Human Biology of the Amazon

For the first time, the Olympic Games will be held in South America. The 31st Olympiad will take place in Rio de Janeiro 120 years after the first games of the modern era were initiated in Athens, Greece, under the auspices of Baron De Courbertin and the Olympic Committee. In that same year of 1896, Brazil saw the first movie exhibition in Rio de Janeiro, then the country’s capital, a developing town with less than 500,000 inhabitants. Anthropology was a young discipline and there was intense debate in academic circles about race, miscegenation and the future of Brazil and its people (Lotierzo, 2013; Santos, 2012; Seyferth, 1985). Also in that year, the Amazonas Theater was inaugurated, in Manaus, one of the richest cities in the world at that time. Those were the golden times of the Rubber Boom and of intense migration to the Amazon region that would generate land, social and ethnic conflicts which still reverberate today (Bueno, 2012; Filho & Souza, 2009; Torres, 2005).

This special issue of the Annals of Human Biology was developed at the request of the Society for the Study of Human Biology to commemorate the Brazilian Olympic Games and to present some of the most recent human biology research taking place in Amazonia.

Anthropological research and its sub-fields have a long tradition in Brazil and in Amazonia, with its rich cultural and biological diversity of native populations (Hern, 1991; Meggers, 1996; Roquette-Pinto, 1917; Salzano & Freire-Maia, 1967; Santos & Mello e Silva, 2006). Up to the first half of the 20^th century, the debate about race, biology and the development of the Brazilian nation generated numerous studies in the area of physical anthropology, especially those conducted by João Baptista de Lacerda and Edgard Roquette-Pinto at the Museu Nacional, in Rio de Janeiro, and Raimundo Nina Rodrigues, at the School of Medicine, in Bahia (Athias, 2007; Santos, 2012; Schwarcz, 1993; Seyferth, 1985). However, after the 1950s, human biology and physical/biological anthropology studies dwindled considerably until the 1980s, when concerns about poverty and nutrition raised the need to investigate the relationships between socio-environmental conditions and biological factors in the generation of the millions of stunted and under-nourished children, especially in the rural areas of the Northeast and North of Brazil (Giugliano et al., 1981, 1984; Minayo, 1987). In the Amazon, the works of Charles Wagley, Emílio Morán and Darna Dufour helped to bring international attention to the need for broader, ecosystemic, approaches to the understanding of traditional populations’ lives and modes of adaptation (Dufour, 1990, 1992; Morán, 1981, 1990, 1993; Wagley, 1974). In the period between 1989–1992, Walter Neves, then co-ordinating the Human Biology Program at the Museu Paraense Emílio Goeldi, in Belém, conducted a series of research projects with riverine populations of Marajó Island, which were among the first anthropological investigations to analyse a wide range of socio-ecological and biological changes taking place in the Brazilian Amazon using an interdisciplinary approach (Silva, 2014). Neves (1989, 1991) also organised two important events (The international seminar “Biologia e Ecologia Humana na Amazônia: Avaliação a Perspectivas”, Belém, January 1987 and the international workshop “Origens, Adaptações e Diversidade Biológica do Homem Nativo da Amazônia”, Belém, May 1988) which brought together national and international scholars to present their latest findings and propose a research agenda for future investigations in human biology, human ecology and biological anthropology of the region (Silva, 2014). From these roots, a number of research efforts have emerged with a focus on traditional and transitional groups, some of which are presented in this volume.

Investigation in human biology has always been interdisciplinary, encompassing an ample array of topics (Madrigal & González-José, 2016; Muehlenbein, 2010) and we considered this when considering contributions to the volume. The organisers and authors also aimed to illustrate the broad perspective of human biology and the 10 papers cover themes from HIV/AIDS research to global climate change.

The articles include populations from Brazil, Bolivia and Ecuador. They are grouped by general subject such as growth and diet, health and disease and climate change. Some are review papers (Brondízio et al., 2016; Dorea & Marques, 2016; Dufour et al., 2016) while others are research articles (Blackwell et al., 2016; Ferreira et al., 2016; Marques et al., 2016; Silva et al., 2016; Urlacher et al., 2016; Vallinoto et al., 2016; Zhang et al., 2016). The papers present perspectives about ecology, public policy and traditional populations and also discuss theoretical issues such as adaptation, impacts of modernisation/westernisation on vulnerable populations and aspects of life history and health of different groups.

Ferreira et al. (2016) present an analysis of growth curves of Xavante children <10 yrs of age living in central Brazil. They noted that Xavante are one of the larger indigenous groups in Brazil; they have experienced rapid economic and environmental change in recent decades and are now dependent on market resources for dietary and other needs. The growth curves were based on longitudinal data collected in waves between 2009–2011. The authors found a high prevalence of stunting, but a pattern of growth in weight-for-age closer to the WHO reference values, especially for males. Based on their findings, the authors argued that the high prevalence of stunting indicates that the advances in health and well-being obtained for other segments of the Brazilian population have not adequately reached indigenous children.

Zhang et al. (2016) also analysed growth rates of an Amerindian population, in this case the Tsimané who live in a remote area of Bolivia. Specifically, they used longitudinal data collected annually between 2002–2010 to document rates of growth in the height of Tsimane children 2–11 years of age and explore the extent of catch-up growth. They found growth velocities lower than the WHO reference values, which is not unexpected given the high prevalence of stunting in children and low adult stature. Interestingly, they found more rapid growth rates in stunted compared to non-stunted children and evidence of catch-up growth by age 11 years in some children.

