March 25th and 26th, 2015

organized by Willem Zuidema

 

Special theme: the coevolution of biology and culture

Natural language is an extremely complex and varied phenomenon and very different from both other human cognitive functions and animal communication. Yet, at the level of genes, brain structures, anatomy and basic learning procedures the mechanisms supporting language and speech are not so clearly language-specific. How can the conflict between evidence pointing to biological continuity and evidence for the uniqueness of language be resolved? In this workshop experts from animal behaviour, linguistics, psychology, human genetics and computational modelling review evidence from variety of fields about the biological and cultural evolution of language and speech. The workshop will end with a general discussion where we will critically assess the popular theory that coevolution of biology and culture plays a key role in resolving the conflict.

Invited Speakers:

Bill Thompson (Brussels)
Jennifer Culbertson (Edinburgh)
Asli Ozyurek (MPI Nijmegen)
Arie Verhagen (Leiden)
Simon Fisher (MPI Nijmegen)
Tecumseh Fitch (Vienna)
Carel ten Cate (Leiden)
Simon Kirby (Edinburgh)
Kenny Smith (Edinburgh)
Bart de Boer (Brussels)
Olga Fehér (Edinburgh)
Dan Dediu (MPI Nijmegen)
Johan Bolhuis (Utrecht)
Louis-Jean Boë (Grenoble)

Program

Day 1 (March 25th)

9.00 Doors open
9.30 Bill Thompson (Brussels): “Introduction Workshop Theme: Coevolution of Culture and Biology”
10.05 Bart de Boer (Brussels): Culture-biology coevolution in a finite population
10.40 coffee
11.10 Louis-Jean Boë (Grenoble): The exaptation as a determinant for emergence of speech
11.45 Dan Dediu (MPI Nijmegen): Shaping each other: language and speech in their wider context
12.20 lunch break (on your own)
14.00 Johan Bolhuis (Utrecht): How could language have evolved? A comparative approach.
14.35 Asli Ozyurek (MPI Nijmegen): The role of gesture in language evolution: Beyond the gesture-first hypotheses
15.10 coffee
15.40 Tecumseh Fitch (Vienna): How to build a human brain from primate parts
16.15 Discussion
16.45 Closing
17h00-20h Plenary program conference (drinks, keynote by Ray Jackendoff;
discussion with Simon Kirby, Tecumseh Fitch and others).

 

Day 2 (March 26th)

9.00 Doors open
9.30 Simon Kirby (Edinburgh): From Item to System: Structure as an Inevitable Consequence of Cultural Evolution
10.05 Olga Fehér (Edinburgh): Self-training in zebra finches reveals genetically and environmentally determined aspects of song
10.40 Coffee
11.10 Carel ten Cate (Leiden): Cultural transmission of birdsong and song divergence (or not) – a tale of two species.
11.45 Arie Verhagen (Leiden): Public and private communication: Stages in the evolution of language
and cognition?
12.20 lunch break (on your own)
14.00 Jennifer Culbertson (Edinburgh): Soft biases for word order in adults and children: implications for the language faculty
14.35 Kenny Smith (Edinburgh): The evolution of language and the language faculty
15.10 coffee
15.40 Simon Fisher (MPI Nijmegen): Language, Evolution, and the Genomics Revolution
16.15 Discussion
16.45 Closing
17h00-19h Plenary program conference (drinks, keynote by Andreas Roepstorff).

Abstracts:

Culture-biology coevolution in a finite population
Bart de Boer (Brussels)

I will present a mathematical model of co-evolution of culture and biology in small populations. It turns out that even when culture changes rapidly, biological adaptations to arbitrary cultural traits can become established in a population. I will discuss the interpretation of these results for the study of language evolution.

The exaptation as a determinant for emergence of speech
Louis-Jean Boë (Grenoble)

• How the vocal tract takes advantage of some of the general acoustic properties of tubes
• How the anatomy of lips and tongue predisposes the primates to produce differentiated vocalizations
• How functions like sucking, lip smacking and food transportation could have been recovered for developing appropriate control of the vocal tract
• How this knowledge and these hypotheses allow to better understand the phylogenesis and the ontogenesis of the speech

Shaping each other: language and speech in their wider context
Dan Dediu (MPI Nijmegen)

Language and speech cannot be understood outside their wider evolutionary context, which include biology and culture, and must be seen as part of a complex co-evolutionary processes that has been active throughout most of human evolution. In this talk I will survey the foundations and consequences of this process, on the way introducing some examples of gene-culture co-evolution, and focusing specifically on one side of this co-evolutionary cycle, namely biology (and the environment) influencing language and, in particular, speech.

