Shuar Health and Life History Project


The Shuar Health and Life History Project is an interdisciplinary collaborative research effort that involves scientists from a number of universities, Ecuadorian health providers, and Shuar colleagues (including through the Shuar Federation). It is co-directed by Drs. Josh Snodgrass (University of Oregon), Sam Urlacher (Baylor University), Felicia Madimenos (CUNY-Queens College), and Melissa Liebert (Northern Arizona University). The project was launched in 2005 by Dr. Larry Sugiyama (University of Oregon), who remains a senior researcher on the project. The other senior members of the research team are Drs. Dorsa Amir (Boston College), Rick Bribiescas (Yale University), Aaron Blackwell (Washington State University), Tara Cepon-Robins (University of Colorado-Colorado Springs), and Theresa Gildner (Dartmouth). The project has also collaborated extensively with colleagues at other universities, including Drs. Herman Pontzer (Duke University), Lara Dugas (Loyola University), Thom McDade (Northwestern University), and Daniel Sznycer (University of Montreal).

The Shuar Health and Life History project examines the ecology and health of indigenous Shuar, as well as non-indigenous Ecuadorians (Colonos), from the Morona-Santiago region of Ecuador. For more information on the field site, click here. Traditionally forager-horticulturalists, Shuar currently experience a wide range of market integration (
i.e., the suite of social and cultural changes that occur with economic development) across their territory. This provides an important opportunity for addressing how economic, social, and dietary changes associated with market integration affect life history tradeoffs, and how those tradeoffs affect health. It allows examination of particular aspects of market integration, predicted life history changes, and actual behavior and health across a wide range of conditions within the same ethnic group. Simultaneously, comparison of Upano Valley Shuar, who are currently more market integrated, with their Colono neighbors provides an opportunity to examine these same variables among people from a different cultural background living under similar socio-ecological conditions. For more information on Shuar, click here.

Project Goals
The goals of the Shuar Health and Life History Project are threefold:

First, the project is investigating how cultural and economic changes in the region affect Shuar health and well-being. One component of this research focuses on growth and nutritional status in Shuar children. We have compared Shuar children to other populations and examined risk factors for poor growth and development. After over 10 years of intensive research, we have amassed an enormous amount of data on growth and development. These results were first described in Blackwell et al. 2009. We have several more recent publications on Shuar growth, including
a paper in the American Journal of Human Biology that describes Shuar growth references (for height, weight, and BMI; Urlacher et al. 2016), a paper in the American Journal of Physical Anthropology that details the application of knemometry to measure childhood short-term growth (Urlacher et al. 2016), and a paper in Annals of Human Biology that describes the effects of market integration on growth (Urlacher et al. 2016).

Shuar Kids
Shuar kids in an Upano Valley community

Another area of research is skeletal health and risk for osteoporosis. This research, led by Dr. Felicia Madimenos, has examined the reproductive and lifestyle factors that influence bone density. Results of this research are detailed in several papers (Madimenos et al. 2011; Madimenos et al. 2012. Also, check out the
profile on the Scientific American blog, which provides a nice summary of the article and also describes the Shuar project as “well known within anthropology for its rigorous methodology and outreach with local participants. It’s also an interdisciplinary site that seems to be great for tackling both biological and cultural anthropology questions.” Here's the link. More recent papers look at bone density among Colonos (Madimenos et al. 2015) and compare and contrast Shuar with the indigenous Tsimane of Bolivia (Madimenos et al. 2020).

Felicia
                        Madimenos bone scan
Felicia Madimenos using a heel ultrasonometer to measure bone mineral density

We are also examining the effects of social change on other chronic conditions such as cardiovascular disease and diabetes, investigating the role of physical activity, chronic psychosocial stress, and diet in shaping disease patterns among Shuar. An early paper in Annals of Human Biology (Liebert et al. 2013) describes
the effects of market integration (i.e., the suite of social and cultural changes that occur with economic development) on cardiovascular and metabolic diseases, concentrating on how factors like proximity to town and consumption of market foods shape risk markers such as blood pressure, lipids, and glucose. This work provides evidence that market integration among Shuar is not a uniformly negative process but instead produces complex cardiovascular and metabolic health outcomes. 

melissa liebert
                      collecting saliva samples
Melissa Liebert helps a Shuar girl collect a saliva sample for cortisol analysis
 
Second, we are using the branch of evolutionary biology known as life history theory to better understand the tradeoffs between different branches of immune function in Shuar children, and to use this information to elucidate how energy is allocated to competing priorities such as maintenance, growth, reproduction and physical activity. These findings have been detailed in a series of publications by Aaron Blackwell in the American Journal of Human Biology (Blackwell et al. 2010) and PLoS Neglected Tropical Diseases (Blackwell et al. 2011). More recent research, led by Dr. Sam Urlacher, uses cutting edge biomarker methods and knemometry (the accurate and reliable measurement of lower leg length) to assess trade-offs between immune function and short-term linear growth in Shuar kids. That research was published in Proceedings of the National Academy of Sciences (Urlacher et al. 2018).

