Category Archives: METHODOLOGY

Is archaeology a science? 2. “Plug & Play” archaeology

John Edward Terrell


This is part 2 of a 3 part commentary


New and improved archaeology?

In 1962 the archaeologist Lewis R. Binford had an article published in the journal American Antiquity titled “Archaeology as anthropology”  that electrified the field of academic research into things ancient and not so ancient (Binford 1962). Many saw this paper as a call to turn away from just counting potsherds and pretending to write history toward doing real science in the realm of historical studies (Yu et al. 2015).

Nancy Stone and Lew Binford on an Acheulean site at Yediyapur in the Hunsgi Valley, South India, June 1986. Source: http://antiquity.ac.uk/tributes/binford.html

Since those halcyon days of the 1960s and what came to be called “processual archaeology,” professionals and amateurs alike have voiced strong doubts about whether archaeology is a science. Some have more or less utterly rejected Binford’s claim that archaeologists could be or should be scientists—an unwillingness to play along with Binford and those who would follow in his footsteps that, needless to say, plays right into the hands of someone like Congressman Lamar Smith (Jones 2016; Mizoguchi 2015).

Lewis Binford died in 2011. Despite his many naysayers, the archaeologist Mark Leone observed in a memorial appreciation of the man and his work published in the British journal Antiquity that Binford had unquestionably shown the rest of us “his astonishing capacity to connect archaeological things to the questions that mattered.”

Which raises an obvious concern. What kinds of questions might these be?

Ask no small questions

In 2012, a number of archaeologists, mostly Americans, decided they needed to come up with a list of questions for archaeologists to tackle in the years ahead. The resulting compendium, billed as “Grand challenges for archaeology,” was published in 2014 in the Proceedings of the National Academy of Sciences (PNAS) (Kintigh et al. 2014a).

“The challenges had to be, in principle,” they agreed, “susceptible to a solution supported by data.” In all they came up with 25 worthy concerns. Reading through the listing makes it clear they concluded no challenge too big was beyond the scope of archaeology. Borrowing words from their published report:

These challenges focus on understanding the dynamics of cultural processes and the operation of coupled human and natural systems, recognizing that humans—mediated by culture—both affect and are affected by their natural environments. The challenges addressed questions of emergence, complexity, demography, mobility, identity, resilience, and human–environment interactions. There is a notable lack of concern with the earliest, the largest, and the otherwise unique.

What sorts of challenges are among the 25 listed? They are grouped into five separate categories labeled A–D. Here is a selection of five, one drawn from each category. Keep in mind as you read through them that these five are alike said to be within the reasonable pursue of archaeologists working as archaeologists.

A.7:  What is the role of conflict—both internal factional violence and external warfare—in the evolution of complex cultural formations?

B. 4:  How does ideology structure economic, political, and ritual systems?

C.1:  What processes led to, and resulted from, the global dispersal of modern humans?

D.2:  How do people form identities, and what are the aggregate long-term and large-scale effects of these processes?

E.7:  How do humans perceive and react to changes in climate and the natural environment over short- and long-terms?

What seems most astonishing about these five and the remaining 20 others is that none of these identified challenges said to be of global significance is accompanied by clear statements—specific research hypotheses—that might be taken to be unambiguously testable using archaeologically recovered empirical data. Not one. Yet the claim is made, nonetheless, that

the facts of the past provide the evidence that is essential to confront all of these questions. We harbor no illusions about the difficulties of addressing these classes of problems. Rather, we share a conviction that these are the domains in which the most important problems reside.

These scholars note at the end of their PNAS commentary that they have made a longer version of their collective statement available in American Antiquity (Kintigh et al. 2014b). However, whether what they outline there in more detail would satisfy Congressman Smith is questionable. With regard to challenge A.7, for example, they say:

Exploring the dialectical relationship between conflict and complex cultural formations will undoubtedly foster new approaches to the archaeological record. Conflict is notoriously difficult to identify and quantify through archaeological remains. Though some methods have been developed, more systematic and large-scale analyses are certainly necessary before this question can be thoroughly explored. These methods will involve innovations in osteology and molecular anthropology, as well as advances in comparative studies of material culture and technology.

Plug & Play archaeology

You don’t need to be as skeptical nor as dismissive as Lamar Smith to wonder what these experts have in mind to do in the years ahead to give substance to their 25 grand challenges. Being neither clairvoyant nor a mind-reader, the best anyone else can do is suggest what might or might not fit the bill—if not for Lamar Smith, at least for others.

First, therefore, what wouldn’t meet these challenges? There are many possible ways to answer such a provocative  question. Here is one. Archaeologists should avoid doing Plug & Play archaeology (fig. 1). What does my pairing of these two words refer to? Here is an example.

Figure 1. Source: the author

In January 2016 Marta Lahr at Cambridge University and her colleagues made the cover of the prestigious science journal Nature with a detailed report on human remains dating back about 10,000 years to the early Holocene that had been excavated at Nataruk in northern Kenya (Lahr et al. 2016). Some of the skeletons recovered have traumatic lesions suggesting the probable cause of death (see: fig. 1, left). Not surprisingly perhaps, given this seemingly gruesome physical testimony, Lahr and her co-authors inferred that they had in hand evidence of inter-group violence against people who, given the antiquity of the remains, were probably wandering hunter-gatherers rather than settled agriculturalists.

Now if you were Lamar Smith you might be asking yourself right now “So what?” At the close of their Nature report, Lahr and her colleagues acknowledge directly that the apparent violence attested at Nataruk might be an “ephemeral, but perhaps not unusual, event in the life of prehistoric foraging societies.” Before then in their report, however, and certainly in the press coverage around the world that this report quickly received, what is featured are possible stories about interpersonal violence that could be told given such ancient cold-case injuries.

Both in their report in Nature and in subsequent popular accounts, the central claim made is that these scholars have caught humanity red-handed doing something fundamental—and nasty—long ago strongly hinting that violence is, as many still popularly assume, one of the defining characteristics of our species.

Here is where plug & play come into operation. All that it takes to reach this kind of conclusion about ourselves as human beings is evidence such as these fossil bones (fig. 1, left), a few seemingly reasonable assumptions about human nature (fig. 1, center), and before you know it, you have a story to tell (fig. 1, right).

In fairness, it must be said that at the end their report, Lahr and her co-authors do comment that Nataruk may be showing us little more than “a standard antagonistic response to an encounter between two social groups.” But then why write about these bones, and why feature them on the cover of Nature?

There is no disputing taste, and these authors have clearly done a good job of coming up with what might be said about these prehistoric finds. But “plugging” them into an interpretation—into a story—however appealing is not what STEM education is all about, and surely not what someone like Lamar Smith would take to be real science. It may be true, as these authors conclude at the very end of their report in Nature, that “the deaths at Nataruk are testimony to the antiquity of inter-group violence and war.” So what?

But if not Plug & Play archaeology, then what?

