Convergent Cultural Evolution Research Articles

Cartography: Innateness or Convergent Cultural Evolution?

Haspelmath argues that linguists who conduct comparative research and try to explain patterns that are general across languages can only consider two sources of these patterns: convergent cultural evolution of languages, which provides functional explanations of these phenomena, or innate building blocks for syntactic structure, specified in the human cognitive system. This paper claims that convergent cultural evolution and functional-adaptive explanations are not sufficient to explain the existence of certain crosslinguistic phenomena. The argument is based on comparative evidence of generalizations based on Rizzi and Cinque's theories of cartographic syntax, which imply the existence of finely ordered and complex innate categories. I argue that these patterns cannot be explained in functional-adaptive terms alone.

Replaying history’s tape: Convergent cultural evolution and the prospects of humanity after a social collapse

A global catastrophe, such as an all-out thermonuclear war, may bring about the collapse of human civilization. The normative evaluation of such an outcome ought to consider (among other possibilities) the probability of the re-emergence of modern civilization after such an event and how soon such re-emergence could take place. In theoretical biology, a discussion relevant to this consideration has taken place between proponents of the “robustness thesis,” according to which the history of life is robust with regard to change, and the “fragility thesis,” according to which the history of life is contingent on specific conditions. Here, I discuss whether instances of cultural convergent evolution can be used to defend a robustness thesis about human history. In other words, should we expect that history will repeat itself after a collapse (or a “replaying of history’s tape”)? I also discuss the extent to which degrees of freedom with regard to cultural practices can inform these considerations. I argue that (1) we have no evidence that suggests that a modern and industrialized civilization is likely to re-emerge in a “replay” scenario and (2) that if such a re-emergence were to take place, it would likely occur later rather than sooner.

Human Linguisticality and the Building Blocks of Languages.

This paper discusses the widely held idea that the building blocks of languages (features, categories, and architectures) are part of an innate blueprint for Human Language, and notes that if one allows for convergent cultural evolution of grammatical structures, then much of the motivation for it disappears. I start by observing that human linguisticality (=the biological capacity for language) is uncontroversial, and that confusing terminology (“language faculty,” “universal grammar”) has often clouded the substantive issues in the past. I argue that like musicality and other biological capacities, linguisticality is best studied in a broadly comparative perspective. Comparing languages like other aspects of culture means that the comparisons are of the Greenbergian type, but many linguists have presupposed that the comparisons should be done as in chemistry, with the presupposition that the innate building blocks are also the material that individual grammars are made of. In actual fact, the structural uniqueness of languages (in lexicon, phonology, and morphosyntax) leads us to prefer a Greenbergian approach to comparison, which is also more in line with the Minimalist idea that there are very few domain-specific elements of the biological capacity for language.

Cross-cultural invariances in the architecture of shame

Human foragers are obligately group-living, and their high dependence on mutual aid is believed to have characterized our species' social evolution. It was therefore a central adaptive problem for our ancestors to avoid damaging the willingness of other group members to render them assistance. Cognitively, this requires a predictive map of the degree to which others would devalue the individual based on each of various possible acts. With such a map, an individual can avoid socially costly behaviors by anticipating how much audience devaluation a potential action (e.g., stealing) would cause and weigh this against the action's direct payoff (e.g., acquiring). The shame system manifests all of the functional properties required to solve this adaptive problem, with the aversive intensity of shame encoding the social cost. Previous data from three Western(ized) societies indicated that the shame evoked when the individual anticipates committing various acts closely tracks the magnitude of devaluation expressed by audiences in response to those acts. Here we report data supporting the broader claim that shame is a basic part of human biology. We conducted an experiment among 899 participants in 15 small-scale communities scattered around the world. Despite widely varying languages, cultures, and subsistence modes, shame in each community closely tracked the devaluation of local audiences (mean r = +0.84). The fact that the same pattern is encountered in such mutually remote communities suggests that shame's match to audience devaluation is a design feature crafted by selection and not a product of cultural contact or convergent cultural evolution.

Dialects of an invasive songbird are preserved in its invaded but not native source range