aaron blackwell
                          skinfold and ajhb cover
Aaron Blackwell measuring body fat on a Shuar boy (left); American Journal of
Human Biology cover from November/December 2010 highlighting our work (right)


sam urlacher knemometer
Sam Urlacher using a portable knemometer to measure the lower leg length of a Shuar girl

Further, the project has investigated the relationship between markers of immune function/inflammation (e.g., immunoglobulin E [IgE] and C-reactive protein [CRP]) and several measures of cardiovascular and metabolic health (e.g., fasting glucose and lipids). This research suggests important tradeoffs between immune responses and different aspects of cardiovascular and metabolic health (Liebert et al. 201
1). The project has collaborated with Dr. Thom McDade and former Northwestern graduate student Paula Tallman on an NSF-funded ecological immunology project that investigated CRP variability within the context of this non-industrialized, high infectious disease environment. The findings were described in an article in the American Journal of Human Biology (McDade et al. 2012), and were the subject of a news piece in Science. These results have important implications for research on inflammation and diseases of aging globally, as well as for scientific understandings of the regulation of inflammation. Drs. Tara Cepon-Robins and Theresa Gildner expanded this research by examining how parasite burden structures life history trade-offs, and how shifting patterns of infectious disease exposure alter risk for allergies and autoimmune diseases. Dr. Cepon-Robins led a recent research effort--published in the Journal of Parasitology--that examines the prevalence and infection intensity of parasitic worms among geographically and economically distinct Shuar communities (Cepon-Robins et al. 2014; ); this research was refined in a recent article in the Journal of Physiological Anthropology (Gildner et al. 2016). Recent research, published in the American Journal of Physical Anthropology, documented levels of intestinal inflammation (using fecal calprotectin) and connected these to measures of soil-transmitted helminth infection (Cepon-Robins et al. 2019).

The Shuar project also features prominently in a recently completed NSF-sponsored project led by Dr. Snodgrass and Dr. Geeta Eick (University of Oregon),
"Building the Methodological Toolkit in Biological Anthropology: Dried Blood Spot Methods Development for Addressing Key Evolutionary and Biocultural Questions" (BCS-1638786), that focused on the development and validation of new dried blood spots assays for use in population-level research. The project also involves Drs. Cepon-Robins, Sugiyama, and Madimenos. The project, which is being conducted in the Global Health Biomarker Laboratory at UO, focuses on the biomarkers TPOAb (a marker of autoimmune thyroid disorders), carboxylated osteocalcin (cOC; a marker of bone formation), tartrate-resistant acid phosphatase 5b (TRACP5b; a marker of bone resorption), and Klotho (a marker of stress-related aging). These techniques can then be used in the Shuar project to test a variety of research questions, including how parasitic worm exposure is related to the risk of autoimmune disease.
 
tara cepon
                      preparing fecal samples
Tara Cepon preparing a fecal sample for analysis of parasitic worms

Finally, the Shuar Health and Life History Project seeks to provide health information to participants and community partners in order to assist in targeting prevention and treatment efforts. Our research is conducted in collaboration with Ecuadorian medical colleagues and the Shuar Federation.

Larry Sugiyama
Project founder and co-director Larry Sugiyama weighing a baby

The project facilitates delivery of health information to participants, the Shuar Federation, and local medical providers in three ways: 1) individual health results are provided and explained to each participant; 2) evidence of pathology is conveyed to local medical workers if the participant desires, and assistance provided with acquisition of treatment if necessary and feasible; and 3) overall research results and interpretation are presented to Ministry of Health colleagues, the Shuar Federation Health directorate, and participant community meetings in order to contribute to public health policy.

Drs. Madimenos and Sugiyama received an Engaged Anthropology Grant from the Wenner-Gren Foundation in 2013 ("Engaging Shuar Communities through Collaborative Health Education: Enhancing Participant Agency in Indigenous Health Research") to work with Shuar communities and conduct a series of workshops, presentations and family days to disseminate information regarding health issues in the community. Check out the write-up of the project on the Wenner-Gren website.

engaged anthropology
A Shuar colleague and local health care provider assisted by community members
present on health and family planning in a rural Shuar community


Importance
The research conducted by the Shuar Health and Life History Project is important because it has expanded the view of the extent of health change with market integration (i.e., beyond a focus on chronic disease to a more holistic one that consider osteoporosis, infectious/parasitic diseases, and autoimmune conditions) and has demonstrated that metabolic and cardiovascular effects of market integration are far more nuanced than recognized by previous studies. It has also helped to elucidate the physiological mechanisms and environmental triggers responsible for life history trade-offs, in part through advancements in human biology methods. And, finally, research topics such as the the evolution and environmental calibration of disgust sensitivity demonstrate the utility of conceptual unity and methodological integration across different branches of human evolutionary research—in this case evolutionary psychology and human biology—to elucidate how environmental differences are processed by psychological adaptations to produce variation in fitness-related outcomes.