Part 3: Problem solving 

References

Binford, Lewis R. 1962. Archaeology as anthropology. American Antiquity 28: 217-225.

Hart, John P., Termeh Shafie, Jennifer Birch, Susan Dermarkar, and Ronald F. Williamson. 2016. Nation building and social signaling in southern Ontario: AD 1350–1650. PloS One 11, no. 5: e0156178.

Jones, Sharyn. 2016. Anthropological archaeology in 2015: Entanglements, reflection, reevaluation, and archaeology beyond disciplinary boundaries. American Anthropologist 118: 301-316.

Kintigh, Keith W., Jeffrey H. Altschul, Mary C. Beaudry, Robert D. Drennan, Ann P. Kinzig, Timothy A. Kohler, W. Fredrick Limp et al. 2014a. Grand challenges for archaeology. Proceedings of the National Academy of Sciences 111: 879-880.

Kintigh, Keith W., Jeffrey H. Altschul, Mary C. Beaudry, Robert D. Drennan, Ann P. Kinzig, Timothy A. Kohler, W. Fredrick Limp, Herbert D. G. Maschner, William K. Michener, Timothy R. Pauketat, Peter Peregrine, Jeremy A. Sabloff, Tony J. Wilkinson, Henry T. Wright, and Melinda A. Zeder. 2014b. Grand challenges for archaeology. American Antiquity 79: 5-24.

Lahr, M. Mirazón, F. Rivera, R. K. Power, A. Mounier, B. Copsey, F. Crivellaro, J. E. Edung et al. 2016. Inter-group violence among early Holocene hunter-gatherers of West Turkana, Kenya. Nature 529: 394-398.

Levins, Richard. 1966. The strategy of model building in population biology. American Scientist 54:421–431.

Levins, Richard. 1993. A response to Orzack and Sober: formal analysis and the fluidity of science. Quarterly Review of Biology 68:547–555.

Mizoguchi, Koji. 2015. A future of archaeology. Antiquity 89: 12-22.

Moore, Carmella C., and A. Kimball Romney. 1994. Material culture, geographic propinquity, and linguistic affiliation on the North coast of New Guinea: A reanalysis of Welsch, Terrell, and Nadolski (1992). American Anthropologist 96: 370-396.

Terrell, John. 1990. Storytelling and prehistory. Archaeological Method and Theory 2: 1-29.

Terrell, John Edward. 2010. 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 & Coastal Archaeology 5: 3-32.

Terrell, John Edward. 2012. Polynesians and the seductive
power of common sense. Cultural Geographies 20: 135–152.

Terrell, John, Hunt, Terry L., and Gosden, Chris. 1997. The dimensions of social life in the Pacific: Human diversity and the myth of the primitive isolate. Current Anthropology 37: 155-195.

Yu, Pei-Lin, Matthew Schmader, and James G. Enloe. 2015. “I’m the oldest new archaeologist in town”: The intellectual evolution of Lewis R. Binford. Journal of Anthropological Archaeology 38: 2-7.

© 2017 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.

Is archaeology a science? 1: The “So what?” question

John Edward Terrell


           Is archaeology more than storytelling with the help of            visual aids and esoteric props?

This is part 1 of a 3 part commentary


The brahmin sport?

Back in the early 1960s when I was an undergraduate, I was asked by a graduate student in my department what I wanted to be when I grew up. That may not have been the phrasing of the question, but that was the spirit of his inquiry. This individual was the self-identified son of an academically famous father. When I told him I wanted to be an archaeologist, his response didn’t surprise me, although I will leave it to you to decide why I wasn’t taken aback by his retort. With an air of seeming good humor, he quipped: “Ah, the brahmin sport.”

I have no idea who were the particular brahmins he had in mind. Perhaps he was thinking of Agatha Christie and Max Mallowan, or maybe Lord Carnarvon of King Tutankhamun fame. In any case, by the 1960s such a quip was off target.

Agatha Christie (2nd from the left), Max Mallowan (center, with cigarette), and others at the ancient Sumerian city of Nippur in southern Iraq. Source: https://www.penn.museum/blog/collection/archival-practice/mystery-in-the-stacks-a-discovery-is-made-in-the-museum-archives/.
A waste of the taxpayer’s money?

The National Science Foundation was established by an Act of Congress in 1950 to “promote the progress of science; to advance the national health, prosperity, and welfare; and to secure the national defense.” All well and good perhaps, but whether social sciences such as anthropology and archaeology should be viewed as rigorous enough in their objectivity, verifiability, and generality to be included under the umbrella of the NSF was a matter of great and continuing contention even before the establishment of this government agency. Nevertheless, by 1958 an office for the social sciences had been established at the NSF despite the fact, as one board member commented in 1958, “we have to face up to the fact that the social sciences—except for a few extremely limited areas—are a source of trouble beyond anything released by Pandora.”

Given the availability of federal funding for research in the social sciences, anthropology and archaeology by the 1960s were no longer beholden to the whims or the fanatical ideas of the rich and socially privileged. Provided, of course, the research proposals getting funded could convince not only peer reviewers in these disciplines, but Congress, too, that the work lucky enough to be funded was worthy of being labeled as “scientific” not just in name but also in deed.

As the saying goes, that was then, this is now. Over the course of the last half century or so has archaeology lived up to the prospect that it is a science? Or have archaeologists been pulling the wool over the eyes of congressmen and everyday civilians alike as often as some critics of archaeology—and anthropology—then and now contend?

Science—The Endless Frontier

Here’s a bit more history to ponder. World War II had brought the federal government into the arena of basic science research as never before in the history of the United States. Interest in Washington in supporting whatever could be done to win the war was clear and pressing.  Ignorance about what the world was like beyond our borders was no longer excusable and could be deadly. Even anthropologists and other scholars of the esoteric who had lived and worked in the Near East, Asia, and the Pacific found themselves being sought out for their advice and guidance in advancing the war effort (Terrell et al. 1997).

In 1945 Vannevar Bush, the engineer who had led the government’s wartime Office of Scientific Research and Development, wrote a report for President Roosevelt outlining the future for science in the nation cleverly titled Science—The Endless Frontier. He argued persuasively that government support for scientific research and education would prove beneficial to both the peacetime economy and national security. Arguing in graphic terms that scientific progress is essential, his report makes the stakes involved as down to earth as anyone can get: “Science, by itself, provides no panacea for individual, social, and economic ills. It can be effective in the national welfare only as a member of a team, whether the conditions be peace or war. But without scientific progress no amount of achievement in other directions can insure our health, prosperity, and security as a nation in the modern world.”

The newly found sense of relevance to solving the world’s problems carried over after the war in many of the academic disciplines that had hitherto defined themselves as being more about history and diversity than about pattern and process.  Notably geography, ecology, and natural history all experienced what soon came to be called the “quantitative revolution” marked by deliberate and carefully mastered efforts to make such previously descriptive studies more mathematical, more generalizing, and hence more “scientific.” And as I have already noted, eventually even the social sciences were able to convince federal decision makers that these so-called soft sciences were worthy of financial support.