How could language have evolved? A comparative approach.
Johan J. Bolhuis (Cognitive Neurobiology, Department of Psychology, Utrecht University)

A major stumbling block for the comparative analysis of language evolution is that, so far, there is no evidence for human-like language syntax in any non-human species. There is no a priori reason why a version of such a combinatorial computational system could not have evolved in non-human animals, either through common descent (e.g., apes) or convergent evolution (e.g., songbirds). Although the auditory-vocal domain is just one possible external interface for language (with signing being another), it could be argued that the strongest animal candidates for human-like syntax are songbirds and parrots. This is because they exhibit vocal imitation learning, a trait that is shared with certain marine mammals and hummingbirds, but that appears to be absent in our closest relatives, the great apes. There are striking behavioural similarities between auditory-vocal learning in human infants and in songbirds. In both cases, auditory learning takes place during a sensitive period early in development, and there is a transitional period of early vocalisation which is called ‘babbling’ in humans and ‘subsong’ in birds. There are also analogies with regard to the neural organisation of auditory memory and vocal production. Songbirds appear to have ‘Broca-like’ brain regions involved in the production of song as well as in sensorimotor learning, and ‘Wernicke’like’ regions involved in auditory perception and memory. Furthermore, these regions exhibit patterns of hemispheric lateralisation that are very similar to those in human speech- and language related regions. Finally, there are interesting parallels regarding certain genes that are involved in vocalisation. In addition, like human spoken language, birdsong involves patterned vocalisations that can be quite complex, with a set of rules that govern variable song element sequences known as ‘phonological syntax’. Contrary to recent suggestions, to date there is no evidence to suggest that birdsong patterns exhibit the hierarchical syntactic structure that characterizes human language, or any mapping to a level forming a language of thought, as in humans.

Considering the evidence, an evolutionary scenario emerges where three factors are important. First, there is neural homology, where similar brain regions are involved in auditory learning and vocal production, not only in songbirds and humans, but also in other mammals. Second, there is evolutionary convergence with regard to the mechanisms of auditory-vocal learning, which proceeds in essentially the same way in songbirds and human infants, but not in non-human primates. Third, as yet there is no evidence to suggest that non-human animals possess the combinatorial complexity of human language syntax. It may be that the neural mechanisms that evolved from a common ancestor, combined with the auditory-vocal learning ability that evolved in both humans and songbirds, contributed to the emergence of language uniquely in the human lineage.

The role of gesture in language evolution: Beyond the gesture-first hypotheses
Asli Ozyurek (MPI Nijmegen)

It has been a popular view to propose that gesture preceded and paved the way for the evolution of (spoken) language (e.g., Corballis, Tomasello, Arbib). However these views do not take into account the recent findings on the neural and cognitive infrastructure of how modern humans (adults and children) use gestures in various communicative contexts. Based on this current knowledge I will revisit gesture-first theories of language evolution and discuss alternatives more compatible with the multimodal nature of modern human language.

How to build a human brain from primate parts
Tecumseh Fitch (Vienna)

From Item to System: Structure as an Inevitable Consequence of Cultural Evolution
Simon Kirby (Edinburgh)

A series of laboratory experiments recreating the cultural evolution of language have suggested that the systematic structure of language arises as a natural consequence of the way language is transmitted through generations of learners. To what extent is this cumulative evolution of structured behavior specific to language, and could it be an artifact of the way in which our experiments are designed? In this talk, I will present two recent experimental studies that are framed entirely non-linguistically, but nevertheless involve the transmission over generations of learners of complex behaviors. One uses human participants, and another a population of baboons. In both, we see the cumulative evolution of structured behavior. I will suggest that there may be a universal law of cultural evolution that means we should expect sets of independently copied behaviors to transform over generations into interdependent systems of behaviors of the sort we see in language. I will end the talk with some thoughts about where this leaves the question of human uniqueness and the biological prerequisites for language.

Self-training in zebra finches reveals genetically and environmentally determined aspects of song
Olga Fehér (Edinburgh)

Birdsong, like language, is socially learned, culturally transmitted, exhibits structure on multiple levels, and it is contingent upon rich social and acoustic input during development. In this study, we raised juvenile birds in social isolation but exposed to their own developing songs. Despite marked family effects, self-trained birds crystallised on more normal and rhythmic songs than their brothers raised in acoustic isolation. This study allowed us to differentiate between aspect of song that are genetically determined and those that are influenced by the acoustic and social environment.

