Six Candidates for What Makes Human Cognition Uniquely Human

One of the key candidates for what makes human cognition unique is of course language and symbolic thought. We are “the articulate Mammal” (Aitchison 1998) and an “animal symbolicum” (Cassirer 2006: 31). And if one defining feature truly fits our nature, it is that we are the “symbolic species” (Deacon 1998). But as evolutionary anthropologists Michael Tomasello and his colleagues argue, “saying that only humans have language is like saying that only humans build skyscrapers, when the fact is that only humans (among primates) build freestanding shelters at all” (Tomasello et al. 2005: 690).

Language and Social Cognition

According to them and many other researchers, language and symbolic behaviour, although they certainly are crucial features of human cognition, are derived from human beings’ unique capacities in the social domain. As Willard van Orman Quine pointed out, language is essential a “social art” (Quine 1960: ix). Specifically, it builds on the foundations of infants’ capacities for joint attention, intention-reading, and cultural learning (Tomasello 2003: 58). Linguistic communication, in this view, is essentially a form of joint action rooted in common ground between speaker and hearer (Clark 1996: 3 & 12), in which they make “mutually manifest” relevant changes in their cognitive environment (Sperber & Wilson 1995). This is the precondition for the establishment and (co-)construction of symbolic spaces of meaning and shared perspectives (Graumann 2002, Verhagen 2007: 53f.). These abilities, then, had to evolve prior to language, however great language’s effect on cognition may be in general (Carruthers 2002), and if we look for the origins and defining features of human uniqueness we should probably look in the social domain first.

Corroborating evidence for this view comes from comparisons of brain size among primates. Firstly, there are significant positive correlations between group size and primate neocortex size (Dunbar & Shultz 2007). Secondly, there is also a positive correlation between technological innovation and tool use – which are both facilitated by social learning – on the one hand and brain size on the other (Reader and Laland 2002). Our brain, it seems, is essential a “social brain” that evolved to cope with the affordances of a primate social world that frequently got more complex (Dunbar & Shultz 2007, Lewin 2005: 220f.). Thus, “although innovation, tool use, and technological invention may have played a crucial role in the evolution of ape and human brains, these skills were probably built upon mental computations that had their origins and foundations in social interactions” (Cheney & Seyfarth 2007: 283).

Language, Mental Representations, and Symbolic Thought

But this of course does not mean that we expect all other unique aspects of human cognition to be derivative of social cognition. The development of higher social cognition only presented the enabling context and cognitive starting point for other human mental capacities to evolve. To pick up the example again, language, for instance, does not only have an interactive function but also a symbolic one. It creates ‘symbolic assemblies’ that function as form-meaning pairings (Evans & Green 2006: 6f.). But the ability to acquire arbitrary symbolic units itself does not appear to be uniquely human, as it has been demonstrated in great apes, parrots, dolphins and dogs (see Tomasello 2008: 254ff.). But there are two essential differences between the symbolic abilities of humans and other animals: First, even with lexigram- or sign language-trained apes there appears to be nothing that even comes close to the production and joint engagement skills possessed by human children (production) or even pre-verbal infants (joint engagement) (Tomasello 2008: 109ff.).

Secondly, human symbols and concepts function as ‘decoupled representations’ which are not directly bound to a reaction pattern as in most other animal species, including symbol-trained animals, and enable significant “response breadth” and planning (Sterelny 2003: 29f.). In addition, symbolic thought and linguistic usage does not only rely on the comprehension and production of arbitrary signs, but essentially depends on our capacity for abstract, relational, analogical, higher-order, hierarchical and role-governed compositional thought. (Deacon 1998, Jackendoff 2007, Penn et al. 2008).

We now have two tentative candidates for what makes us special:

(1) The capacity to develop a shared point of view or “we-perspective” (Tuomela 2007: 46f.) and jointly engage in and attend to shared goals, plans and intentions in a cooperative collaborative activity within a joint attentional frame and a shared frame of reference (Tomasello et al. 2005).

(2) A conceptual system that is able to reinterpret and re-describe sensory as well as cognitive data and store them in an abstract, decoupled format that can be used for symbolic, relational and analogical reasoning (Penn et al. 2008).

We can now imagine a step in evolution where these two capacities were further integrated, yielding the analogical realization that others are “like me” (the capacity developed to

(3) actively attribute mental states to others in the same sense as one experience mental events and states oneself, that is to, have a “theory of mind” (Premack & Woodruff 1978).

Further, an integration of these capacities, and continuing collaborations and mutual engagements in social and other activities, would lead to the emergence of

(4) shared, intersubjectively overlapping frames of references or coordinate systems into which abstract and non-abstract conceptual representations could be integrated and imported in a systematic fashion, and within which shared percepts and concepts could be blended, unified, and related to each other in a role-governed fashion. (Bühler 1934, Fauconnier & Turner 2002).