Biological invasions are not only events with substantial environmental and socioeconomic impacts but are also interesting natural experiments, allowing the study of phenomena such as the cultural evolution of bird song following introduction. We took an excellent opportunity to compare the distribution of dialects of the yellowhammer Emberiza citrinella, a small Eurasian passerine, in its native source region (Great Britain) and invaded range (New Zealand) more than hundred years after relocation. Recent field recordings (including those provided by volunteers within a citizen science project) were complemented by those from archives, each assigned to appropriate dialect by visual inspection of a sonogram, and the resulting spatial patterns of dialect distribution were interpreted using historical data on the yellowhammer invasion. The two countries differ markedly in the composition and distribution of dialects. New Zealand populations sing a greater number of different dialects, seven in total, five of which were not detected in the current British population, but have been reported by previous studies from the continental Europe. Two identified localities of capture (Brighton, Sussex, UK) and release (Dunedin, Otago, NZ) differ even more strikingly, having no dialects in common. The largely sedentary nature of yellowhammers allows for two mutually exclusive explanations for European dialects being detected in New Zealand but not in Great Britain: 1) the corresponding song types have emerged de novo in New Zealand, through convergent cultural evolution; 2) the dialects have disappeared from Great Britain, while being preserved in New Zealand. Indirect evidence from the widespread occurrence of these dialects in continental Europe and the reported stability of yellowhammer song, supports the latter explanation. We suggest that the yellowhammer dialect system is an avian equivalent of a phenomenon already noted in human languages, in which ancient words or structures are retained in expatriate communities.

The origin of the Gravettian

The Gravettian is an Upper Palaeolithic unit that had a pan-European range. Unlike the Aurignacian, it did not extend beyond Europe. In terms of taxonomy, in a polythetic system, the Gravettian can be placed on various levels. In terms of material culture and lithic inventories, it is closer to the concept of a “technocomplex”, while in terms of symbolic culture it corresponds to the concept of “archaeological culture”. These differences in the degree of the correlation of particular socio-cultural sub-systems have caused emphasis to be placed either on unifying elements, or on differentiating components.These different viewpoints on the Gravettian have resulted in various hypotheses of the origins of this complex. These hypotheses take into account:a) monocentric origin from Danubian centers, from which the Gravettian spread to the west giving rise to the “western European Perigordian”, and to eastern Europe where it gave rise to the Kostienkian (the Kostienki–Avdeyevo culture). This hypothesis is most frequently proposed.b) polycentric origins that assume other centers of autonomous formation of the Gravettian (e.g. eastern European and middle Mediterranean centres).c) origins related to cultural adaptations that led to convergent cultural evolution in various territories in consequence of environmental changes, notably in the younger part of MIS 3.None of these hypotheses seems to fully explain the processes of the emergence of the Gravettian. It is only a combination of these hypotheses that enables a more penetrating understanding of the process of cultural evolution in the Middle Upper Palaeolithic in Europe.Doubtless, the Gravettian is a varied unit in a number of aspects. Nevertheless, similarities do exist in respect of numerous elements of technology, morphology of lithic and bone implements, symbolic culture, behaviours related to food procurement, and the broad sphere of inter-group contacts and zones of raw material procurement. In the Gravettian, a number of elements are herbingers of the “Neolithic revolution”: the semi-settled way of life (multiseasonal settlements), intentionally designed lay-out of villages, the use of fired clay, the building of complex dwelling structures, and the use of plant foods.

Is “Huh?” a Universal Word? Conversational Infrastructure and the Convergent Evolution of Linguistic Items

A word like Huh?–used as a repair initiator when, for example, one has not clearly heard what someone just said– is found in roughly the same form and function in spoken languages across the globe. We investigate it in naturally occurring conversations in ten languages and present evidence and arguments for two distinct claims: that Huh? is universal, and that it is a word. In support of the first, we show that the similarities in form and function of this interjection across languages are much greater than expected by chance. In support of the second claim we show that it is a lexical, conventionalised form that has to be learnt, unlike grunts or emotional cries. We discuss possible reasons for the cross-linguistic similarity and propose an account in terms of convergent evolution. Huh? is a universal word not because it is innate but because it is shaped by selective pressures in an interactional environment that all languages share: that of other-initiated repair. Our proposal enhances evolutionary models of language change by suggesting that conversational infrastructure can drive the convergent cultural evolution of linguistic items.

Song convergence in multiple urban populations of silvereyes (Zosterops lateralis).

Recent studies have revealed differences between urban and rural vocalizations of numerous bird species. These differences include frequency shifts, amplitude shifts, altered song speed, and selective meme use. If particular memes sung by urban populations are adapted to the urban soundscape, “urban-typical” calls, memes, or repertoires should be consistently used in multiple urban populations of the same species, regardless of geographic location. We tested whether songs or contact calls of silvereyes (Zosterops lateralis) might be subject to such convergent cultural evolution by comparing syllable repertoires of geographically dispersed urban and rural population pairs throughout southeastern Australia. Despite frequency and tempo differences between urban and rural calls, call repertoires were similar between habitat types. However, certain song syllables were used more frequently by birds from urban than rural populations. Partial redundancy analysis revealed that both geographic location and habitat characteristics were important predictors of syllable repertoire composition. These findings suggest convergent cultural evolution: urban populations modify both song and call syllables from their local repertoire in response to noise.

