John Edward Terrell
Please note: this commentary, recovered on 15-Jan-2017, was originally published in Science Dialogues on 12-Feb-2015.
Abstract – Human biogeography is not a thriving scientific enterprise. Why? In part because our species is remarkably talented at niche construction and highly inventive at adapting our socially learned ways of making a living and staying alive to meet the challenges and opportunities around us wherever we find ourselves on the planet. Nonetheless there is political as well as scientific need in the 21st century for an inclusive biogeographical perspective on human diversity recognizing that we are a globally distributed species whose diversity is framed by isolation-by-distance constrained by our social, economic, and political networks, and whose impact on the environment and our own sustainability is substantial and critically in need of informed restructuring.
This is part 3 of a 3 part series at SCIENCE DIALOGUES
POSSIBLY THE FIRST ATTEMPT IN RECENT YEARS to put humans on the agenda of biogeography was in 1974 at a small invitational conference in Washington, D.C. with this goal supported by the Wenner-Gren Foundation for Anthropological Research and organized by William Fitzhugh at the Smithsonian Institution and John Terrell at Field Museum of Natural History in Chicago (Kolata 1974). Human biogeography was provisionally defined by the organizers as “the study of the size, distribution, and population structure of, and the interactions among, human populations found in similar or divergent habitats, and of the conditions and events leading to the development and maintenance of similarities and differences among human populations living at various points on the earth’s surface” (Terrell 1977c: 5).
In 2012 the University of California Press published the first modern textbook in English on how and why we are distributed as we are globally, Alexander Harcourt’s Human biogeography (2012). As one reviewer noted about this book: “to study such patterns effectively one must not only work with an immense body of data, but also effectively employ theories and methods from both anthropology and biogeography” (Banks 2013: 39). Further, much of human diversity, as Harcourt emphasizes, is not about genes determining human behavior or even influencing what we do, but rather about our socially mediated interactions with the world (Hart 2012: 330).
Units of analysis
The biologist Richard Levins, one of the attendees at the Washington conference in 1974, pointed out that comparing the geographical distribution, variation, and demographic characteristics of human beings with these dimensions in other species is problematic. Biogeographers commonly then and now use taxonomic species as their units of analysis since (by definition, at least) species cannot interbreed. But what characteristics should be used to delimit appropriate human units for comparison given that all of us can at least potentially interbreed even if circumstance, preference, or spatial remove may keep Homo sapiens from being a panmictic species (Caspari 2003)?
When the science writer Gina Kolata reported in Science in 1974 on this conference, she noted that selecting the appropriate human units might be contingent on the research question being asked. If so, then defining the units might be done, for instance, by parsing linguistic, genetic, or cultural traits as the salient diagnostic characters (Kolata 1974). However, the crux of the issue raised by Levins and others at the conference remains. When it comes to variation within our species are the units however defined biologically meaningful? For example, are human groups defined linguistically (i.e., as ethnolinguistic populations) also biologically discernible, informative, and more than ephemeral (Kelly 2002)?
The answer is probably negative. The partitioning of people by language, for instance, is perhaps more extreme in the New Guinea region of the southwestern Pacific than anywhere else on earth. Although it has long been conventional to say that linguistic differences can be used to map biologically persistent populations, research on both cultural and genetic similarities and differences among communities in this part of the world has shown that their diversity when mapped geographically is structured most clearly not by language but rather by isolation-by-distance constrained by social networks and local environmental conditions such as ground slope and topographic ruggedness (Terrell 2010a, 2010b).
Systematic human biogeography
Although, as Barth remarked, it has long been conventional to talk about diversity within our species by presupposing there are discrete aggregations of people on earth that can be labeled as human populations, ethnic groups, and the like, it is probable that many of those attending the 1974 conference were fully aware of the challenges of defining units of analysis in the human sciences. They were not merely trying to map these sciences into the research agenda of species biogeography as then understood and practiced in the biological sciences. Yet it is also true, as John Terrell noted in the introduction to the resulting conference volume, that our human environment is not just a social construct: “People are [also] elements in a far more complex system, at best only partly of man’s design . . . within which a change in anyone element or relationship is likely to effect changes, of a greater or lesser degree, in all the others” (Terrell 1977a: 245).
