I decided to focus this blog on these three articles because of the problems they raise in my own data. Here I hope to dive a little deeper into these issues so that I may gain a bit more perspective on the limitations of my results. Although these authors focus their studies on methodological constraints in isotopic research, my goal is to remove the excess soft tissues and pinpoint the main purpose of their study, what would otherwise be considered the bare bones of their intent. I would like to take this blog opportunity to address these issues now, since I will be confronting the following problems in my final article at the end of this class.

Daux V, Lécuyer C, Héran MA, Amiot R, Simon L, Fourel F, Martineau F, Lynnerup N, Reychler H, and Escarguel G. 2008. Oxygen Isotope Fractionation Between Human Phosphate and Water Revisited. Journal of Human Evolution 55: 1138-1147.

Part 1:

The oxygen isotope composition of bones and teeth are used to identify regional origins, long-term residency, and migration of historic and prehistoric human populations. Since the oxygen isotope composition of teeth fix following enamel mineralization, the signatures locked in teeth provide evidence regarding the water source consumed as children. Bone tissue offers a different perspective because the signatures preserved in bone apatite-carbonate reflect the average oxygen isotope composition of the water source consumed before death. This provides information pertaining to long-term residency into (hopefully) late adulthood.

Since many palaeo-climate and environmental scientist rely on these data to reconstruct prehistoric temperatures (the same is true for deep ice-core oxygen signatures), statistical regressions that replicate valid relationships are key. There exists a deep relationship here between the isotope geochemists involved in palaeo-climate reconstruction and the physical anthropologists that use these regression formulae to provenance origin and/or track human migration. For this reason, Daux et al. (2008) regenerate the slope and intersection results via regression formulae first articulated by Luz and colleagues, Levinson, and Longinelli and colleagues. The regression formulae from these authors have been extensively used to provide information concerning both historic and prehistoric human mobility. Daux et al. (2008) call into question these parameters due to several factors by highlighting their small sample sizes and temporal contexts. With the oxygen isotope data generated by their sample, Daux et al. (2008) refine these earlier attempts by lumping all four samples together, then regressing the results. The result of this ‘super’ sample provided an equation that fit with the geographic variation of mean meteoric isotope values from various water-catchment facilities across the planet. This also means that the Daux et al. (2008) formula more accurately predicts the oxygen isotope ratios (¹⁸O/¹⁶O) of animal tissues via the natural parameters of the heavy oxygen (¹⁸O) composition of precipitation across the globe (i.e. temperature, distance from the coast, and altitude). One more important dimension to mention from this study is the results obtained from cooking certain types of food. Here the authors test whether boiling or heat-drying meat and grain affected the isotope composition of specific foods. The result of this pilot study showed that as light oxygen (¹⁶O) evaporated first, the food quickly reached isotopic equilibrium with the more enriched surrounding water, elevating the oxygen isotope signature of the food by almost +2 per mil.

The reason for this long rant is because my oxygen results, obtained from early 19^th century soldiers, is likely affected by this cooking enrichment effect. It is however unknown to what extent body water is composed of water ingested from food (some estimates place this value between 10% and 30%). Bearing this in mind I will have to look a little more carefully at my tooth and bone oxygen results. Sorry, but I had to get this all out. My next two article summaries are much shorter, I promise.

Part 2:

Apart from being comprehensive and humble about their successful contribution(s), Daux et al. (2008) gently disintegrate one layer of canonical incumbency at a time. It is an interesting read precisely because the authors knew the scale and scope of their work. They removed what had previously held sway over the scientific community for almost 20 years. They understood the scope of this impact, too, singling out archaeologists interested in these issues, advocating more caution when undertaking this kind of research.

What interests me the most however are the oxygen isotope results obtained from cooking and heat-drying food. This has great potential in explaining why some of my oxygen isotope results (a significant fraction of them, in fact) were so ¹⁸O heavy. Heavy oxygen values suggest residency or origins at lower levels of latitude. In the United States, this means anywhere from the Carolinas to the Florida panhandle. However, Daux et al.’s (2008) study points out that this could be wrong. Instead, it is possible that some of these individuals lived at more northerly latitudes yet consumed significant quantities of stew, soups, and other cooked foods. And they did. This study is of major cross-disciplinary importance, and it is nice to see that from time to time one article can make such a drastic impact. The authors knew it; now everybody knows it – back to the drawing board on this issue.