Cultural transmission of birdsong and song divergence (or not) – a tale of two species.
Carel ten Cate (Leiden)

Many songbirds learn their songs from conspecifics, resulting in cultural transmission. In some cases this may lead to differences in songs between neighbouring populations and one might expect this also to be reflected on larger scale with songs drifting away from each other when populations become more separated from each other. Yet, this is not always the case. In this presentation I will discuss studies on two species, the chaffinch and the zebra finch, for which there is extensive knowledge about the song learning processes as well as the song differentiation between different populations.

Public and private communication: Stages in the evolution of language and cognition?
Arie Verhagen (Leiden)

In a series of studies, Tomasello has laid out a comprehensive theory of the evolution of both human language and human cognition, and how the two are connected. Tomasello (2009) and especially (2014) explicitly defend a two-stage model that was still somewhat implicit in Tomasello (2008): The evolution of human mutualistic cooperation and communication – ‘private’ cooperative communication between specific individuals (having been) engaged in one or more collaborative projects – preceded the evolution of group level practices of cooperation and communication: ‘public’ language and culture. Cognitively: “joint” intentionality emerged first and evolved into what is essentially still its present state, which set the stage for the subsequent evolution of “collective” intentionality (Tomasello 2014). An alternative scenario is that these two kinds of processes and capacities evolved more ‘in tandem’: A gradual increase in the role of culture (learned patterns of behaviour) produced differences and thus competition between groups of (proto‑)humans, which in turn provided selection pressures for an increased capability and motivation of individuals to engage in collaborative activities with others (cf. Boyd & Richerson 2006).
A consequence of the two-stage view is that argumentative language use and explicit reasoning, including the use of negation and conditional constructions, are seen as belonging entirely to the second stage (Tomasello 2014: 107ff). Indeed, Tomasello (2014) depicts argumentation as an advanced form of language use, developed and practised in the context of public debates. However, linguistic research suggests that all language use, including basic conversation, is fundamentally argumentative, in the sense of evoking multiple viewpoints (as with the use of negation) and proposing ways of deciding between them (Verhagen 2008, 2015; cf. also Mercier & Sperber 2011). In terms of linguistic regularities, a public debate and a two party conversation do not differ fundamentally (the difference seems to be more one of explicit awareness). Although not decisive, such a lack of systematic reflexes of the assumed two stages, in the structure of present day languages supports the cultural group selection scenario more than the two-stage scenario.
Moreover, taking the public character of linguistic communication as basic provides a way of resolving a problem of infinite regress. In the ‘cascade’ of selective processes described by Hurford (2007: 304), mutualistic cooperation and reciprocal altruism require an ability of recursive mind reading – which may go on indefinitely – but the alternative scenario does not: the assumption that the cultural values of symbols (systematic patterns of communicative behaviour) are universally accessible (in the group) suffices. The scenario of cultural group selection may thus be less demanding of cognitive resources than the two-stage view. In fact, it may well have provided the basis for the evolution of recursive mind reading, by creating patterns of behaviour that allow for analysis in these terms in certain circumstances even if they have not been produced by it – an instance of the idea that the emergence of novel, more complex cognition may be facilitated by relevant structure in the external environment that emerges for independent reasons (cf. Zuidema & Verhagen 2010).

• Verhagen, Arie (2008). Intersubjectivity and the architecture of the language system. In: Jordan Zlatev, Timothy P. Racine, Chris Sinha and Esa Itkonen (eds.). The Shared Mind: Perspectives on Intersubjectivity. Amsterdam/Philadelphia: John Benjamins Publishing Company, 307–331.
  Verhagen, Arie (2015). Grammar and Cooperative Communication. In: Ewa Dabrowska & Dagmar Divjak (eds.), Handbook of Cognitive Linguistics. Berlin/‌Boston: De Gruyter Mouton, 232–251.
  Boyd, R. & P.J. Richerson (2006). Culture and the Evolution of the Human Social Instincts. In S.C. Levinson & N.J. Enfield (eds.), Roots of Human Sociality. Culture, Cognition and Interaction. Oxford/New York: Berg, p.453-477.
  Hurford, James R. (2007). The Origins of Meaning. Oxford: Oxford University Press.
  Mercier, Hugo & Dan Sperber (2011). Why do humans reason? Arguments for an argumentative theory. Behavioral and Brain Sciences 34: 57–111.
  Tomasello, Michael (2008). Origins of Human Communication. Cambridge, MA/London: MIT Press.
  Tomasello, Michael (with Carol Dweck, Joan Silk, Brian Skyrms, and Elizabeth Spelke) (2009). Why We Cooperate. Cambridge MA/‌London: Harvard University Press.
  Tomasello, Michael (2014). A Natural History of Human Thinking. Cambridge, MA/‌London: Harvard University Press.
  Zuidema, Willem & Arie Verhagen (2010). What are the unique design features of language? Formal tools for comparative claims. Adaptive Behavior 18: 48-65.