But to repeat: that was then, this is now. And despite claims to the contrary, history can repeat itself.

The “So what?” question and STEM education

Lamar Smith, a Republican, has represented the 21st congressional district in Texas since 1987. He currently serves as the Chair of the House Committee on Science, Space, and Technology which has jurisdiction over programs at NASA, the Department of Energy, the Environmental Protection Agency, the National Science Foundation, the Federal Aviation Administration, and the National Institute of Standards and Technology. He supports Donald Drumpf on border security, not using federal tax dollars to fund abortions under the Patient Protection and Affordable Care Act (also known as Obamacare), and reigning in the “costly, overly burdensome regulations” of the Environmental Protection Agency. He is also strongly opposed to wasting taxpayer’s dollars funding frivolous or low-priority projects, particularly in the social sciences. In 2016, for example, Democrats in Congress viewed his actions as Committee Chair as “a political litmus test that would allow Smith and other Republicans to trim research by social scientists and those studying climate change.”

Lamar Smith evidently likes to take the social sciences head on. Currently, however, there are also less direct ways of challenging whether they are wasteful and frivolous. Take STEM, the acronym that stands for Science, Technology, Engineering, and Mathematics educational programs and curricula. In the words of one prominent advocacy group:

The STEM Education Coalition works aggressively to raise awareness in Congress, the Administration, and other organizations about the critical role that STEM education plays in enabling the U.S. to remain the economic and technological leader of the global marketplace of the 21st century. Members of the STEM Coalition believe that our nation must improve the way our students learn science, mathematics, technology and engineering and that the business, education, and STEM communities must work together to achieve this goal.

In November 2016 the Coalition sent a memorandum to President-elect Donald Trump titled “STEM Education, Good Jobs and American Prosperity.” Nowhere in this statement do the words “social science” or “humanities” occur. Furthermore, the memorandum notes, for instance, that the “top 10 bachelor-degree majors with the highest median earnings are all in STEM fields.”

Is archaeology science?
Koster Site, Kampsville, Illinois in the 1970s. Source: http://users.stlcc.edu/mfuller/koster.html

Few would question that archaeology can be fun, fascinating, entertaining, and an entirely worthwhile summer camping experience. How would cable channels such as Discovery and National Geographic keep the viewing audiences they have without the mysteries and thrilling excitement of archaeological discoveries in places near and far?

Source: https://commons.wikimedia.org/wiki/File:Stonehenge_(sun).jpg

Granting archaeology’s genuine entertainment value and emotional appeal may not, however, be good enough to position such work as worthwhile enough to merit taxpayer’s dollars. At least not in the eyes of someone like Lamar Smith.

Therefore, the question cannot be artfully avoided. Is archaeology more than storytelling? Is it also a science? An honest answer would have to be maybe yes, maybe sometimes.


Part 2: Plug & Play archaeology


References

Binford, Lewis R. 1962. Archaeology as anthropology. American  Antiquity 28: 217-225.

Hart, John P., Termeh Shafie, Jennifer Birch, Susan Dermarkar, and Ronald F. Williamson. 2016. Nation building and social signaling in southern Ontario: AD 1350–1650. PloS One 11, no. 5: e0156178.

Jones, Sharyn. 2016. Anthropological archaeology in 2015: Entanglements, reflection, reevaluation, and archaeology beyond disciplinary boundaries. American Anthropologist 118: 301-316.

Kintigh, Keith W., Jeffrey H. Altschul, Mary C. Beaudry, Robert D. Drennan, Ann P. Kinzig, Timothy A. Kohler, W. Fredrick Limp et al. 2014a. Grand challenges for archaeology. Proceedings of the National Academy of Sciences 111: 879-880.

Kintigh, Keith W., Jeffrey H. Altschul, Mary C. Beaudry, Robert D. Drennan, Ann P. Kinzig, Timothy A. Kohler, W. Fredrick Limp, Herbert D. G. Maschner, William K. Michener, Timothy R. Pauketat, Peter Peregrine, Jeremy A. Sabloff, Tony J. Wilkinson, Henry T. Wright, and Melinda A. Zeder. 2014b. Grand challenges for archaeology. American Antiquity 79: 5-24.

Lahr, M. Mirazón, F. Rivera, R. K. Power, A. Mounier, B. Copsey, F. Crivellaro, J. E. Edung et al. 2016. Inter-group violence among early Holocene hunter-gatherers of West Turkana, Kenya. Nature 529: 394-398.

Levins, Richard. 1966. The strategy of model building in population biology. American Scientist 54:421–431.

Levins, Richard. 1993. A response to Orzack and Sober: formal analysis and the fluidity of science. Quarterly Review of Biology 68:547–555.

Mizoguchi, Koji. 2015. A future of archaeology. Antiquity 89: 12-22.

Moore, Carmella C., and A. Kimball Romney. 1994. Material culture, geographic propinquity, and linguistic affiliation on the North coast of New Guinea: A reanalysis of Welsch, Terrell, and Nadolski (1992). American Anthropologist 96: 370-396.

Terrell, John. 1990. Storytelling and prehistory. Archaeological Method and Theory 2: 1-29.

Terrell, John Edward. 2010. 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 & Coastal Archaeology 5: 3-32.

Terrell, John Edward. 2012. Polynesians and the seductive
power of common sense. Cultural Geographies 20: 135–152.

Terrell, John, Hunt, Terry L., and Gosden, Chris. 1997. The dimensions of social life in the Pacific: Human diversity and the myth of the primitive isolate. Current Anthropology 37: 155-195.

Yu, Pei-Lin, Matthew Schmader, and James G. Enloe. 2015. “I’m the oldest new archaeologist in town”: The intellectual evolution of Lewis R. Binford. Journal of Anthropological Archaeology 38: 2-7.

© 2017 John Edward Terrell. This is an open-accessarticle 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.

Reconfiguring biological diversity 2. Coming to grips with diversity

John Edward Terrell


This is part 2 of a two part article

Coming to grips with diversity

Perhaps the greatest stumbling block to deciphering how biological diversity is patterned, or structured, in space and time within any given species is that most existing ways of modeling such diversity presuppose that genes are nested in some fashion within demonstrable and persistent primary units that can be labeled as populations, subpopulations, demes, communities, stocks, races, and like. Yet is this how biological reproduction works? Aren’t genes perfectly capable of “escaping,” so to speak, from such allegedly defining and confining “boxes” through the very acts of reproduction, reassortment, growth, and development?

It could be argued that there is irony in the fact that molecular genetics now has made it possible for scientists to map diversity at the genetic level. Yet many are still given to thinking about diversity as if they were compelled by the old limitations of their laboratory techniques to lump this new fine-grained evidence into inclusive nested sets (e.g., Pritchard et al. 2000; Greenbaum et al. 2016; Skoglund et al. 2016).