In short, the first species in the hominin line who developed this capacity would not only have shared a perceptual world with his or her conspecifics, but they would inhabit a shared mental world. In this collective “we-perspective” and shared frame of reference mediated by joint engagement, they would then be able to create a shared “symbolic niche” in which meaningful cultural practices and shared symbolic constructs, such as institutions, could be co-created and which would ‘come alive’ and have actual real-world significance (Harder fc, Tuomela 2007). By jointly attending to and attaching meaning to cultural artefacts and practices homo gave them intersubjective value and reality and created ‘institutional realities’ (Searle 1995, Moll & Tomasello 2007). It is probable that from the dawn of human culture cognition accelerated in a spiralling and cumulative cognition-culture feedback loop

Additionally, when we are able to project ourselves and others into the same frame of reference, and can also project more abstract symbolic units into this coordinate system, it follows that along and co-evolving with these other changes a capacity

(5) for projecting ourselves and others backwards or forwards into past and future situations is probable to have evolved, that is, a capacity for mental time travel, including the ability to retrieve and re-live episodic memories of past autobiographical events (Tulving 2005) as well as prospective foresight enabling the planning of future actions and events (Suddendorf & Corballis 2007).

Finally, these changes were certainly accompanied co-evolutionary by a means of externalising shared proto-concepts and communicatively coordinating cooperative activities in a flexible manner via the vocal and gestural level. (Hurford 2007, Tomasello 2008). At some time, concepts became public, that is “they became the sorts of things that lots of people can, and do, share” (Fodor 1998: 28).

It is conceivable that “building upon pre-existing representational schemes in animals” (Hurford 2007: 140), and a general perceptual and cognitive machinery that scaffolded them (Jackendoff 2007: 388), ever increasing linguistic abilities and concepts evolved step by step. They probably did evolve from the proto-concepts we can see in the higher mammals of today into the pre-linguistic concepts that are argued to exist in some of the other great apes (especially those individuals who are enculturated and symbol-trained) and then into some form of proto-language (Bickerton 2009). At some time, this proto-language with already quite sophisticated conceptual representations then evolved into the fully human language we know today.

In summary, a truly human language faculty evolved, which is

(6) a collection of unique mental structures – phonology (externalisation) and syntax (merging constituents (A + B = [AB] and creating blended new ‘mental building blocks’ which can be merged with other constituents recursively [AB] + C = [ABC]) – and the interfaces between these mental structures and the conceptual system. These “specific unique building blocks for phonology, syntax, and their connection to concepts” are what makes language and language acquisition possible (Jackendoff 2007: 388f.).

This account of course has not mentioned important ecological factors (e.g. navigation, foraging, predator avoidance) that will have contributed to these developments and constructed niches in which these factors could develop further and faster. In the case of language, for example both “fast processing and mapping from hierarchical structure to temporal ordering,” which are two fundamentally important features of human language, “can be attributed to progresses in the timing of actions necessary for producing and using hand axes, [as well as throwing] that is, to sensomotoric skills that could have been adapted for language” (Wunderlich 2006). Support for this thesis comes from the fact that PET scans have shown a that there is neural circuitry supporting and involved in both language production and early stone age tool-making (Stout et al. 2008, see also here).

It also fits with our general model that there is mounting evidence “that much temporally sequenced hierarchical structure is constructed by the same part of the brain […] whether the material being assembled is language, dance, hand movements, or music (Jackendoff 2007: 388). Additional work on mirror neurons, motor neurons that activate both when an action is performed and observed (Rizzolatti & Craighero 2004), points in the direction that they are involved in understanding the goal-related actions of others in a social context. The evolution of a Mirror Neuron System for understanding actions and intentions may have been a crucial part of the cognitive development that made human thinking possible.

This is also supported by the fact that the human conceptual system has two distinctive properties: One the one hand it enables abstract, relational, role-governed, symbolic thinking (Penn et al. 2008). But at the same time human concepts are still deeply rooted in, based on, and grounded in embodied sensori-motor experience (Barsalou 1999, Gallese & Lakoff 2005). This holds even for linguistic concepts and metaphors, which have been shown to be partly grounded in embodied cognition (Lakoff & Johnson 1980). To get back to language, a final indicator of the connectedness of social interaction and parts of higher-order cognition comes from proposals that “neural circuits doing computations to control the hierarchy of goal-related actions were ‘exploited’ to serve the newly acquired function of language syntax” (Gallese 2007: 666).

Now that we have some theoretical proposals on crucial aspects of human uniqueness (although this list is far from being definitive and exclusive), we can see in how far they are borne out by the comparative and developmental data that is available.