Although the phrase has won few converts, Terrell suggested at the conference that such networks of interactions might be called geographic systems:
a geographic system is the interactive configuration among the size, distribution and interaction structure of a set of local populations and the elements and interaction structure of the area of their occurrence, analysed as a complex of intercommunicating variables within which a change in any one variable or relationship is likely to effect changes, of a greater or lesser degree, in all the others. (Terrell 1977b: 65)
Key here is the qualification “a greater or lesser degree.” As Herbert Simon once remarked: “To a Platonic mind, everything in the world is connected with everything else—and perhaps it is. Everything is connected, but some things are more connected than others” (Simon 1973: 23). What Simon had in mind were complex hierarchical systems: a broad class (physical, chemical, biological, social, or artificial) exhibiting what he termed “loose horizontal coupling” permitting “each subassembly to operate dynamically in independence of the detail of the others; only the inputs it requires and the outputs it produces are relevant for the larger aspects of system behavior” (1973: 16).
Networks human biogeography
Folk human biogeography presupposes that groups of some kind exist (perhaps simply because people say they exist), and similarities among such corporate players on the world stage of history can be attributed to common ancestry, adaptive convergence, or diffusion (which in the biological sciences is often called admixture) across the boundaries that supposedly exist between such corporate entities (Bashkow 2004). Systematic human biogeography interpreted the way Simon has described complex systems similarly also would appear to take for granted the presence of subsystems needing to communicate with one another but only in so far as inputs and outputs are relevant to the behavior and survival of the system as a whole. Yet harkening back to Levins’ concern in 1974: how should we define boundaries and systems in human biogeography?
Although not given much attention at the conference in 1974, an alternative strategy using graph theory was showcased during one of the presentations then (Terrell 1977c), and it is now widely recognized that Simon’s way of thinking about systemic relationships is not the only way to think about the dynamics of loosely-coupled systems. In 1973, for example, Mark Granovetter (1973) used graph theory—now more generally known as network analysis—to examine how the strength of our ties with others can determine our social mobility, the diffusion of ideas, the political and economic organization of society, and on a more general level, the cohesion of society writ large.
Network analysis enables us see the world around us as one of connections that shape observed phenomena, rather than as one where the intrinsic properties of predefined entities—groups, populations, tribes, systems, and the like—determine the behavior and outcomes of human interactions. Today network analysis in biogeography holds promise, but is still far from conventional (e.g., Kivelä et al. 2015; Radil et al. 2010; Terrell 2010b).
As Shakespeare asked, what’s in a name? It could be argued that anthropology, ethnology, or Erdkunde in the 19th century was simply another name for what would now be called biogeography focused narrowly on one species, namely us (Terrell 2006). This synonymy would be harder to assert for anthropology, human geography, and biogeography in the 20th century in part because the renowned anthropologist Franz Boas and his many prominent students in North America were generally successful at least within the academy at promoting the view that culture (i.e., social learning) is the cardinal trait uniquely defining us as a species (Lewis 2008)—although this historical claim can be contested (Koelsch 2003; Verdon 2006, 2007). What about the 21st century? Is there gain or advantage to be had today by still seeking to unite at least some of the elements of these realms of study under the neglected heading human biogeography?
There is at least one practical reason to do so. While it might seem contentious, it could be said that science as a human activity is more tribal than our species itself. From a social scientist’s point of view—given that we do not naturally come in kinds—it seems astonishing that some geneticists today, for instance, would accept the old folk belief that human groups—geneticists call them populations—are so biologically isolated, and interactions, biological or otherwise, among people living in different places on earth are so rare, that it is proper to assume our biological similarities from place to place must be due to “sudden or gradual transfers of genetic material, creating admixed populations” (Hellenthal et al. 2014: 747; also Elhaik et al. 2014). Perhaps if there were a discipline called human biogeography, it would be more difficult for biologists to overlook what social scientists can tell them about our species, and vice versa.
I thank Eric Clark, Mark Golitko, John Hart, and Kevin Kelly for comments on the working draft.
References § = suggested further reading
Banks, W. E. (2013). Review of Harcourt, Human biogeography. Quarterly Review of Biology 88, 39–40.
Barth, F. (1969). Introduction. In Barth, F. (ed.) Ethnic groups and boundaries: The social organization of culture difference, pp 9–38. Boston, MA: Little, Brown and Company.
Bashkow, I. (2004). A neo-Boasian conception of cultural boundaries. American Anthropologist 106, 443–458.
Caspari, R. (2003). From types to populations: A century of race, physical anthropology, and the American Anthropological Association. American Anthropologist 105, 65–76.
Castree, N. (2009). Charles Darwin and the geographers. Environment and Planning A 41, 2293–2298. §
Cox, C. B. and Moore, P. D. (2010). Biogeography: An ecological and evolutionary approach. 8th ed. Hoboken, NJ: John Wiley & Sons.
Elhaik, E., Tatarinova, T., Chebotarev, D. et al. (2014). Geographic population structure analysis of worldwide human populations infers their biogeographical origins. Nature Communications DOI: 10.1038/ncomms4513.