Perhaps it is not surprising, therefore, that some have concluded that “the observed pattern of global gene identity variation was produced by a combination of serial population fissions, bottlenecks and long-range migrations associated with the peopling of major geographic regions, and subsequent gene flow between local populations” (Hunley et al. 2009).

All three of these identified processes are plausible reasons for biological diversity in time and space. But aren’t all three of these population-level explanations ignoring individual agency and decision-making? Not to mention love, lust, and human compassion?

Moving beyond population modeling

Current population-level modeling based on molecular genetics is arguably an advance over older metapopulation models framing diversity as an ever-changing flux within species among discrete subpopulations inhabiting separate habitat patches linked by migration and extinction (Fig. 2). Certainly few today would accept that diversity within any species can be adequately explained solely or even largely as the product of fluctuating colonization and extinction events.

Figure 2. A simple metapopulation model at two time periods (A and B) attributing spatial diversity to a shifting dynamic of colonization and extinction events.

Similarly, the concept of the fitness landscape (also known as as an adaptive landscape; see Fig. 3) introduced by the geneticist Sewell Wright in 1932 is another long-debated way of modeling the dynamic interplay—or balance—of a number of plausible determinants of genetic variation in space and time. As Wright explained in 1932:

The most general conclusion is that evolution depends on a certain balance among its factors. There must be gene mutation, but an excessive rate gives an array of freaks, not evolution; there must be selection, but too severe a process destroys the field of variability, and thus the basis for further advance; prevalence of local inbreeding within a species has extremely important evolutionary consequences, but too close inbreeding leads merely to extinction. A certain amount of crossbreeding is favorable but not too much. In this dependence on balance the species is like a living organism. At all levels of organization life depends on the maintenance of a certain balance among its factors. (Wright 1932)

Figure 3. “Field of gene combinations occupied by a population within the general field
of possible combinations. Type of history under specified conditions indicated by relation
to initial field (heavy broken contour) and arrow.” Source: Wright 1932, fig. 4.

A “balance of factors” sounds right and reasonable, but are the ones he mentions the only major factors that must be taken into account? Surely adaptation is not the only driving force of evolution?

Agency and social networks

Consider the observation that human beings are notably variable in stature, weight, and other characteristics of their appearance. Clearly the gene mutations supporting such phenotypic variation have not resulted in what Wright would describe as “an array of freaks.” Evidently such diversity is not selected against—to use Wright’s way of framing the discussion. Why? Because much of the burden of human adaptation does not need to be genetically endowed. Instead, as most social scientists would insist, much of what we do supporting our survival and reproduction is accomplished using socially learned skills rather than by genetically inherited biological means.

Recently Greenbaum and his colleagues observed that the research strategies and tools of modern network analysis are increasingly being used to explore genetics questions in genomics, landscape genetics, migration-selection dynamics, and the study of the genetic structure of species more generally speaking (Greenbaum et al. 2016).

Adopting a networks approach to genetics makes it possible to come to grips not only with the ways in which racism—to return to Roseman’s point raised earlier—has shaped human variation in the past few hundred years, but also how our species’ mobility, adaptive skills, technologies, and social behaviors have been configuring human variation throughout the history of our species.

Figures 4 and 5 illustrate the potential value of using of network analysis in the study of genetic diversity. The first figure is a network mapping of localities reported in a genome scan published in 2008. While the patterning is complex, there is an obvious geographic signal in the genetic linkages shown. Figure 5 resolves the relationships among a smaller subset of the localities that had been sampled, specifically those in the Bismarck Archipelago-North Solomons region of the southwest Pacific.

Figure 4. Spring-embedding network mapping of the localities sampled in a genome scan of autosomal markers (687 microsatellites and 203 insertions/deletions) on 952 individuals from 41 Pacific populations). Mapping derived from the mean STRUCTURE assignment probabilities when K = 10 reported by Friedlaender at al. (2008) color-coded by geographic location. Blue-white = Asia; blue = Taiwan; black = Europe; red = Polynesia; pink = Micronesia; yellow = New Britain; purple = New Guinea; dark green = North Solomons; green = New Ireland; light green = New Hanover; pale green = Mussau. Source: adapted from Terrell 2010b, fig. 3.

 

Figure 5. Nearest-neighbor structuring of interaction among the localities sampled in the Bismarck Archipelago and North Solomons color-coded to show genetic clustering (blue nodes represent locations not represented in the genetic scan). Source: Terrell 2010b, fig. 11.Both network mappings suggest that geography has influenced the structuring of genetic similarities among people living in the sampled localities shown. Yet it also is apparent that the linkages shown may often be closer than geographic distance alone would lead us to expect. Judging by figure 5, the effect of isolation by distance is evidently constrained by social networks (as projected in this figure using nearest-neighbor linkages). Hence while geographic distance may be contributing to the patterning of genetic diversity among people in this part of the world, geography is by no means the whole story.
Conclusions

The network analysis briefly introduced in figures 4 and 5 had two principal aims, one phylogenetic, the other tokogenetic (Terrell 2010b). Do people living today in the Pacific segregate genetically along lines concordant with the reputedly separate (i.e., cladistic) histories of languages spoken there, principally the divide drawn by linguists and others between speakers of Austronesian and non-Austronesian (Papuan) languages (Terrell 2006)? To what extent does the genetic similarity among people living in different residential communities correlate with the nearest-neighbor propinquity of these sampled places?

Neither of these aims presuppose that the research goal is to define genetically discrete human populations (or subpopulations, demes, groups, communities, races, and the like) either a priori or by using, say, individual-based clustering (IBC) methods (e.g., Ball et al. 2010).

These two aims have more in common with those of the emerging field of landscape genetics (Dyer and Nason 2004; Garroway et al. 2008) than with most previous research in population genetics. However, both of these aims focus more directly on the genetic consequences of the behavior of organisms in space and time—in this case, humans—than on the geography, ecology, and environmental history of the locales where the people in question reside.

Both can also be seen as stepping back from Roseman’s observations about the impact of racial politics and social practices on the human genome in the past few centuries to underscore a more general issue in evolutionary biology: How much do the mobility and social behavior of individuals within any given animal species structure the genetic variation of that species?

As Dyer and Nason (2004) have remarked: “The evolution of population genetic structure is a dynamic process influenced by both historical and recurrent evolutionary processes.” Using network theory and visualization techniques to map the genetic structure of a species in space and time is still in its infancy. Reconfiguring how science grapples with the inherent complexity of evolution as an ever unfolding process using network approaches has the promise of making it easier to explore how comparable or dissimilar species are in their strategies for survival and reproduction (Fortuna et al. 2009).

Looking long and hard at what other species do to survive and reproduce may make it easier for us to see just how toxic our own social strategies—and the assumptions supporting them—can be.

Acknowledgements

I thank Neal Matherne and Tom Clark for their comments on a draft of this commentary.