Soft biases for word order in adults and children: implications for the language faculty
Jennifer Culbertson (Edinburgh)

I present evidence of four biases impacting nominal word order learning in adults and children. These biases parallel asymmetries found in typological data which have been used to argue for special properties of the linguistic system. I discuss the nature of these biases and their implications for the evolution of the language faculty.

The evolution of language and the language faculty
Kenny Smith (Edinburgh)

Languages are socially learnt and culturally transmitted, and evolve as a result. I will present a mix of experiments and models which suggest that the cultural evolution of language has profound implications for our understanding of the human language faculty and its evolution; in particular, our default expectation should be that the language faculty consists of weak, defeasible or domain-general biases, rather than strong constraints on the types of languages that can be learnt.

Language, Evolution, and the Genomics Revolution
Simon Fisher (MPI Nijmegen)

With recent dramatic advances in molecular methods, scientists are starting to decipher how our genome helps to build a language-ready brain. I will describe how language-related genes can provide functional windows into the critical neural pathways. Intriguingly, our first glimpses into the relevant mechanisms suggest that this capacity, while unique to humans, is built on neurogenetic systems that are evolutionarily ancient. I will illustrate this point by considering the private life of the FOXP2 gene.

Some key papers:

Culbertson & David. (2013). Language learners privilege structured meaning over surface frequency. Proceedings of the National Academy of Sciences, 111(16):5842–5847. (pdf)

Ozyurek, A. (2014). Hearing and seeing meaning in speech and gesture: Insights from brain and behaviour. Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences, 369(1651): 20130296 (pdf)

Fisher, S. E., & Vernes, S. C. (2014). Genetics and the Language Sciences. Annual Review of linguistics (pdf)

Verhagen, Arie (2015). Grammar and Cooperative Communication. In: Ewa Dabrowska & Dagmar Divjak (eds.), Handbook of Cognitive Linguistics. Berlin/‌Boston: De Gruyter Mouton, 232–251.

Tecumseh Fitch, W. “Toward a computational framework for cognitive biology: Unifying approaches from cognitive neuroscience and comparative cognition.” Physics of Life Reviews (2014). (pdf)

Claidiere, N., Smith, K., Kirby, S. & Fagot, J. 2014. Cultural evolution of a systematically structured behaviour in a non-human primate. Proceedings of the Royal Society B 281;2014-1541.

ten Cate, C. & Okanoya, K. 2012. Revisiting the syntactic abilities of non-human animals: natural vocalizations and artificial grammar learning. Philosophical Transactions of the Royal Society B 367;1984-1994.

Fehér, O., Wang, H., Saar, S., Mitra, P. P., Tchernichovski, O. (2009). De novo establishment of wild-type song culture in the zebra finch. Nature, 459, 564-568.

de Boer, Bart (2012) Loss of air sacs improved hominin speech abilities. Journal of Human Evolution 62(1) 1–6

Smith, K. (2011). Learning bias, cultural evolution of language and the biological evolution of the language faculty. Human Biology, 83, 261-278.

Dediu, D. (in press). An introduction to genetics for language scientists: Current concepts, methods, and findings. Cambridge: Cambridge University Press.

Zuidema, W. (2013). Language in Nature: on the Evolutionary Roots of a Cultural Phenomenon. In: Philippe Binder and Kenny Smith (eds.), The Language Phenomenon, Berlin: Springer

Bolhuis, J.J., Tattersall, I., Chomsky, N. & Berwick, R.C. (2014). How could language have evolved? PLoS Biology, 12(8)

Kirby, S., Cornish, H. & Smith, K. (2008). Cumulative cultural evolution in the laboratory: An experimental approach to the origins of structure in human language. Proceedings of the National Academy of Sciences -USA 105(31);10681-10686

Boë, Louis-Jean and Granat, Jean and Heim, Jean-Louis and Badin, Pierre and Barbier, Guillaume and Captier, Guillaume and Serrurier, Antoine and Perrier, Pascal and Kielwasser, Nicolas and Schwartz, Jean-Luc (2013). Reconstructed fossil vocal tracts and the production of speech. Phylogenetic and ontogenetic considerations. New perspectives on the origins of language.