References:

Aitchison, Jean. 1998. The Articulate Mammal. An Introduction to Psycholinguistics. London / New York: Routledge.

Barsalou, Lawrence W. 1999. “Perceptual Symbol Systems.” Behavioral and Brain Scienes 22.4: 577–609.

Bickerton, Derek (2009): Adams Tongue: How Humans Made Language. How Language Made Humans. New York: Hill and Wang.

Bühler, Karl (1934): Sprachtheorie: Die Darstellungsfunktion der Sprache. Stuttgart: Fischer.

Carruthers, Peter (2002), The cognitive functions of language, in: Behavioral and Brain Sciences, 25 (6),

657–726

Cassirer, Ernst (2006): An Essay on Man: An Introduction to a Philosophy of Human Culture. Hrsg. v. Maureen Lukay. Hamburg: Meiner (Gesammelte Werke. Hamburger Ausgabe. Band 23).

Cheney, Dorothy L. and Robert M. Seyfarth. (2007) Baboon Metaphysics: The Evolution of a Social Mind. Chicago: University of Chicago Press.

Clark, Herbert (1996): Use of Language. Cambridge: Cambridge University Press.

Deacon, Terrence William (1997). The Symbolic Species. The Co-evolution of Language and the Brain. New York / London: W.W. Norton.

Dunbar, R. I. M. and Susanne Shultz. (2007)“Evolution in the Social Brain” Science 317: 1344-1347

Evans, Vyvyan and Melanie Green (2006): Cognitive Linguistics: An Introduction. Edinburgh: Edinburgh University Press.

Fauconnier, Gilles and Mark Turner (2002) The Way We Think: Conceptual Blending and the Mind's Hidden Complexities. New York: Basic Books.

Fodor, Jerry A. (1998) Concepts. Where Cognitive Science Went Wrong. Oxford Congitive Science Series. Oxford: Clarendon.

Gallese, Vittorio (2007). Before and below 'theory of mind': Embodied simulation and the neural correlates of social cognition. Philosophical Transactions of the Royal Society B-Biological Sciences 362 (1480):659-669

Gallese Vittorio, Lakoff George (2005) The Brain’s Concepts: The Role of the Sensory-Motor System in Reason and Language. Cognitive Neuropsychology, , 22:455-479

Graumann, Carl F. (2002): Explicit and Implicit Perspectivity. In: Carl F. Graumann und Werner Kallmeyer (Eds): Perspective and Perspectivation in Discourse. Amsterdam, Philadelphia: John Benjamins Publishing Company, 25-40.

Harder, Peter (fc) Conceptual construal and social construction .

Hurford, James M. (2007): The Origins of Meaning: Language in the Light of Evolution. Oxford: Oxford University Press.

Jackendoff, Ray (2007): Linguistics in Cognitive Science: The State of the Art, The Linguistic Review 24, 347-401.

Lakoff, George, and Mark Johnson (1980) Metaphors we live by. Chicago: University of Chicago Press

Lewin, Roger (2005): Human Evolution: An Illustrated Introduction. Oxford: Blackwell.

Moll, Henrike, & Michael Tomasello. (2007) Co-operation and human cognition: The Vygotskian intelligence hypothesis. Philosophical Transactions of the Royal Society 362: 639-648.

Penn, Derek C, Keith J. Holyoak. and Daniel J. Povinelli (2008): Darwin's mistake: Explaining the discontinuity between human and nonhuman minds. In: Behavioral and Brain Sciences (31:2): 109-130.

Premack, David und Guy Woodruff (1978): Does the Chimpanzee have a

Theory of Mind? In: Behavioral and Bran Sciences 1: 515-526.

Reader, S.M. and K.N. Laland. 2002. “Social Intelligence, innovation, and enhanced brain size in primates” PNAS 99: 4436-4441.

Rizzolatti, Giacomo and Laila Craighero. “The Mirror-Neuron System.” Annual Review of Neuroscience 27 (2004): 169–192.

Searle, John R. (1995): The Construction of Social Reality. New York: Free

Press.

Sperber, Dan and Deirdre, Wilson (1995): Relevance: Communication and Cognition. Second Edition. Malden et al.: Blackwell.

Suddendorf, Thomas & Michael C. Corballis. (2007) The Evolution of Foresight: What is mental time travel, and is it unique to humans? Behavioral and Brain Sciences 30.3: 219-313.

Sterelny, Kim (2003): Thought in a Hostile World: The Evolution of Human Cognition. Malden u.a.: Blackwell.

Stout D., N. Toth , K. Schick, and T. Chaminade (2008): Neural correlates of Early Stone Age toolmaking: technology, language and cognition in human evolution. Proclamations of the Royal Society of London B: Biological. Sciences 363(1499):1939-49.