Contextualisation and typology of disc-headed and trapezoidal gravemarker forms in Scotland

Two distinctive small funerary artefact types, disc-headed and trapezoidal gravemarkers, are described. Both are uncommon in Scotland. Small disc-headed gravemarkers are distributed throughout the country but, with two exceptions, trapezoidal gravemarkers are restricted to the Shetland Islands. All known examples of these objects, including some not previously reported, are detailed and discussed in the context of similar artefacts in the rest of Britain and Europe. The current confusion in the use of names for these marker types and their variants is addressed and, through the construction of two separate typologies, a practical taxonomy is suggested. It is also suggested that both these gravemarker forms may represent examples of convergent cultural evolution.

Convergent cultural evolution and multilevel selection: Reply to comments on Janet Landa’s ‘The bioeconomics of homogenous middleman groups as adaptive units: Theory and empirical evidence viewed from a group selection framework’

The comments on Janet Landa’s (J Bioecon 10(3):259–278, 2008) target article provide a fascinating snapshot of how multilevel selection theory is perceived across several disciplines. When we focus on the zone of agreement among the commentators, Landa’s article provides an important example of convergent cultural evolution. When we focus on the zone of disagreement, we find a snapshot of the current status of the group selection controversy that goes beyond narrow scientific issues and requires a ‘truth and reconciliation’ process to resolve, as discussed in my series of blogs titled “Truth and Reconciliation for Group Selection” (Wilson http://www.huffingtonpost.com/david-sloan-wilson/#blogger_bio, 2009) and briefly summarized here.

Genes and homogeneous trading groups: A comment on Janet Landa’s target paper

In her target paper Janet Landa (2008) presents compelling evidence that cultural group strategies are a major factor underlying the development and continuity of ethnically homogeneous middleman trading groups (HMGs). HMG traders pass on the values and institutions underlying within-group trust and punishment of free-riders which in turn makes the group successful in risky markets. Landa finds that despite geographical separation the same HMG strategy has been adopted by different ethnic groups to guarantee contracts in societies with weak contract law. The finding of convergent cultural evolution is an important contribution to our knowledge of this subject. I appreciate Landa’s autobiographical approach. She recounts the development of her analysis beginning with her theory of ethnically homogeneous middleman groups as club-like trading institutions for contract enforcement in the early 1980s, followed by the incorporation of signaling theory, then HMGs as cultural transmission units in early 1990s, and finally her conceptualization of HMGs as adaptive units within the frame of multilevel-selection theory. I find it significant that althoughLanda’s analysis relies ongene-culture co-evolution theory it does not explore biological factors. Landa realizes that such factors must be included in a comprehensive theory (Footnote 5) but chooses to focus on cultural causes. In this comment I discuss some ways in which the analysis might be rounded out to include behavioral biological factors and suggest how these contribute to the success and continuity of HMGs. Landa’s analysis provides some of the evidence needed to make this case. Let us take a closer look at some key concepts, starting with ‘adaptation’. The definition Landa quotes from Ghiselin entails survival and reproduction, which could

Convergent cultural evolution may explain linguistic universals

AbstractChristiansen & Chater's (C&C's) argument rests on an assumption that convergent cultural evolution can produce similar (complex) behaviours in isolated populations. In this commentary, I describe how experiments recently carried out by Caldwell and colleagues can contribute to the understanding of such phenomena.

The Limitations of the Principle of Limited Possibilities

IN DEFENSE of his view that course of cultural evolution is fundamentally multilinear and that it operates in a fortuitous, not in a predictable or predetermined manner, Murdock (1959:131) is obliged to consider contradictory evidence furnished by his own work on kinship. Murdock insists that there only five major types of kinship organization. That only five major kinship systems emerge from a study of a representative sample of 447 societies, drawn from all parts of world and from all levels of culture, suggests existence of extraordinarily powerful selective, deterministic, and anti-chance forces. We urged to believe, however, that this is a superficial interpretation. The resemblances, Murdock insists, are typological, not historical or necessarily even functional (1959:135). They indicate, not operation of natural law in history, but rather inherent limitation in practical possibilities (1959:134). Murdock goes on to explain further that resemblances ... occur because only a certain limited number of combinations of rules of descent, residence patterns, forms of family organization, and methods of classifying kinsmen constitute configurations whose elements genuinely consistent with each other, so that they represent states of equilibrium toward which other combinations tend to gravitate over time (1959:135). Were it not for stipulation contained in immediately preceding sentence that consistency and equilibrium in question not necessarily functional, but may be merely typological, these remarks would serve as a deterministic approach to explanation of parallel and convergent cultural evolution. It is clear that Murdock is making an energetic attempt to have his cake and eat it. Or worse, that mere euphemism here plays role of counter-hypothesis. This gambit is falsely dignified by name the principle of limited possibilities.