Bataille CP and Bowen GJ. 2012. Mapping ⁸⁷Sr/⁸⁶Sr Variations in Bedrock and Water for Large Scale Provenance Studies. Chemical Geology 304-305: 39-52.

Part 1:

Strontium is incorporated into plants from the regional bedrock, which is then passed on unaltered to consumers. Since internal mass fractionation factors that affect the ⁸⁷Sr result in tooth enamel are corrected by the mass spectrometer itself, strontium isotopes can determine the location of the foods consumed during childhood. Although similar to oxygen isotopes in application, strontium can also be used as a dietary indicator provided that the local (or baseline) strontium variation in animal tissues is known. Until recently there has been no attempt to document the ⁸⁷Sr composition of the United States and Canada.

Lucky for me, however, Bataille and Bowen (2012) released this research right around the time I received my enamel strontium results (in April). Unfortunately, though, their study terminates at the Canada-U.S. border. There is nothing particularly spectacular about this study (other than the fact that I and others desperately needed it), being a rudimentary data driven study to produce variation maps for forensic and archaeological purposes. The authors use both lithic-specific and water-catchment parameters (and samples) to generate their maps, two important variables covering both the strontium composition of plants (lithic-specific) and water (water-catchment). In this respect, their contribution is another attempt to determine the baseline variation of this isotope across the coterminous North American continent. I have included this article in my blog because there is one fairly large problem in using the two variables mentioned above. I will elaborate on this below.

Part 2:

I suspect Bataille and Bowen (2012: 40) knew exactly what they were saying when they noted that: “Bedrock weathering is the main source of Sr to biological systems, however, these authors proposed that with improved understanding the model patterns could be used to interpret the geographic origin of biological materials.” They fall short of telling what might have otherwise been misinterpreted as a perfect relationship between outcrop weathering processes and the soils generated to produce fertile land. They also fail to mention anything about glacial processes forming many of the moraine-dominated landscapes we see today, especially along the northern border of the United States. In relation to my study then, water-catchment data may indeed be erroneous since the major source of Sr in river and lake systems derive from elevated regions, in this case the Appalachian mountain range. The Appalachian mountain range is quite old, forming during the early Paleozoic. This means that farmers growing crop on adjacent valley regions will likely yield biologically derived Sr consistent with those values found in the Appalachian Formation itself. It is here that I think the authors failed to address any of the major, well-known geological processes, substituting their water-catchment data (which is transported Sr) and lithic-time specific models instead (which is the actual geological substrate of the farm land, not the lithic age of the Appalachian mountains). In my opinion, the authors knew that generating these maps would be problematic. I am not saying that it is not a good study, it is. However it seems apparent to me that Bataille and Bowen (2012) deliberately chose not to include soil formation processes here. In the end, it is more likely that they were uncomfortable with the uncertainty that random processes would have on their mathematical models.

Hedges REM. 2003. On Bone Collagen – Apatite – Carbonate Isotopic Relationships. International Journal of Osteoarchaeology 13: 66-79.

Part 1:

A systematic relationship exists between the carbon isotope composition of bone apatite and collagen, frequently denoted in the literature as Δ¹³C_ap-col. This relationship assumes that carbon from different dietary nutrients (protein, lipids, and carbohydrates) are incorporated into the skeleton in linear proportions. The main reason why this constant offset varies among different animal trophic levels is however poorly understood. Lee Thorp and colleagues were the first to discover that the dietary spacing of collagen and mineral apatite varies throughout food web depending on the trophic level of an organism. That is, between carnivores (small offset), omnivores (intermediate offset) and herbivores (large offset). Hedges’ (2003) attempt to question the main physiological and dietary mechanisms influencing these spacing differences calls into focus many unexplored hypotheses that have so far (and still to this day) eluded methodological verification. This is a very complicated topic (much of which I still don’t quite understand) that requires a solid background in physiology, biophysics and chemistry. Nonetheless, Hedges (2003) constructs a computer-generated model integrating many of these physical systems, including many known dietary parameters. His final results indicate that his computer generated model accounts for only half of the variation observed in natural systems. The details of this require a lot of explanation, however it is important to keep in mind that this study is the first theoretical attempt at explaining these patterns. The methodological difficulties in obtaining this type of data (e.g. the relationship between gut methanogenesis, expired CO₂, and carbon isotope mass balance) are not small.