References

Ball, Mark C., Laura Finnegan, Micheline Manseau, and Paul Wilson. 2010. Integrating multiple analytical approaches to spatially delineate and characterize genetic population structure: An application to boreal caribou (Rangifer tarandus caribou) in central Canada. Conservation Genetics 11, 6: 2131-2143.

Dyer, Rodney J., and John D. Nason. 2004. Population graphs: The graph theoretic shape of genetic structure. Molecular ecology 13, 7: 1713-1727.

Fortuna, Miguel A., Rafael G. Albaladejo, Laura Fernández, Abelardo Aparicio, and Jordi Bascompte. 2009. Networks of spatial genetic variation across species. Proceedings of the National Academy of Sciences 106, 45: 19044-19049.

Friedlaender, Jonathan S., Françoise R. Friedlaender, Jason A. Hodgson, Matthew Stoltz, George Koki, Gisele Horvat, Sergey Zhadanov, Theodore G. Schurr, and D. Andrew Merriwether. 2007. Melanesian mtDNA complexityPLoS One 2, 2: e248.

Friedlaender, Jonathan S., Françoise R. Friedlaender, Floyd A. Reed, Kenneth K. Kidd, Judith R. Kidd, Geoffrey K. Chambers, Rodney A. Lea et al. 2008. The genetic structure of Pacific IslandersPLoS Genet 4, 1: e19.

Garroway, Colin J., Jeff Bowman, Denis Carr, and Paul J. Wilson. 2008. Applications of graph theory to landscape genetics. Evolutionary Applications 1, 4: 620-630.

Greenbaum, Gili, Alan R. Templeton, and Shirli Bar-David. 2016. Inference and analysis of population structure using genetic data and network theory. Genetics 202.4: 1299-1312.

Hellenthal, Garrett, George BJ Busby, Gavin Band, James F. Wilson, Cristian Capelli, Daniel Falush, and Simon Myers. 2014. A genetic atlas of human admixture history.” Science 343, 6172: 747-751.

Hunley, Keith, Michael Dunn, Eva Lindström, Ger Reesink, Angela Terrill, Meghan E. Healy, George Koki, Françoise R. Friedlaender, and Jonathan S. Friedlaender. 2008. Genetic and linguistic coevolution in Northern Island MelanesiaPLoS Genet 4, no. 10 (2008): e1000239.

Hunley, Keith L., Meghan E. Healy, and Jeffrey C. Long. 2009. The global pattern of gene identity variation reveals a history of long‐range migrations, bottlenecks, and local mate exchange: Implications for biological race. American Journal of Physical Anthropology 139, 1: 35-46.

Kelly, Kevin 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.

Moore, John H. 1994. Putting anthropology back together again: The ethnogenetic critique of cladistic theory. American Anthropologist (1994): 925-948.

Posada, David, and Keith A. Crandall. 2001. Intraspecific gene genealogies: Trees grafting into networks. Trends in Ecology & Evolution 16, 1: 37-45.

Pritchard, Jonathan K., Matthew Stephens, and Peter Donnelly. 2000. Inference of population structure using multilocus genotype data. Genetics 155, 2: 945-959.

Rieppel, Olivier. 2009. Hennig’s enkaptic system. Cladistics 25, 3: 311-317.

Roseman, Chartes C. 2014. Troublesome Reflection: Racism as the Blind Spot in the Scientific Critique of Race” Human biology 86, 3: 233-240.

Roseman, Charles C. 2014. “Random genetic drift, natural selection, and noise in human cranial evolution. Human Biology 86, 3: 233-240.

Skoglund, Pontus, Cosimo Posth, Kendra Sirak, Matthew Spriggs, Frederique Valentin, Stuart Bedford, Geoffrey R. Clark et al. 2016. Genomic insights into the peopling of the Southwest Pacific. Nature 538: 510-513.

Terrell, John Edward. 2006. Human biogeography: Evidence of our place in nature. Journal of Biogeography 33, 12: 2088-2098.

Terrell, John Edward. 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 & Coastal Archaeology 5, 1: 3-32.

Terrell, John Edward. 2010b. Social network analysis of the genetic structure of Pacific islanders. Annals of human genetics 74, 3: 211-232.

Terrell, John Edward. 2015. A Talent for Friendship: Rediscovery of a Remarkable Trait. Oxford University Press.

Terrell, John Edward, and Pamela J. Stewart. 1996. The paradox of human population genetics at the end of the twentieth century. Reviews in Anthropology 25, 1: 13-33.

Wade, Nicholas. 2014. A Troublesome Inheritance: Genes, Race and Human History. Penguin.

Wilson, David Sloan, and Edward O. Wilson. 2008. Evolution for the Good of the Group”: The process known as group selection was once accepted unthinkingly, then was widely discredited; it’s time for a more discriminating assessment. American Scientist 96, 5: 380-389.

Wright, Sewall. 1932. The roles of mutation, inbreeding, crossbreeding, and selection in evolution. Proceedings of the Sixth International Congress of Genetics , Vol. 1: 356-366.

© 2017 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.

Reconfiguring biological diversity 1. Toxic and obsolete assumptions

John Edward Terrell


This is part 1 of a two part article

IN AN INSIGHTFUL REVIEW of Nicholas Wade’s recent book A Troublesome Inheritance: Genes, Race and Human History (Wade 2014), the anthropological geneticist Charles C. Roseman concluded that current scientific arguments against biological racism are weak and scattered. These failings—my word, not Roseman’s—are far more than just scientifically troubling. “To recuperate a useful scientific critique of race,” he argues, “we need to come to grips with ways in which the political processes of racism have shaped human organisms over the last few hundred years” (Roseman 2014).

As Roseman notes, nobody seriously contests that human variation “is structured in geographic space, through time, and across many social divisions.” What is still up for grabs is how to explain this observable diversity. And as Roseman emphasizes, how we explain human variation cannot ignore the divisive and often destructive power of racism as a potent driver of human evolution. “Without incorporating the effects of racism into models of human variation today, we will not be able to have a cohesive theory of genes and race, and the scientific critique of race will continue to have no teeth.”

While Roseman’s observations focus on human biological diversity, the weaknesses and uncertainties he has highlighted about our explanations for variation within our species apply also to modern science’s grasp of biological diversity more broadly speaking. From this more inclusive point of view, racism is just a particularly invidious human form of social behavior capable of patterning our genetic diversity in time and space. If so, what about other species? How does the patterning of their mobility and social behavior shape their genetic diversity?

“Populations,” “admixture,” and conventional wisdom

Although the human brain can be coaxed into paying close attention to detail and nuance,  as a thinking machine it generally favors expediency and the utility of knowledge over precision and accuracy.  It is not altogether surprising, therefore, that even scientists often still take it for granted that biological species are naturally subdivided into separate “populations” or “subspecies” that  may occasionally—say under changing demographic or environmental conditions—meet and mix, and thereby produce more or less isolated “admixed” new hybrids (e.g., Moore 1994; Hellenthal et al. 2014). The question being overlooked or at any rate downplayed is how real and persistent are these assumed “populations” (Terrell and Stewart 1996; Kelly 2002).

