judgments in a variety of domains of grammar, together with difficulties in producing sequences of orofacial movements”

and not only for recursion (Pinker/Jackendoff 2005: 218).
Finally, they criticize Chomsky’s Minimalist Program (MP) as a rationale of HCF’s research program, which they find problematic because of the massive counterevidence against it. In their opinion, the adaptationist view of language seems much more plausible (Pinker/Jackendoff 2005: 231).

In their reply, FHC emphasize their independence of the MP (Fitch/Hauser/Chomsky 2005: 183), and stress that

"most of the data PJ discuss concern mechanisms that are part of FLB by definition, because related mechanisms exist in other species and/or other cognitive domains”

(Fitch/Hauser/Chomsky 2005: 204), which in their view clearly is an adaptation shaped by natural selection (Fitch/Hauser/Chomsky 2005: 189). They further argue that, though welcoming demonstrations

"that other mechanisms should be added to FLN” (Fitch/Hauser/Chomsky 2005: 204),

SiS would not present a testable, strong hypothesis and thus could be accepted as given (Fitch/Hauser/Chomsky 2005: 219).
Citing the phoneme discrimination abilities by macaques and other evidence as arguments against SiS (Fitch/Hauser/ Chomsky 2005: 195), they conclude that their

“hypothesis 3 is not only plausible, but that no data refuting it currently exist” (Fitch/Hauser/Chomsky 2005: 205).

FHC also introduce the current utility/functional origins dichotomy, on which I elaborated in chapter 3, and argue that

“from an empirical perspective, there are not and probably never will be data capable of discriminating among the many plausible speculations that have been offered about the original function(s) of language.”

Thus, Pinker and Jackendoff’s framing of questions about language evolution would be of little scientific value (Fitch/Hauser/Chomsky 2005: 185f.) JP contradict this statement. In their view, current adaptation, „what the trait was selected for in the species being considered”, poses one of the biologically most interesting questions about a trait and can be addressed empirically by reverse-engineering or functional analysis, which is able to “shed light on its likely evolutionary history.” (Jackendoff/Pinker 2005: 212-214).

The debate regarding recursion heated up once again when Gentner et al. (2006) claimed to have found recursion-abilities in starlings, and Perruchet & Rey criticized Fitch and Hauser’s original experiment that established the inability of monekys to master “phrase structure grammars” (Fitch & Hauser 2004). Regarding the ability of recursion in starlings, these two posts are especially interesting. First this one by Mark Liberman, and the other, where David Beaver regards the recursion-abilities of starlings which in the respect of center-embedded grammars actually seem to be better than ours, and comes to the ironical conclusion that

“we have firm and amazing evidence for a biologically unique language module. The trouble is, starlings have it, and we don't.”

Other excellent post from the Language Log about HCF's claims can be found here, here, here, here, and here.

References:


Hauser, Marc D., Noam Chomsky and W. Tecumseh Fitch 2002. “The Faculty of Language: What Is It, Who Has It, and How Did It Evolve?” In: Science 298, 1569-1579.

Fitch, W. Tecumseh and Marc. D Hauser. 2004. “Computational Constraints on Syntactic Processing in a Nonhuman Primate” In: Science 303: 377-380


Fitch, W. Tecumseh, Marc D. Hauser and Noam Chomsky 2005. “The Evolution of the Language Faculty: Clarifications and Implications.” In: Cognition 97, 179-210.

Jackendoff, Ray & Steven Pinker 2005. “The Nature of the Language Faculty and its Implications for Evolution of Language (Reply to Fitch, Hauser, and Chomsky).” In: Cognition 97, 211-225.

Pinker, Steven & Ray Jackendoff 2005. “The Faculty of Language: What’s Special about it?” In: Cognition 95, 201-236.

Language Evolution III: Hauser, Chomsky, Fitch 2002

When Hauser, known for his strong continuist position, and Chomsky, known as a strong discontinuist, collaborated on the programmatic paper “The Faculty of Language: What Is It, Who Has It, and How Did It Evolve?” together with W. Tecumseh Fitch, it was, as Derek Bickerton states,

“almost as if Ariel Sharon and Yasser Arafat had coauthored a position paper on the Middle East” (Bickerton 2007: 519).

Just as the 1990 paper by Pinker and Bloom, this paper reviews other hypotheses about language evolution and then, synthesizing a massive amount of comparative data, proposes a new research agenda. It gives a good impression of the state of the discussion in the first decade of the twenty-first century, especially when taking into account the heated debate that revolved around this research program between these authors and Pinker and Jackendoff, which I will describe in my next post.