Fuentes, A., Marks, J., Ingold, T. et al. (2010). On nature and the human. American Anthropologist 112, 512–521.
Granovetter, M. S. (1973). The strength of weak ties. American Journal of Sociology 78, 1360–1380. §
Harcourt, A. H. (2012). Human biogeography. Berkeley: University of California Press. §
Hart, J. P. (2012). Why we are what and where we are. Science 338, 330.
Hellenthal, G., Busby, G. B. J., Band, G. et al. (2014). A genetic atlas of human admixture history. Science 343, 747–751.
Kelly, K. M. (2002). Population. In Hart, J. P. & Terrell, J. E. (eds.) Darwin and archaeology: A handbook of key concepts, pp 243–256. Westport, Ct: Bergin & Garvey. §
Kivelä, M., Arnaud-Haond, S. and Saramäki, J. (2015). EDENetworks: A user-friendly software to build and analyse networks in biogeography, ecology and population genetics. Molecular Ecology Resources 15, 117–122.
Koelsch, W. A. (2004). Franz Boas, geographer, and the problem of disciplinary identity. Journal of the History of the Behavioral Sciences 40, 1–22.
Kolata, G. B. (1974). Human biogeography: Similarities between man and beast. Science 185, 134–135.
Laland, K. N. and O’Brien, M. J. (2011). Cultural niche construction: An introduction. Biological Theory 6, 191–202.
Lao, O., Lu, T. T., Nothnagel, M. et al. (2008). Correlation between genetic and geographic structure in Europe. Current Biology 18, 1241–1248.
Lesser, A. (1961). Social fields and the evolution of society. Southwestern Journal of Anthropology 17, 40-48. §
Lewis, H. S. (2008). Franz Boas: Boon or bane? Reviews in Anthropology 37, 169–200.
Odling-Smee, F. J., Laland, K. N. and Feldman, M. W. (2003). Niche construction. Princeton: Princeton University Press.
Radil, S. M., Flint, C. and Tita, G. E. (2010). Spatializing social networks: Using social network analysis to investigate geographies of gang rivalry, territoriality, and violence in Los Angeles. Annals of the Association of American Geographers 100, 307–326. §
Simon, H. A. (1973). The organization of complex systems. In Pattee, H. H. (ed.) Hierarchy theory: The challenge of complex systems, pp 1–27. New York: George Braziller.
Stocking, G. W., Jr (1987). Victorian anthropology. New York: Free Press.
Terrell, J. E. (1977a). Biology, biogeography and man. World Archaeology 8, 237–248.
Terrell, J. E. (1977b). Geographic systems and human diversity in the North Solomons. World Archaeology 9, 62–81.
Terrell, J. E. (1977c). Human biogeography in the Solomon Islands. Fieldiana: Anthropology 68, 1–47.
Terrell J. E. (2006). Human biogeography: Evidence of our place in nature. Journal of Biogeography 33, 2088–2098. §
Terrell, J. E. (2010a). Language and material culture on the Sepik coast of Papua New Guinea: Using social network analysis to simulate, graph, identify, and analyze social and cultural boundaries between communities. Journal of Island and Coastal Archaeology 5, 3–32.
Terrell, J. E. (2010b). Social network analysis of the genetic structure of Pacific Islanders. Annals of Human Genetics 74, 211–232. §
Terrell, J. E. (2014). A talent for friendship: Rediscovery of a remarkable trait. Oxford: Oxford University Press. §
Verdon, M. (2006). The world upside down: Boas, history, evolutionism, and science. History and Anthropology 17, 171–187.
Verdon, M. (2007). Franz Boas: Cultural history for the present, or obsolete natural history? Journal of the Royal Anthropological Institute (N.S.) 13, 433–451.
Vincent, J. (2009). Ahead of his time? Production and reception in the work of Alexander Lesser. American Ethnologist 15, 743–751.
Wade, N. (2014). A troublesome inheritance: Genes, race and human history. New York: Penguin Press.
Watson, J. B. (1990). Other people do other things: Lamarckian identities in Kainantu subdistrict, Papua New Guinea. In Linnekin, J. & Poyer, L. (eds.) Cultural identity and ethnicity in the Pacific, pp 17–41. Honolulu: University of Hawai‘i Press.
Wilson, E. O. (1978). On human nature. Cambridge, MA: Harvard University Press.
Wilson, E. O. (2012). The social conquest of the earth. New York: Liveright (a division of W. W. Norton).
© 2015 John Edward Terrell. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author(s) and source are credited. The statements and opinions expressed are those of the author(s) and do not constitute official statements or positions of the Editors and others associated with SCIENCE DIALOGUES.