Tomasello, Michael (2003): Constructing A Language. A Usage-Based Approach. Cambridge, Massachusetts; London, England: Harvard University Press.

Tomasello, Michael (2008): The Origins of Human Communication. Cambridge, MA; London, England: MIT Press.

Tomasello, Michael, Malinda Carpenter, Josep Call, Tanya Behne, and Henrike Moll (2005): Understanding and Sharing Intentions: The Origins of Cultural Cognition. In: Behavioral and Brain Sciences 28:5, 675–691

Tuomela, Raimo (2007): The Philosophy of Sociality: From A Shared Point of View.

Oxford: Oxford University Press.

Tulving, E. 2005. Episodic memory and autonoesis: Uniquely human? In H. S. Terrace, & J. Metcalfe (Eds.), The Missing Link in Cognition (pp. 4-56). NewYork, NY: Oxford University Press.

Quine, Willard van Orman (1960): Word and Object. Cambridge, MA: MIT Press.

Verhagen, Arie (2007): Construal and Perspectivization. In: Dirk Geeraerts and Herbert Cuyckens (eds.) The Oxford Handbook of Cognitive Linguistics. Oxford: Oxford University Press.

Wunderlich, Dieter (2006): “What forced syntax to emerge?” In H.-M. Gärtner et al. (eds.) Between 40 and 60 puzzles for Krifka. ZAS Berlin

Immanuel Kant & Mental Time Travel

In my previous post I pointed out that new evidence coming from the chimpanzee Santino's behavior may be crucial for discussions whether 'episodic' planning and prospective Mental Time Travel exist in non-human animals.

This relates to the proposal by Suddendorf & Corballis (1997, 2007) that Mental Time Travel is unique to humans and that from an evolutionary perspective:

"that the crucial selective advantage mental time travel provides is flexibility in novel situations and the versatility to develop and adopt strategic longterm plans to suit individual selected goals."

Mental Time Tavel thene evolved so we are able to plan future behavior based on the recall of past episodes. But our "episodic memory" only provides the "raw material" for future planning, it isn't useful in itself. From an evolutionary perspective, being able to relive past memories may only be a byproduct, and in itself may not very useful. It's only use might be that it provides us with "raw" material.
Acording to this argument, the crux then is is that our ability to recall past episodes is only a necessary design feature of being able to plan flexibly for the future.
The philosophical implications of such a view may be rather bleak, given that it reduces another of our most cherished features of what makes us human - namely our memories and life histories, which give us a sense of having a, a continous, purpose- and meaningful existence - to an accidental spandrel. But what is also interesting from a philosophical point of view is that Suddendorf & Corballis weren't the first to come up with this idea.

Interestingly, I just found a quote from Immanuel Kant in a paper of a friend of mine:
Recalling the past (remembering) occurs only with the intention of making foresight of the future possible […] we look about us from the standpoint of the present in order to decide something or to be prepared for something. Empirical foresight is the anticipation of similar cases […] and requires no rational knowledge of causes and effects, but only tahe remembering of observed events as they commonly follow one another, and repeated experiences produce n aptitude for it" (Kant, Immanuel. Anthropology from a Pragmatic Point of View. Trans. Robert B. Louden. Cambridge Texts in the History of Philosophy. Cambridge: Cambridge University Press, 2006, 79)

Bibliography:

Kant, Immanuel (2006) Anthropology from a Pragmatic Point of View. Trans. Robert B. Louden. Cambridge Texts in the History of Philosophy. Cambridge: Cambridge University Press.

Suddendorf, T. and M.C. Corballis (1997), Mental time travel and the evolution of the human mind, Genetic Social and General Psychology Monographs 123, pp. 133–167.

Suddendorf. T. and M.C. Corballis (2007), The evolution of foresight: What is mental time travel and is it unique to humans?, Behavioral and Brain Sciences 30, pp. 299–351

---

The Relational Reinterpretation Hypothesis Anno 1840

Last year Penn, Holyoak, and Povinelli published a quite controversial article called "Darwin's mistake: Explaining the discontinuity between human and nonhuman minds."
In it they argued that what is special about human cognition is our innate analogical ability, an ability to reinterpret sensory and cognitve data in terms of abstract relational terms.
The system enabling "higher order, abstract, role-governed, relational reasoning” is grafted on top of our primate cognitive system and explains why our cognitive capacities are so widely different from that of other animals.

The main tenet of this proposal is shared by many researchers, as seen, for example, in Anette Karmilof-Smith's (1992) concept of "Representational Redescription" Hypothesis or Jean Mandler's (2004) "perceptual meaning analysis"

"as the central, attentive process that redescribes attended perceptual information into a simpler and conceptual (accessible) form."