This question may sound academic, but it is not trivial, as Charles Roseman has underscored. When it comes to human beings, the favored word in scholarly circles may be the word population or perhaps deme, group, or community, but for the chap on the street, the more likely choice wouldn’t be one of these formal terms, but rather the more down-to-earth word race. (I still vividly remember being scolded by a famous biological anthropologist decades ago when I was an undergraduate for using this particular “r” word. “We don’t use that word anymore,” he told me. “We use the term stock  instead.”)

What’s at stake here

It has been a foregone assumption in most genetics research for years that different species are by definition and by their biology isolated reproductively from one another, i.e., individuals in different species cannot mate and give birth to viable offspring capable of sustaining life for longer than a single generation. However, even the most committed cladist accepts that biological relationships below the level of the species are tokogenetic, not phylogenetic (Posada and Crandall 2001; Rieppel 2009).

Figure 1. “Tokogeny versus phylogeny. (a) Processes occurring among sexual species (phylogenetic processes) are hierarchical. That is, an ancestral species gives rise to two descendant species. (b) Processes occurring within sexual species (tokogenetic processes) are nonhierarchical. That is, two parentals combine their genes to give rise to the offspring. (c) The split of two species defines a phylogenetic relationship among species (thick lines) but, at the same time, relationships among individuals within the ancestral species (species 1) and within the descendant species (species 2 and 3) are tokogenetic (arrows).” Source: Posada and Crandall 2001, fig. 1.

Here, therefore, is the conundrum. Call them what you want, populations within any given species are not inherently isolated reproductively either by definition and by their biology. Hence to treat populations as natural units, they must first be defined and demonstrated to be isolated and discernible as such in some other way, or ways. Can this be done?

Here is one favored way when the species in question is ourselves. Many people believe that the language you speak is a reliable sign or marker of your true ethnicity and even your race. Is this right?

Hardly. As both fable and risqué jokes alike would have it, any sailor arriving in a strange port of call is likely to discover soon enough that you don’t really need to speak the local language to enjoy a good time while ashore as long as you have a few coins in your pocket. Yet scholars have long written about people living in what some see as the “underdeveloped” regions of the world as being subdivided into recognizable ethnolinguistic groups, language communities, and the like despite the fact that such euphemisms for the old-fashioned word race pigeonhole rather than map the realities of their lives (Terrell 2010a).

But if neither biology nor language inherently—i.e., “naturally”—isolates and thereby subdivides human beings as a species into different populations, subpopulations, demes, communities, stocks, or races, is there anything that does? And what about other species on earth?

Competition and tribalism, or isolation-by-distance?

As Roseman has remarked: “All analyses of human variation make strong assumptions about the mode, tempo, and pattern whenever they interpret statistical results to make evolutionary conclusions” (Roseman 2016). Favored explanations for or against the assumption that our species can be subdivided into enduring natural populations largely fall into one or the other of two basic sorts.

On the one hand, there has long been anecdotal and scholarly evidence, too, that geography and topography can limit how well and how often people are able to stay in touch with one another socially and intellectually as well as sexually. As the authors of one recent study commented, research has shown that there is a strong positive correlation between global genetic diversity within our species and geographic distance. The correlations observed have often been interpreted “as being consistent with a model of isolation by distance in which there are no major geographic discontinuities in the pattern of neutral genetic variation” (Hunley et al. 2009).

As these same authors note, however, discordant gene frequency patterns are also common within our species. It is obvious, too, that physical and social impediments to gene flow have regularly produced both larger discontinuities as well as concordant allele frequency patterns than would be expected based solely on isolation-by-distance (clinal) models of variation (Ibid.).

Adding social impediments to the mix of possible explanations brings into play the second way many have tried to explain why people around the globe appear to be so diverse. While there are many variants of this alternative argument, the essential ingredients are the baseline assumptions that (a) competition between individuals and groups is the main driving force of evolution, (b) human beings are by nature selfish and aggressive creatures, and (c) until recently humans lived in small tribal groups that were not just suspicious of strangers and other communities near and far, but were frequently at war them them, too. All of these claims are not only questionable, but are arguably contrary to the fundamental evolved characteristics of our species (Terrell 2015).


Part 2: Coming to grips with diversity 


References

Ball, Mark C., Laura Finnegan, Micheline Manseau, and Paul Wilson. 2010. Integrating multiple analytical approaches to spatially delineate and characterize genetic population structure: An application to boreal caribou (Rangifer tarandus caribou) in central Canada. Conservation Genetics 11, 6: 2131-2143.

Dyer, Rodney J., and John D. Nason. 2004. Population graphs: The graph theoretic shape of genetic structure. Molecular ecology 13, 7: 1713-1727.

Fortuna, Miguel A., Rafael G. Albaladejo, Laura Fernández, Abelardo Aparicio, and Jordi Bascompte. 2009. Networks of spatial genetic variation across species. Proceedings of the National Academy of Sciences 106, 45: 19044-19049.

Friedlaender, Jonathan S., Françoise R. Friedlaender, Jason A. Hodgson, Matthew Stoltz, George Koki, Gisele Horvat, Sergey Zhadanov, Theodore G. Schurr, and D. Andrew Merriwether. 2007. Melanesian mtDNA complexityPLoS One 2, 2: e248.

Friedlaender, Jonathan S., Françoise R. Friedlaender, Floyd A. Reed, Kenneth K. Kidd, Judith R. Kidd, Geoffrey K. Chambers, Rodney A. Lea et al. 2008. The genetic structure of Pacific IslandersPLoS Genet 4, 1: e19.

Garroway, Colin J., Jeff Bowman, Denis Carr, and Paul J. Wilson. 2008. Applications of graph theory to landscape genetics. Evolutionary Applications 1, 4: 620-630.

Greenbaum, Gili, Alan R. Templeton, and Shirli Bar-David. 2016. Inference and analysis of population structure using genetic data and network theory. Genetics 202.4: 1299-1312.

Hellenthal, Garrett, George BJ Busby, Gavin Band, James F. Wilson, Cristian Capelli, Daniel Falush, and Simon Myers. 2014. A genetic atlas of human admixture history.” Science 343, 6172: 747-751.

Hunley, Keith, Michael Dunn, Eva Lindström, Ger Reesink, Angela Terrill, Meghan E. Healy, George Koki, Françoise R. Friedlaender, and Jonathan S. Friedlaender. 2008. Genetic and linguistic coevolution in Northern Island MelanesiaPLoS Genet 4, no. 10 (2008): e1000239.

Hunley, Keith L., Meghan E. Healy, and Jeffrey C. Long. 2009. The global pattern of gene identity variation reveals a history of long‐range migrations, bottlenecks, and local mate exchange: Implications for biological race. American Journal of Physical Anthropology 139, 1: 35-46.