Urlacher et al. (2016) addressed the complexities of the relationship between market integration and sub-adult body size and nutritional status among the Shuar. Using a relatively large sample and multiple measures of market integration, this piece builds on previous work and makes clear that the effects of market integration on sub-adult body size and nutrition are heterogeneous—varying by age-class and sex. By using multiple measures of market integration, this work demonstrates that not all changes have equal effects and, thus, argues for the importance of integrating current knowledge and hypotheses in human biology with ethnographic data on the socio-ecological context of the population. Many of the ideas articulated in the discussion have the potential to stimulate new research on this complex and important topic in the Amazon and elsewhere.

The contribution by Dufour et al. (2016) is a comprehensive review of the current state of knowledge of traditional Amazonian foods and diets in which they are incorporated. They argue that, although the general characteristics of Amazonian diets are known, there is a paucity of quantitative data on actual food intake, which limits our ability to link diet with biology and understand the nutrition transitions occurring in the region. They find that their study populations, even though living in highly diverse environments, have a limited repertoire of foods. The diets are very high in carbohydrates, and may not be sufficiently dense in energy and micronutrients during the period of growth and development to meet sub-adult needs.

The paper by Dórea and Marques (2016) provides an overview about environmental mercury in the Amazon and its implications to human health. Looking at previous research conducted on breastfeeding, growth and fish consumption, their conclusion was that MeHg at present does not represent an important threat to most rural populations, even though mercury levels can be high among certain groups.

Marques et al. (2016) addressed an increasingly important global issue—environmental contamination and human health. Specifically, they examined the dilemma of balancing the importance of breastfeeding with exposure to mercury among Amazonian riverine populations. Many Amazonian populations are exposed to a high level of mercury, which bio-accumulates in the aquatic food chain and is transferred to infants through breast milk, as well as the direct ingestion of fish. Results of this work indicate that, despite infants’ high exposure to mercury, they do not appear to suffer developmental delays. Based on their findings, the authors advocate for the importance of prolonged breastfeeding among rural populations, even those that are heavily reliant on fish as a staple source of protein, as well as further work on the topic.

Silva et al. (2016) present measures of adult health and nutritional status for three non-indigenous groups living in the rural Brazilian Amazon. The groups inhabit different Amazonian ecosystems and have different degrees of access to infrastructure, healthcare and government subsidies, but in general share similar socioeconomic conditions. Stature and the prevalence of obesity were lowest in the most geographically isolated group and the prevalence of systemic hypertension highest in the group closest to the major urban centre (Belém) of the region. The authors noted the limited number of studies on these kinds of groups and call for additional research and public health policies to improve their quality-of-life and health.

Blackwell et al. (2016) address the complex issue of how the human immune system responds to rural Amazonian environments. They examined 22 measures of immune function and found that Tsimane’ of all age groups show elevations in most measures of immune function in comparison to reference populations. They attribute the most dramatic of these elevations to the Tsimane’s high level of exposure to extra-cellular parasites. They suggest the Tsimane’ results may be generalisable to other Amazonian populations, given the ubiquity and pervasiveness of parasitic infections.

The research by Vallinoto et al. (2016) investigates the occurrence of HIV-1 infection in four municipalities of the Archipelago of Marajó. Their data comes from urban and rural areas and represent a broad spectrum of people living in the largest fluvial-maritime archipelago in the world. The study finds a low prevalence of HIV-1 in the area, but they call attention to the high levels of poverty and low education among Marajó youth and the need for public health policies to attend to their needs.

In the final article, in the special volume, Brondízio et al. (2016) provide a critical review of our current state of knowledge regarding the effects of climate change on human populations in the Amazon. They find that, despite considerable interest in understanding the drivers and impacts of climate change in the Amazon Basin, little has been done to connect these changes with human biology and health. Furthermore, outside of public health, little has been done to understand the conditions and related health and human biology of urban populations in the region—even though 70% of the region’s population is now living in urban zones. As the authors argue, both of these major gaps in knowledge present opportunities for interdisciplinary research that would benefit from the skills and perspectives of anthropologically trained human biologists.

The volume underscores the importance of the Amazon basin and its ecosystems and social systems to the world and also how little we still know about its geology, ecology and socio-bio-cultural diversity (Adams et al., 2009; Hoorn et al., 2010). Some of the articles demonstrate rapid socio-environmental changes, calling attention to the urgent need for more research. Additionally, this issue revealed a lack of specific training in human biology and biological anthropology in Brazil, something that Luiz de Castro Faria, in the 1950s, already considered to be critical for the development of the discipline in Brazil (Castro Faria, 2000). Even though some departments, especially in the areas of health and genetics, have been providing applied training in aspects of human biology, there is still only one graduate programme in the country, the Programa de Pós-Graduação em Antropologia at the Universidade Federal do Pará (UFPA), offering Masters and PhD studies with a focus in bioanthropology (together with social anthropology and archaeology) (Gaspar Neto, 2012).

Overall, this issue brings together Amazonian researchers and foreign experts using a wide diversity of approaches to the human biology of Amazonian populations. It provides insights for a potential future research agenda (or agendas) for human biology and biological anthropology, with the objective to stimulate fruitful discussion, collaboration and further research interest in the region.

Disclosure statement

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.