Interestingly, I just found a similar proposal in John Pringle Nichol's "Views of the Architecture of the Heavens" from 1840, although I am quite sure that similar views can be traced much farther back in time :

"We are bound by the inherent necessities of our Being to search for the explanation of every fact or phenomenon, through its relations with some actual order, present or past" (281).

References:

Karmiloff-Smith, Anette (1992): Beyond modularity: A developmental perspective on cognitive science. Cambridge, MA: MIT Press.

Mandler, Jean (2004): A synopsis of The foundations of mind. In: Developmental Science 7:5 , 499–505.

Nichol, John Pringle (1840/1851) Views of the Architecture of the Heavens. London.

Penn, Derek C, Keith J. Holyoak. and Daniel J. Povinelli (2008): Darwin's mistake: Explaining the discontinuity between human and nonhuman minds. In: Behavioral and Brain Sciences (31:2): 109-130.

Proof of Life and some thoughts on human uniqueness

In the next few days I’ll be getting a new laptop and then I’ll finally have access to the internet again. I will try posting on a weekly basis about things going on the blogosphere and about my own attempts at writing my (or rather something equivalent to) my M.A. Thesis.

Right now, I’m reading Marc Hauser’s (2001) “Wild Minds: What Animals Really Think” and Michael Tomasello’s (2003) “Constructing A Language” but I managed to buy Tomasello’s new book, The Origins of Human Communication, have followed Edmund Blair Bolles’ multi-part review with much interest, and when I’m done with the two other books I’ll start with Tomasello’s new one.

As Sandy G. of The Mouse Trap I’m especially interested in Tomasello’s idea of shared intentionality as it unfolds in a joint attentional frame in a rich social interactional setting. But what I am interested in is fleshing out the kind of perspectival cognitive representations that allows us to navigate successfully in social, linguistic, as well as spatial settings.

Apparently, Tomasello again only hints at how such a system might look like, but I share the hunch is that that it has something to do with Bühlerian “coordinate system awareness” and the ability to locate yourself and others in a dynamic shared frame of reference (see also the interesting work of Stephen Levinson)

An abstract frame of reference also seems to be a key issue for our ability of “higher order, abstract, role-governed, relational reasoning” which, according to Penn et al. 2008 (see also here and here) s the core system responsible for setting human cognition apart from the cognitive systems of other animals.

Povinelli et al.’s explanation that the cognitive discontinuity between human and nonhuman cognition arises from our ability of “relational reinterpretation”, i.e. the ability to reinterpret and encode perceptually-based experiences in an abstract and symbolic fashion, still sounds pretty good to me. But their claim rests on the assumption that nonhuman animals aren’t able to build up representations of more abstract frames of references at all, but that that their behaviour can be explained in terms of reinforcement history and perceptually-based strategies, and the evidence cited by them is clearly in favour of their view.

But in Marc Hauser’s 2001 book I’ve read about Clark’s Nutcracker, a food storing bird that can hide up to 33,000 seeds in more than six thousand locations and is able to retrieve most of them months later. Hauser reports on experiments done by Alan Kamil and Juli Jones, who trained the birds to at a point in the middle of two landmarks. After that, the experimenters varied the distance between the landmarks, and the tested Clark’s nutcrackers were successful in generalizing the location of the food to the new geometric situation and retrieved it successfully at the new midway point. Hauser concludes that “these data show that nutcrackers form a representation of the geometric relationship among landmarks – something like the middle – and use this to find stored food” (Hauser 2001: 89).

To me this looks like an instance of relational reinterpretation, reinterpreting the specific perceptually-based spatial location of two landmarks in terms of a higher-order abstract geometrical system, but I would be very interested what other people think about this experiment.


References:

Penn, Derek C, Keith J. Holyoak. and Daniel J. Povinelli (2008): Darwin's mistake: Explaining the discontinuity between human and nonhuman minds. In: Behavioral and Brain Sciences (31:2): 109-130.

Thriller-Writer Lee Child and Linguist Dieter Wunderlich on the Evolution of Language

Lee Child is one of my favorite Thriller-authors. Normally I don’t find the time to read non-studying related fiction, but I especially enjoy his audio books because of the cool American accent of the narrator. However, when I stumbled on an essay by Lee Child called “The Origin of the Thriller”, I was a bit confused. Here’s his take on the evolution of language: According to Lee Child, a couple of hundred thousand years ago, Neanderthals and humans, the only homo “contenders” left were competing for resources, and Neanderthalers had the upper hand:

“They were heavier and stronger and faster. They were superb tool makers. They were much better equipped to survive the brutal conditions of prehistory.

But they didn't survive. We did. Why?