Kelly, Kevin 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.

Moore, John H. 1994. Putting anthropology back together again: The ethnogenetic critique of cladistic theory. American Anthropologist (1994): 925-948.

Posada, David, and Keith A. Crandall. 2001. Intraspecific gene genealogies: Trees grafting into networks. Trends in Ecology & Evolution 16, 1: 37-45.

Pritchard, Jonathan K., Matthew Stephens, and Peter Donnelly. 2000. Inference of population structure using multilocus genotype data. Genetics 155, 2: 945-959.

Rieppel, Olivier. 2009. Hennig’s enkaptic system. Cladistics 25, 3: 311-317.

Roseman, Chartes C. 2014. Troublesome Reflection: Racism as the Blind Spot in the Scientific Critique of Race” Human biology 86, 3: 233-240.

Roseman, Charles C. 2014. “Random genetic drift, natural selection, and noise in human cranial evolution. Human Biology 86, 3: 233-240.

Skoglund, Pontus, Cosimo Posth, Kendra Sirak, Matthew Spriggs, Frederique Valentin, Stuart Bedford, Geoffrey R. Clark et al. 2016. Genomic insights into the peopling of the Southwest Pacific. Nature 538: 510-513.

Terrell, John Edward. 2006. Human biogeography: Evidence of our place in nature. Journal of Biogeography 33, 12: 2088-2098.

Terrell, John Edward. 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 & Coastal Archaeology 5, 1: 3-32.

Terrell, John Edward. 2010b. Social network analysis of the genetic structure of Pacific islanders. Annals of human genetics 74, 3: 211-232.

Terrell, John Edward. 2015. A Talent for Friendship: Rediscovery of a Remarkable Trait. Oxford University Press.

Terrell, John Edward, and Pamela J. Stewart. 1996. The paradox of human population genetics at the end of the twentieth century. Reviews in Anthropology 25, 1: 13-33.

Wade, Nicholas. 2014. A Troublesome Inheritance: Genes, Race and Human History. Penguin.

Wilson, David Sloan, and Edward O. Wilson. 2008. Evolution for the Good of the Group”: The process known as group selection was once accepted unthinkingly, then was widely discredited; it’s time for a more discriminating assessment. American Scientist 96, 5: 380-389.

Wright, Sewall. 1932. The roles of mutation, inbreeding, crossbreeding, and selection in evolution. Proceedings of the Sixth International Congress of Genetics , Vol. 1: 356-366.

© 2017 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.

Statistical probability vs. baseline plausibility

John Edward Terrell


WE ARE LIVING IN INTERESTING TIMES. Pundits are saying many of us in the United States are no longer able to distinguish between fact and fiction. Globally speaking and equally alarming, the world may be returning to the Dark Ages before the Renaissance when faith rather than informed skepticism ruled the day.

Figure 1. Despite evidence to the contrary, some today deny that the earth’s climate has changed radically since the start of the Industrial Revolution. Source: https://commons.wikimedia.org/wiki/File:Evidence_CO2.jpg

Drill down below the level of popular journalism and social media chatter, and you will discover that even scientists today stand accused of undermining popular faith in facts & figures. Christie Aschwanden at FiveThirtyEight is one of many science writers reporting that scientists have apparently been using statistical tests of significance (in particular, p-values)[1] to decide how true their results may be and whether they should write up their findings for publication. Yet, as Aschwanden observes: “The p-value only tells you something about the probability of seeing your results given a particular hypothetical explanation—it cannot tell you the probability that the results are true or whether they’re due to random chance.”

Drill down yet deeper below the level of common everyday understanding and it turns out statisticians, too, are adding to our collective uncertainty about who and what to believe in. Apparently they no longer agree on how to do what they do, statistically speaking.[2] If they aren’t sure, how can mortals like ourselves decide who to believe and what’s what?

What’s to be done?

If it is true that sweet reason is on the wane in the world today, what can be done—borrowing from a recent presidential campaign—to make America think again?

A conventional response would be that we must buckle down and commit ourselves anew to paying proper attention to data—solid, down-to-earth facts & figures. Surely this isn’t such an impossible task? And to help us out, let’s not forget that modern statistical tests of significance—however contested nowadays they may be by professional statisticians—were developed by experts years ago to help us conclude whether we have enough facts on the table to decide what they are showing us. Therefore, shouldn’t combining due diligence for real facts with properly employed statistical testing be sufficient to get us past the current “post-factual” crisis?

Unfortunately such a seemingly self-evident way of confronting today’s reported decline in the quality of human wisdom and collective insight is not only too simple, but also naive. Here’s why.

The mind’s artful creativity

The biologist François Jacob—he shared Nobel Prize in Medicine in 1965 with Jacques Monod and André Lwoff—titled his 1982 book about evolution The Possible & the Actual.[3] This title seems misleading. Jacob is not advocating in the three beautifully written essays in this slim volume for a traditional no-nonsense view of science as the rock-solid quest for the actual—for truth and certainty—although in his preface he does say:

. . . human life always involves a continuous dialogue between the possible and the actual. A subtle mixture of belief, knowledge, and imagination builds before us an ever changing picture of the possible. It is on this image that we mold our desires and fears. It is to this possible that we adjust our behavior and actions. In a way, such human activities as politics, art, and science can be viewed as particular ways of conducting this dialogue between the possible and the actual, each one with its own rules.

Yet Jacob’s message for us is not as elementary as this statement may suggest. As a committed evolutionist, he has in mind a decidedly utilitarian view of this purported dialogue. In his own words:

In lower vertebrates, sensory information is converted into moto-nervous information in a rigid way. Such animals appear to live in a world of global stimuli closely linked to processes of appropriate responses, what ethnologists call “innate releasing mechanisms.” In contrast, in birds and even more so in mammals, the enormous amount of information coming from the environment is sorted out by sense organs and processed by the brain, which produces a simplified and useful representation of the external world. The brain functions, not by recording an exact image of the world taken as a metaphysical truth, but by creating its own picture.

From this perspective, therefore, asking how truthfully your brain is taking in the world around you is off the mark. The real issue is how usefully it is doing so. “The external reality, the ‘reality’ of which we all have intuitive knowledge, thus appears as a creation of the nervous system. It is, in a way, a possible world, a model allowing the organism to handle the bulk of incoming information and make it useful for its everyday life.”

The plausible and the possible 

Over the years since the publication of The Possible & the Actual, research in cognitive psychology and neuroscience has done much to clarify how—and how selectively—the human mind constructs what Jacob calls the particular “possible world” within which it dwells.[4] Seen from your nervous system’s point of view, the job we are doing when we are dealing with the world isn’t drawing the line, so to speak, between what Jacob called the possible and the actual, but rather between the plausible and the possible —between what our experiences have taught us to expect to find “out there” in the real world and what might possibly be there based instead on logic or fantasy rather than facts & figures (see fig. 2).