It is also important for me to think critically about this problem because I have calculated the Δ¹³C_ap-col spacing for the Smith’s Knoll soldiers in my study. Overall, the data suggest that these soldiers fall within a ‘herbivorous’ diet, with meat constituting only a small fraction of the total diet (10% to 20%). This fits nicely with other data obtained for 19^th century individuals living in North America, notably the isotopic data generated by Anne Katzenberg.

Part 2:

Hedges’ (2003) main intent here was to focus isotopic anthropologists on outside, cross-disciplinary sources of information. So far, major attempts to solve this question among the anthropological community has relied on minor quantitative research. This usually takes the form of calculating total dietary proportion of one photosynthetic plant type (i.e. C₃) over another (i.e. C₄). Since it is basically impossible to determine the proportional amount of dietary admixture of these two plant types with any certainty, Hedges (2003) breaks away from this traditional approach to come up with his own model. However, unlike Bataille and Bowen’s (2012) omission of important sedimentary variables, Hedges (2003) himself indicates that his model is likely too narrow to account for the stochastic nature of atomic routing in the human body. A humble assertion, no doubt, and an important trait to highlight from his study because I think some authors knowingly craft their results to fit the criteria set by their hypotheses. In this case, then, hypothesis testing should undoubtedly be subject to change. For me, this article is a good example of the aforementioned ‘stray from the pack’ mentality outlined by Luker. As a result, I have no formal criticism of his work. What this article has taught me, though, is that my apatite-collagen results are a product of metabolic and physiological mechanisms that are, for the meantime, poorly understood. For now I plan to use the comparative data to interpret my own results, albeit with caution.

In Histories of Scholars, Ideas, and Disciplines of Biological Anthropology and Archaeology, Armelagos (2011) revives the seminal contributions and foundations of anthropology during the 20^th century. His historical analysis focuses not only on the advances in understanding human biological variation, particularly with respect to racial classification systems, but also the social and political background these early anthropologists found themselves within. I will try not to get too carried away with the details of the article. Armelagos has indeed done a great job recanting anthropological exploration over the past 100 years, especially in physical anthropology and archaeology. Here, I will try and integrate my opinion on how he chose to formulate his essay of ideas vis a vis what I think are key developments in the discipline itself, what might otherwise be considered key elements in the development of the cannons of physical anthropological thought.

No North American historical rumination of anthropology could be complete without the mention of Franz Boas. His then counter-approach to the dominant ideas concerning the taxonomic classification of human races not only made him unpopular with the leading scientists of his time, but politically dissociated from his peers when he was blacklisted from the American Anthropological Association (AAA) and removed from the National Research Council (NRC) committees in 1919. It is from here that Armelagos departs from the racist pits of our discipline at its nascence, but never completely departs from the overall theme. Armelagos extends his historiographic account to include many other influential physical anthropologists that helped shape the field, including Ales Hrdlicka, Earnest Hooton, Lewis Binford, the Leaky family, Gordon Childe, and Clark Spencer-Larsen, and how they too developed their scientific approaches to human biology during their academic zenith.

What I particularly liked about this essay was the way the author successfully weaved several themes into his writing. In my opinion, Armelagos carefully chose biographical particularities about each author that situated their overall theoretical aims – what they hoped to convey from their research – and juxtaposed them against the political climate and major paradigms that existed at that time. And by ‘theme’ I mean the sociological categories derived from metric analysis of the skeleton, namely ‘race’. His fetish with how early anthropologists dealt with these problems seemed to be the cornerstone of his analysis. I found this to be both a strength and weakness to his approach. Approximately one-third of his article is devoted to the establishment of anthropology in North America, which means focusing heavily on Boas, omitting several of his achievements in other fields of inquiry, such as his seminal research into the lives of the Kwakiutl inhabitants of British Columbia. On a positive note, though, his general interest about how successive anthropologists departed from the one-to-one intimacy of Taylor’s civilizational teleology to one’s skin pigmentation showed precisely how social ideology can manipulate hypothesis building in science. His shift from Boas’ attempts to put an end to such scientific heresy during the early 20^th century where then muddled by Ales Hrdlicka’s fence-sitting position regarding the race concept. While some authors describe Hrdlicka as an anthropological hero in many respects, ultimately unscathed by racist ideology, many anthropological historians maintain that Hrdlicka himself advocated in favour of the eugenics movement.