Because Homo Sapiens developed language. Many primitive species could communicate by making sounds — and many still do: prairie dogs make distinctive noises if a predator is spotted — one noise for a ground predator, and another for an airborne predator. But Homo Sapiens went beyond two words. After a random mutation our brains grew large and the new capacity was colonized by language, with a theoretically infinite number of available words, and more importantly with syntax, such that as well as reporting we could plan and speculate. Not just: a predator is coming, but also: a predator will come, or might come. Not just reaction, but also prediction: if we do this, we'll be OK, or if we do that, we'll be in trouble. “

But here’s the gem According to Child, humans are weak and fragile and in disorganized groups we would quickly be killed by predators:

“But a coordinated crowd of two hundred humans is the most powerful animal on earth. The heaviest, the strongest, the hardest to stop, the hardest to kill. Thus, grunting Neanderthals slowly died out, despite their muscle and bone and strength and speed, and talking humans marched on toward the present, despite our slender limbs and fragile skulls”

The last Sentence is faboulus isn’t it? We better don’t tell him anything about Neanderthal-DNA, Neanderthal Vocal Anatomy, FOXP2, Introgression, etc.

But I want to present a more plausible and worked out view on the topic. Yesterday I was searching for material on the evolution of syntax, because a friend of mine asked me to comment on a section of his MA-Thesis in which he shortly discusses the topic. (For a discussion of the speculation, that certain features of language are ‘living fossils’, or vestiges of an older proto-language, see this post).

On my search I found the slides of a talk given by German linguist Dieter Wunderlich on the evolution of language, that he held in Leipzig, Germany, in December 2007. The talk and the slides are in German, but because he offers a very comprehensive and nice review on some aspects of the current state of the art in language evolution research/evolutionary linguistics, I decided to write an English summary of it.

Key Questions

When looking at the evolution of language, there are three question that guide our inquiry:

1. How exactly did language get started? What is hotly debated is whether it evolved in a gradual manner (continuist/adaptationist position: see e.g. Pinker & Bloom 1990) or in a ‘sudden leap’ (discontinuist/ exaptationist: see e.g. Hauser et al. 2002)

2. When did language evolve? Depending on our answer to question 1., the question would be when each step toward language took place, or when the big leap happened.

3. Did language evolve only once or several times?

What is language?

Basically, language can be described as a system for expression, that relates Utterances and meaning to one another, in relation to certain contexts.

Morphosyntax governs the construction of complex utterances out of smallest units of language, namely lexical entries (=”words” in your mental lexicon) as well as morphemes (-s, -ed, un-, -er, etc.). Its system is compositional, that is every construction leads to complex expressions of meaning which are determined by the single lexical entries as well the rules that govern their combination. The rules governing the compositional construction of utterances are recursive.

There are two interfaces to non-linguistic abilities:

1. an interface with the system responsible for the production and perception of sounds and gestures (In generativist terminology this would be the Sensori-Motor System (SM) or the Articulatory-Perceptual (AP) System)

2. an interface with our mental representations and our discourse intentions (in generativist terminology: the Conceptual-Intentional (CI) system. cognitive linguists would probably call it our conceptual system)

Important events which shaped the current state of language

There are 5 important events that have shaped how languages and our mental structures that enable us to use it look:

In chronological Order:

1. There was an expansion of the cortex (frontal lobe) in early hominids such as homo erectus, who lived approx. 2 million years ago. In just 1 million years, brain size rose from 600 to 1400ccm. This may be related to the begin of an ice-age about 2.5 million years ago.

2. Anatomically modern man (homo sapiens) probably evolved about 170.000 years ago in east Africa.

3. Starting from about 50.000 years ago, there is archaeological evidence of improved tool-making capacities, burials, ornaments, and figurative art in several parts of the world (the so-called Upper Palaeolithic Revolution). In Africa these features can be found even earlier, as is especially salient from about 85.000 years ago, which even led some researchers to call this period an “African Upper Palaeolithic” (see e.g. Dubreuil 2008).

4. From 12.000 years ago onwards, there was a spread in agriculture which seemed to have happened independently in several parts of the world (The Neolithic Transition)

5. Starting from 6000 years ago, writing systems were developed independently in several parts of the world.

Of these 5 events, the first three are biological of nature, whereas the last two are cultural events. A diversification of biological events brought about by mutations and selection led to one single event: genetically modern man. In principle, every human being can reproduce with every other opposite-sex human, which fulfils the criterion of biological species. Furthermore, every child, regardless of its parents, can learn every language of the world when it is put into the critical environment at the right age. Thus language is a common and uniting feature of humans, and we all share the genetic structure that enables us to learn language (but for evidence that there is still genetic variation on a small scale, see these two posts)

What are the differences between and non-human communication systems?

Influential linguist Charles F. Hockett has posed 13 ‘design features of language’, 7 of which are especially interesting regarding the evolution of language. These are:

1. For the majority of human languages, the vocal-auditory channel the basic mode of communication.

2. Parity/Interchangeability: hearer and speaker constantly switch roles during conversation, which also means that a communicator is able to both produce and receive the same signal, which isn’t the case with say, gender-specific calls in sticklefish.