Figure 2. From your nervous system’s point of view, the task you are constantly facing when you are dealing with the world around you is where to draw the line between the possible and the plausible, not the possible and the actual.

If so, then as Daniel Kahneman and others have been saying for years, where we draw the line between the plausible and the possible depends not only on facts & figures bolstered perhaps by statistical analyses, but also on our previous experiences, biases, and prior assumptions about the world and how it works that may not only be all but impossible to put on the table but may not even be part of our conscious awareness.[5]

Conclusion

Headlines lamenting that many of us have seemingly lost the ability to distinguish fact from fiction may be catchy and provocative, but we know enough now about how the human mind constructs its sense of reality to conclude—along with Jacob, Kahneman and others—that paying proper attention to facts & figures is only part of the challenge we face nowadays. It can be argued that how science itself, for example, is conventionally done focuses too much on weighing hypotheses in the light of evidence, and not enough on where hypotheses, so to speak, come from in the first place (see fig. 3).

Figure 3. Science is not just an interplay between evidence and hypotheses, but also with the assumptions, beliefs, and prejudices that make some hypotheses seemly more worthy of study and experimentation than others.

The operative question we need to be asking these days, therefore, is not only the statistician’s old “p-value” question “Do I have enough evidence in favor of my hypothesis to reject the null hypothesis?” We must be attending also more than currently seems popular to the broader question “Why do I find my favored hypothesis plausible enough to spend time and money taking it seriously?”

References

[1] Nuzzo, Regina. “Statistical errors.” Nature 506, no. 7487 (2014): 150-152.

[2] Rodgers, Joseph Lee. “Moving in Parallel toward a Modern Modeling Epistemology: Bayes Factors and Frequentist Modeling Methods.” Multivariate Behavioral Research 51, no. 1 (2016): 30-34.

[3] Jacob, François. The Possible and the Actual. Pantheon, 1982.

[4] Pouget, Alexandre, Jeffrey M. Beck, Wei Ji Ma, and Peter E. Latham. “Probabilistic brains: knowns and unknowns.” Nature neuroscience 16, no. 9 (2013): 1170-1178.

[5] Kahneman, Daniel, and Shane Frederick. “A model of heuristic judgment.” The Cambridge handbook of thinking and reasoning (2005): 267-293.

Ascoli, Giorgio A., Matthew M. Botvinick, Richards J. Heuer, and Rajan Bhattacharyya. “Neurocognitive models of sense-making.” Biologically Inspired Cognitive Architectures 8 (2014): 82-89.


John Edward Terrell is Regenstein Curator of Pacific Anthropology at The Field Museum, Chicago, IL 60605. His latest book A Talent for Friendship: Rediscovery of a Remarkable Trait was published on December 1, 2014 by Oxford University Press. Email address: terrell[at]fieldmuseum.org

© 2017 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.

Logical seduction and historical delusion

John Edward Terrell


Please note: this commentary, recovered on 9-Jan-2017, was originally published in Science Dialogues on 20-Feb-2015.


In his acclaimed novel The Oxford Murders, the Argentinean writer and mathematician Guillermo Martínez engagingly shows how easy it is to hide the truth from others by getting them to think that a series of similar events—in this instance, a series of murders—is happening because, when taken in sequence, they appear to add up to a coded message that we are being taunted to decipher.

Judging by appearances, each murder apparently symbolizes one of the logical steps in a predictable sequence, just as most of us would probably agree that the next logical number in the familiar series 2, 4, 8, and 16 must be the multiple 32.  Perhaps, but as the philosopher Ludwig Wittgenstein famously observed, any finite sequence of numbers can be continued in a variety of different ways, not just in the one way that may seem reasonable (Biletzki and Matar 2006).

For example, the narrator, whose name we are never told, is asked early in this novel if he can figure out what is the next symbol in the odd series reproduced here as Fig. 1a.

Figure 1.
Figure 1. Alternative possible solutions
to Martínez’s cryptic symbol series.

Although Martínez never shows us the solution he has in mind (the narrator merely tells us later on that the answer is the number series 1, 2, 3, 4), we suspect those who find riddles like this one appealing are likely to say the solution shown in Fig. 1b is the right resolve:  an answer derived from the rules of symmetry (Fig. 1c). Yet in keeping with Martínez’s revealing observations about both logic and magic set here and there in this story, what if the proper solution is not so playful?

For example, what if the three symbols already revealed follow instead the alternative rule that one stroke equals 1?  If this were so, then the missing fourth symbol in this cryptic series would not be an “M” with a bar drawn horizontally through it (in keeping with our different rule, this strange symbol could stand instead for the number 5), but disconcertingly could be drawn either as a single stroke (Fig. 1d), or possibly as an inscribed circle, the letter “O,” or a zero (Fig. 1e).

Doubt as to the proper resolve of Martínez’s series of symbols illustrates Wittgenstein’s cryptic and oft-quoted remark:  “This was our paradox:  no course of action could be determined by a rule, because every course of action can be made out to accord with the rule. The answer was:  if everything can be made out to accord with the rule, then it can also be made out to conflict with it. And so there would be neither accord nor conflict” (quoted in:  Biletzki and Matar 2006).

I am not a philosopher, nor a novelist.  It seems to me, however, that Martinez’s tale and Wittgenstein’s remark both tell us something about ourselves, about how we are given to looking for similarities among things and events proving that what we are seeing makes sense not by chance but necessity.  It might even be argued that human beings are strongly predisposed to equate similarity with necessity.

This is why we need statisticians, however much statistics may sometimes seem only a cultivated way of lying for effect.  They keep us from foolishly jumping to the conclusion that similarities in appearance or similarities in effect are necessarily similarities of cause.

And in this regard, we need to remember that when statisticians say that something should be attributed to “chance,” they do not mean “without cause.”  Far from it:  the point they are making is that the cause (or causes) is not necessarily the one we think it is.

Note: These observations were originally published as the introduction in my chapter "Return to the entangled bank: Deciphering the Lapita cultural series" in Sheppard, P. J., Thomas, T., and Summerhayes, G. R., eds., Lapita: Ancestors and Descendants, pages 255-269. Monograph 28. New Zealand Archaeological Association, Auckland, 2009.
Reference

Biletzki, Anat and Matar, Anat, “Ludwig Wittgenstein”, The Stanford Encyclopedia of Philosophy (Spring 2014 Edition), Edward N. Zalta (ed.), URL = <http://plato.stanford.edu/archives/spr2014/entries/wittgenstein/>.


BW-JET

John Edward Terrell is Regenstein Curator of Pacific Anthropology at The Field Museum, Chicago, IL 60605. His latest book A Talent for Friendship: Rediscovery of a Remarkable Trait was published on December 1, 2014 by Oxford University Press. Email address: terrell[at]fieldmuseum.org

© 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.