Towards the end of his essay, the author infuses other sub-disciplinary pioneers who shaped the course of the ‘new physical anthropology’, the ‘new archaeology’, and briefly summarizes the way these early practitioners colluded to produce what we now call bioarchaeology. Moving forward in time, away from the episteme of Boasian physical anthropology, and into a cohesive framework that included many contributions from scholars like Brian Fagan, Lewis Binford, and Clark Spencer-Larsen (the latter of the three is considered a bioarchaeologists), Armelagos highlights the integration of North American anthropology (omitting linguistic anthropology and its early practitioners like Edward Sapir, Benjamin Lee Whorf, and Boas incidentally), instead of the four-field disintegration mantra that is the constant source of departmental discomfort today. I too, like Armelagos, believe that the North American tradition is fundamental to our studies, no matter what sub-field we ascribe to.

The distasteful and racially charged origin of anthropology will forever be something all fields share, whether cultural, physical, archaeological or linguistic, a common point of methodological departure that has nonetheless reshaped (and rightly so) our perceptions concerning the very origin of our species. Indeed, it was not until the 1960s that physical anthropologists began thinking about ancestry in terms of geographic origin, a time when the civil rights movement was playing out full-stage in the United States. It should also not be forgotten that many of the physical sciences bare questionable beginnings, whether it be the church who blasphemed Galileo for proving the Copernican theory of heliocentricity, or early physicians disemboweling live subjects; modern scientist would never refute the historical correlation between physics, chemistry and the medical sciences, and this is one of the points I think Armelagos was trying to make. Like the Catholic church granting Galileo pardon centuries after his death (in 1992, by Pope John Paul the 2^nd), it was not until June 15^th, 2005, that the AAA granted pardon and uncensored Boas, almost 86 years after silencing his writings and discrediting his (very few) students for their visionary ideas that would eventually become the philosophical cornerstone of modern anthropology.

By temporally shifting his focus from one anthropological generation to the next, Armelagos constructs a narrative that orients itself towards the future of anthropological discourse. His brash undertones (anyone who has ever read anything by Armelagos can relate) paired with critical commentary and a keen sense of historical understanding leads the reader to ask: “so, what comes next?”

If this is indeed how he envisioned the reader to interpret his analysis, and I suspect he did, then the overall message may have been to convince the reader to question not only the content of anthropological literature but also the social landscape embedded within. Taken together, then, his historiographic analysis of anthropology was only one intended theme, while another may have been (and perhaps even subliminal) a social critique of the power structures that guided early modern anthropology inquiry. He managed to achieve this by first tending to the painfully misguided origins of our discipline, building through a liminal stage of anthropologists willing to change their interpretations of human adaptations on a global scale, ending on that very point of departure that begs us to ask as 21^st century anthropology students: “how much does our current social atmosphere influence our ideas concerning the past, present, and future of human nature?” A very good read. Your thoughts??

Armelagos GJ. 2011. Histories of Scholars, Ideas, and Disciplines of Biological Anthropology and Archaeology. Reviews in Anthropology 40: 107-133.

In case anyone was interested, here is part 1 and 2 of the interview with Clifford Geertz — a good way to spend 2 hours! This interview was conducted about 2 years before he died in 2006, I believe.

Part 1:

Part 2:

My plan is to re-write, or re-work, my thesis into article form. I plan on submitting my proposed article to the AJPA, JAS, or IJO for review, and, hopefully publication thereafter. Since my thesis is already ‘complete’, my task will be to compose my article following the style guide from these three journals. Also, I am currently enrolled in a reading course where my main task is to submit another, more historically oriented article to the Society for Historical Archaeology and CJA. To be quite honest, I have never submitted a piece of written work to any peer-reviewed committee, so this is extremely new to me.

Another expectation I had before beginning this semester was that by working these articles into my course-load I would integrate my writing in such a way to minimize extra-curricular work and maximize article-submission-efficiency (whatever that means!). That was idealistic. Now I am faced with the task of not only deciding which information I should include in my articles, but how to simultaneously conform to what the journal editors want to read. This is indeed going to be much lengthier process than I initially thought. The following is a crude outline of what I expect by producing a manuscript suitable for publication.