HCF distinguish between the faculty of language in the broad sense (FLB) and the faculty of language in the narrow sense (FLN). FLB consists of a “sensory-motor” system, including phonetics and phonology, as well as a “conceptual-intentional” system, including semantics and pragmatics (Fitch/Hauser/Chomsky 2005: 182), and maybe other systems (Hauser/Chomsky/Fitch 2002: 1571f.). It

“includes all of the many mechanisms involved in speech and language, regardless of their overlap with other cognitive domains or with other species”.

FLB also comprises FLN, a subset which contains the aspects of language that are responsible for the fact that humans are the only species capable of language, and thereby should be a unique aspect of language as well as humanness (Fitch/Hauser/Chomsky 2005: 180f.).
Thus, research into the evolution of language is divided into three different areas of inquiry, according to the computational systems that comprise the faculty of language, as well as a fourth that is concerned with the interfaces between them. For each component, it has to be assessed whether the capacity is a uniquely human trait or if it is shared with other species, second, whether it developed gradual or saltational, and third, if it was an adaptation for communication or an exaptation of some other computational function (Hauser/Chomsky/ Fitch 2002: 1571).

HCF present three hypotheses which display the opinions of various scholars, with the third as their own viewpoint. The first hypothesis assumes that the faculty of language is strictly homologous to communication components of animals. The second hypothesis, which for example is stated by Pinker and Bloom, is that the faculty of language is a derived, uniquely human and highly complex adaptation for language “and many of its core components can be viewed as individual traits that have been subjected to selection and perfected in recent human evolutionary history”, and can be accounted for by natural selection (Hauser/Chomsky/Fitch 2002: 1572). HFC take a different stand. Their hypothesis is that only the core component of recursion, that is narrow syntax and the mappings to interfaces of FLB,

“is recently evolved and unique to our species” (Hauser/Chomsky/Fitch 2002: 1573).

Furthermore, they argue that “FLN may have evolved for reasons other than language” (Hauser/Chomsky/Fitch 2002: 1571), and that recursion could be an exaptation that originally

“evolved to solve other computational problems such as navigation, number quantification, or social relationships” (Hauser/Chomsky/Fitch 2002: 1578).

FHC emphasize that their hypothesis needs further empirical research (Hauser/Chomsky/Fitch 2002: 1578) but is superior to many other theories because it presents itself in a tentative and testable manner (Hauser/Chomsky/Fitch 2002: 1572). They advocate that inquiry into problems of language evolution is in need of massive multidisciplinary efforts and much more sampling of comparative data to assess whether a trait evolved specifically for human language or is homologous to animal computations,

“although it may be part of the language faculty and play an intimate role in language processing” (Hauser/Chomsky/Fitch 2002: 1572).

One thing I have to say about the article is that, although I wrote that it offers a good starting point, it actually is pretty murky and unclear, and without reading their “Carifications and Implications” I probably wouldn’t have understood what the whole paper really was about. And I think that the description of the language faculty as “narrow syntax and the mappings to interfaces of FLB,” doesn’t really tell us much regarding explanatory adequacy or how the thing really is supposed to work.

Nevertheless, or maybe even because of this, their proposal caused quite a fuzz, both in the blogosphere (An excellent discussion by Carl Zimmer can be found here (Part I) and here (Part II)
and in the form of other articles launched to attack or to enforce HCF’s theory. The most prominent attack probably came from Steven Pinker and their paper “The Faculty of Language: What’s special about it?” I will describe the debate between those two ‘teams’ in my next post.

P.S.: Over at the Language Evolution blog, you can find the second presentation in a series about "Major Language Evolution Papers", this time about a paper by Mesoudi et al. (2004), which discusses the cultural dynamics of evolutionary processes.

References:

Bickerton, Derek 2007. “Language Evolution: A Brief Guide for Linguists.” In: Lingua 117, 510–526.

Fitch, W. Tecumseh, Marc D. Hauser and Noam Chomsky 2005. “The Evolution of the Language Faculty: Clarifications and Implications.” In: Cognition 97, 179-210.

Hauser, Marc D., Noam Chomsky and W. Tecumseh Fitch 2002. “The Faculty of Language: What Is It, Who Has It, and How Did It Evolve?” In: Science 298, 1569-1579.