3. Semanticity/Arbitrarines: specific signals can be equipped with specific meaning in a manner where there is no necessary or logical connection between form meaning (“table” has nothing to do with any actual properties of a table)

4. Displacement: humans can talk about things that are not present in their immediate environment, or even things that do not exist at all (say, for example, my comprehension of mathematics). Human reference thus extends “beyond the horizon” and the perceptual space, but extends to mental spaces and shared systemic spaces.

5. Honey bee communication about the location of nectar of course is also displaced, but it only built to convey very specific information, and is not unbounded and productive like human language.

6. Traditional Transmission/Learnability human children are able to learn the language of their environment. As W.v.O. Quine said “language is a social art”, which essentially depends on the ability to be part of and interact with a complex culture that transmits complex behavior and knowledge. This complexity and language-specificness is probably the dividing feature, because song-birds also have to learn their songs from other birds, vervet monkeys need to be reinforced in their innate tendencies to hiss at snakes and have to zoom in on the exact referent for eagle alarm callas through positive reinforcements by other group members, and chimpanzees have been shown to adhere to some forms of social transmission and conformity as well as for rational imitation (e.g. Whiten et al. 2005)

7.Discreteness/Duality of Patterning the smallest units of language combine with each other in a systematic and combinatorial manner (that is Phonemes/Sound units combine to form Morphemes) , which then also combine in a systematic fashion (Morphemes built whole words and then sentences). This method allows for “infinite expression by finite means” (Humboldt) and is responsible for the diverse displaced productivity of language.

Wunderlich argues that homo erectus already possessed most of these features, but maybe not 6. and 7.

So what could homo erectus do?

Although he certainly didn’t have full-fledged human language, he was able to perform complex and social tasks. From 1.5 million years ago onwards, he was able to keep a fire burning, and from 0.8 million years ago he could even make fire.

He was able to make hand-axes (1.4 million years ago) and was also able to throw them, which, according to William Calvin, is suggested by neuropaleontological evidence. He way able to hunt together with other group members. He was very mobile: signs of him can be found in Georgia (1.8 million), later on there are also signs in China, Indonesia, and Europe.

Homo erectus was divided in several species that probably lived alongside each other. The last ones co-existing with us were the Neanderthals.

Tool use

Chimpanzees and orangutans use tools (see here, for a cool post on spear fishing in orangutans)such as sticks for termite fishing, stones to crack open nuts, and leaves to soak up water, but these tools are contextually available, that is they do not have to be crafted in the same complex way as hand-axes, for example. Interestingly, there is population level handedness of 2:1 in chimpanzees. Termite fishers are mostly left-handed, whereas nut-crackers and wadge-dippers are mostly right-handed, this means that handedness seems to be heritable. In humans, the left-right ratio is 9:1. The distribution of handedness means that handedness is task-specific, and “

that the motor and cognitive demands of different tasks can have a significant influence on handedness in human and nonhuman primates” (Lanson & Hopkins 2005).

This means

“that antecedents of lateralization of function associated with hand use were present at least 5 million years ago, before the Pan-Homo split,”

and that due to tool-use the human-brain specialized, probably making possible further changes in human neurology and cognitive behaviour (for evidence that there is a neurological link between tool-making and speech, see this post). It is interesting to consider what the cognitive preconditions were that enabled tool-making. The Oldowan technique, which

can be found from 2.6 million years ago. This technique is used to make cutting tools by breaking off sharp-edged flakes from a larger stone. This is achieved by striking a core stone with a hammerstone, thereby knocking flakes from the core (see Ambrose 2001).

This technique definitely requires intentional planning that isn’t bound to the here-and-now, but directed at the future. Also, and more important for language, it requires the ability for complex propositional thought. Thus the following conscious key cognitive mechanisms found in language are also necessary for tool-making and thus already existed 2.6 million years ago:

1. Predication: the same referent (core stone), can be subject of different predications, a structure that can be called “Topic-Comment”-structure (see also this post):

George (Topic) is eating brains (Comment) / George (Topic) is a Zombie (Comment) / George (Topic) is (Comment).

2. Qualification of predications that have already been made and higher-order temporal hierarchical ordering.

To wit, what this basically means is that both in linguistics and tool-making you first have an initial structure which you change by commenting/acting on it. This new structure can then be the topic of new comments or actions, and the new structure arising from these computations/ actions can again be the topic of new predications and ad infinitum. Consider for example the sentence: The living homeless, who wanted money, had infested South Park, but then they went to California

A hierarchical behavioral sequence like toolmaking seems to have similar properties:

I don’t know about you, but for me this looks like recursion, the only difference being that for toolmaking the recursive operation are applied to a physical object, and for language they are applied to a mental object. However, if toolmaking requires intentional planning, there had to be at least some recursive mental operations that in mental action planning. This would mean that, pace Hauser et al. (2002), recursion is neither special to language nor recently evolved.