My Master’s thesis looked at the diet and regional origins of a small sample of soldiers who died during the Battle of Stoney Creek, using stable isotopes. Save the details of the data, I plan to partition the isotopic results into two data-sets. The dietary data (C and N isotope results) I hope to publish in Historical Archaeology or the CJA. My second expectation, the one I hope to complete during this course, is to include all of my isotopic data into one cohesive paper that describes the possible areas of origin, long-term residency into adulthood, and diet, for better-known international journals. I have broken down my summary loosely into 6 sub-headings. These will likely change since each journal requires a different format for submission.  So far my outline consist of the following:

Introduction

A brief summary of the RGS excavations at Smith’s Knoll, including past dietary analysis of historic remains recovered in Ontario (e.g. Raynor and Kennett’s 2008 isotopic study of the Snake Hill remains, Fort Erie, Ontario; Katzenberg’s 1991 isotopic analysis of the Snake Hill soldiers; Katzenberg’s 2000 study of the Belleville and Prospect Hill sample). It is probably also important to include a few isotopic studies conducted on 19^th century U.K. soldiers as well (e.g. Roberts et al. 2012), in order to juxtapose my results against those measured in the U.K. More general information concerning the conflict itself will include: a brief description of the Battle of Stoney Creek itself; maps showing the location of Smith’s Knoll; a general thesis regarding the main point of my results, that the Smith’s Knoll isotopic values suggest regional meteoric water and dietary variability consistent with both North America and the United Kingdom.

Sample Description

A brief description of the number of samples isotopically measured for my study, including the types of tissues analyzed (i.e. collagen, bone and tooth carbonate, and enamel strontium). Age at death estimates based on the fusion of the femoral epiphyses will also be included in this section.

Stable Isotopes and Reconstructing Diet and Regional Origins

Here I plan to include a small literature review of the key, albeit basic methodological concepts in stable isotopic research. Questions to answer that seem to be common in all publications include: what is an isotope? What are the standards used to quantify isotopic values (VSMOW, VPDB, and AIR)? How/why do C3, C4, and CAM plants differentially discriminate between heavy and light carbon? What is the trophic level effect (TLE) for carbon and nitrogen, and how do nitrogen values differentiate terrestrial and marine-based consumers? How is strontium passed up from the local geological substrate into the food chain, and how are strontium values used in identifying local and non-local individuals at a site? And how do converted oxygen isotope values from bones and teeth relate to meteoric water variation we measure in both North America and the U.K.?

Methods

A full-page summary of sample preparation, including materials, in-solution concentrations used to purify collage and carbonate samples, as well as radiogenic sample preparation materials for strontium analysis. To confirm low diagenetic alteration in the Smith’s Knoll remains I will also include a detailed Table reporting my C/N ratios, carbon and nitrogen atomic concentrations, and % collagen yield, results.

Results

 A detailed description of C, N, O, and Sr values obtained from the Smith’s Knoll collection, including statistical data (mean, SD), and how my data fit/deviate with prior oxygen isotopic analysis conducted on teeth by Lisa Blyth in 2003. I have approximately 4-6 scatter plot graphs and 3 Tables that detail and show the relationships between my data. Apart from some strange correlation between my bone collagen and carbonate results, what is typically known as the apatite-collagen spacing, my depictions generally follow the standard trophic level configuration with respect to carbon and nitrogen cycling through the food chain.

Discussion

My discussion section will include the main points of my results, in addition to the isotopic results generated from prior research into the lifestyles, dietary habits, and regional origins of 19^th century North American inhabitants. I could easily get carried away here, but for now I’ll just say that this chapter of my thesis is probably the longest, so selecting what needs to be included in my first draft is going to be difficult.

Conclusions

My conclusion will recap my results; that a select few soldiers have isotopic values consistent with North American origins, with fewer originating from the U.K., while the majority of my sample consists of soldiers with overlapping isotopic values (i.e. those consuming both wheat and maize).

I plan to follow the deadlines listed in the syllabus. My hope is that the final product, what I will submit as a final term paper in this class, will then also be ready for submission to the various journals listed above. If anyone has any pointers, sees anything wrong/misplaced/or missing from my outline, please feel free to comment. Help needed! This is, after all, my first attempt!