As Wunderlich writes in his (2006) paper “What forced syntax to emerge?”

"Both fast processing and mapping from hierarchical structure to temporal ordering, two other fundamental features of human language, can be attributed to progresses in the timing of actions necessary for producing and using hand axes, [as well as throwing] that is, to sensomotoric skills that could have been adapted for language.”

All this is made all the more exciting by converging evidence that combinatorial and hierarchical structure of any kind (be it linguistic, cognitive, or sensori-motor are constructed by the same part of the brain and via the same mechanisms:

“Similarities exist between the architecture for sentence structure and blackboard architectures for combinatorial structures in visual cognition, derived from the structure of the visual cortex” (van der Velde & de Kamps 2006: 1)

“Evidence is mounting that much temporally sequenced hierarchical structure is constructed by the same part of the brain – roughly Broca’s area and subcortical areas connected to it – whether the material being assembled is language, dance (Lieberman 2005: 297), hand movements (Lieberman 2005: 294; Wilkins 2005: 279), or music (Patel 2003). Nor, within language, is Broca’s area confined to syntax, as often asserted: it also appears to play a role in phonological and semantic combinatoriality, possibly in distinct though overlapping subareas (Hagoort 2005; Poeppel and Embick 2005)" (Jackendoff 2007: 388)

“On the basis of all these results, it can be hypothesized that [the recursive morphosyntax of modern language] is the computational output of a cortical premotor network originally evolved to control/represent the hierarchical structure of goalrelated action When in evolution, selective pressure led to the emergence of language, the same neural circuits doing computations to control the hierarchy of goal-related actions were ‘exploited’ to serve the newly acquired function of language syntax. A similar functional overlap between action and language acquisition is indeed evident during children’s development, i.e. children parallel their capacity to master hierarchical complexity both in the domain of language and goal-related action.“ (Gallese 2007: 666)”

That’s it for today. In my next post I will continue my summary of Wunderlich’s presentation.

References:

Ambr Ambrose, Stanley H. 2001. Paleolithic Technology and Human Evolution. Science 291, no. 5509 (March 2): 1748-1753. doi:10.1126/science.1059487.

Dubreuil, Benoît (2008): “What do modern behaviours in Homo sapiens imply for the evolution of language?”, in A. D. M. Smith, K. Smith, and R. Ferrer i Cancho (eds.), The Evolution of Language. Proceedings of the 7th International Conference (Evolang 7), World Scientific, 99-106.

Gallese, Vittorio (2007). Before and below 'theory of mind': Embodied simulation and the neural correlates of social cognition. Philosophical Transactions of the Royal Society B-Biological Sciences 362 (1480):659-669

Hagoort, Peter (2005). On Broca, brain, and binding: a new framework. Trends in Cognitive Sciences 9: 416–423

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.

Jackendoff, Ray (2007): Linguistics in Cognitive Science: The State of the Art, The Linguistic Review 24, 347-401.

Lieberman, Phillip (2005): The pied piper of Cambridge. The Linguistic Review 22: 289–302.

Lonsdorf, Elizabeth V., and William D. Hopkins. 2005. Wild chimpanzees show population-level handedness for

tool use. Proceedings of the National Academy of Sciences 102, no. 35 (August 30): 12634-12638. doi:10.1073/pnas.0505806102.

Patel, Aniruddh D. (2003). Language, music, syntax, and the brain. Nature Neuroscience 6: 674– 681.

Pinker, Steven & Paul Bloom (1990). “Natural Language and Natural Selection.” In: Behavioral and Brain Sciences 13.4: 707-726.

Poeppel, David, and David Embick (2005). Defining the relation between linguistics and neuroscience. In Twenty-first century psycholinguistics: Four cornerstones, A. Cutler (ed.), Hillsdale, NJ: Erlbaum.

Van der Velde, F. & de Kamps, M. (2006). Neural blackboard architectures of combinatorial structures in cognition. In: Behavioral and Brain Sciences, 29, 1-72.

Whiten, Andrew, Victoria Horner & Frans B. M. de Waal. 2005. “Conformity to Cultural Norms of Tool Use in Chimpanzees.” Nature 437: 737-740.

Wilkins, Wendy K. (2005). Anatomy matters. The Linguistic Review 22: 271–288.

Wunderlich, Dieter (2006): “What forced syntax to emerge?” In H.-M. Gärtner et al. (eds.) Between 40 and 60 puzzles for Krifka. ZAS Berlin