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Trumble BC, Schwartz M, Ozga AT, Schwartz GT, Stojanowski CM, Jenkins CL, Kraft TS, Garcia AR, Cummings DK, Hooper PL, Eid Rodriguez D, Buetow K, Beheim B, Irimia A, Thomas GS, Thompson RC, Gatz M, Stieglitz J, Finch CE, Gurven M, Kaplan H. Poor Oral Health Is Associated With Inflammation, Aortic Valve Calcification, and Brain Volume Among Forager-Farmers. J Gerontol A Biol Sci Med Sci 2024; 79:glae013. [PMID: 38291985 PMCID: PMC11044433 DOI: 10.1093/gerona/glae013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Indexed: 02/01/2024] Open
Abstract
Poor oral health is associated with cardiovascular disease and dementia. Potential pathways include sepsis from oral bacteria, systemic inflammation, and nutritional deficiencies. However, in post-industrialized populations, links between oral health and chronic disease may be confounded because the lower socioeconomic exposome (poor diet, pollution, and low physical activity) often entails insufficient dental care. We assessed tooth loss, caries, and damaged teeth, in relation to cardiovascular and brain aging among the Tsimane, a subsistence population living a relatively traditional forager-horticulturalist lifestyle with poor dental health, but minimal cardiovascular disease and dementia. Dental health was assessed by a physician in 739 participants aged 40-92 years with cardiac and brain health measured by chest computed tomography (CT; n = 728) and brain CT (n = 605). A subset of 356 individuals aged 60+ were also assessed for dementia and mild cognitive impairment (n = 33 impaired). Tooth loss was highly prevalent, with 2.2 teeth lost per decade and a 2-fold greater loss in women. The number of teeth with exposed pulp was associated with higher inflammation, as measured by cytokine levels and white blood cell counts, and lower body mass index. Coronary artery calcium and thoracic aortic calcium were not associated with tooth loss or damaged teeth. However, aortic valve calcification and brain tissue loss were higher in those who had more teeth with exposed pulp. Overall, these results suggest that dental health is associated with indicators of chronic diseases in the absence of typical confounds, even in a population with low cardiovascular and dementia risk factors.
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Affiliation(s)
- Benjamin C Trumble
- School of Human Evolution and Social Change, Center for Evolution and Medicine, Institute of Human Origins, Arizona State University, Tempe, Arizona, USA
| | - Matthew Schwartz
- School of Medicine, University of New Mexico, Albuquerque, New Mexico, USA
| | - Andrew T Ozga
- Department of Biological Sciences, Halmos College of Arts and Sciences, Fort Lauderdale, Florida, USA
| | - Gary T Schwartz
- School of Human Evolution and Social Change, Center for Evolution and Medicine, Institute of Human Origins, Arizona State University, Tempe, Arizona, USA
| | - Christopher M Stojanowski
- School of Human Evolution and Social Change, Center for Evolution and Medicine, Institute of Human Origins, Arizona State University, Tempe, Arizona, USA
| | - Carrie L Jenkins
- School of Human Evolution and Social Change, Center for Evolution and Medicine, Institute of Human Origins, Arizona State University, Tempe, Arizona, USA
| | - Thomas S Kraft
- Department of Anthropology, University of Utah, Salt Lake City, Utah, USA
| | - Angela R Garcia
- School of Human Evolution and Social Change, Center for Evolution and Medicine, Institute of Human Origins, Arizona State University, Tempe, Arizona, USA
| | - Daniel K Cummings
- Economic Science Institute, Chapman University, Orange, California, USA
| | - Paul L Hooper
- Economic Science Institute, Chapman University, Orange, California, USA
| | | | - Kenneth Buetow
- School of Human Evolution and Social Change, Center for Evolution and Medicine, Institute of Human Origins, Arizona State University, Tempe, Arizona, USA
| | - Bret Beheim
- Department of Human Behavior, Ecology and Culture, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Andrei Irimia
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, California, USA
| | - Gregory S Thomas
- Heart & Vascular Institute, MemorialCare Health System, Fountain Valley, CA and University of California Irvine, Orange, California, USA
| | - Randall C Thompson
- Department of Cardiology, Saint Luke’s Mid America Heart Institute, Kansas City, Missouri, USA
| | - Margaret Gatz
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, California, USA
| | - Jonathan Stieglitz
- Insititue for Advanced Study, Toulouse School of Economics, Toulouse, France
| | - Caleb E Finch
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, California, USA
| | - Michael Gurven
- Integrative Anthropological Sciences, University of California Santa Barbara, Santa Barbara, California, USA
| | - Hillard Kaplan
- Economic Science Institute, Chapman University, Orange, California, USA
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Dalzero A, Beheim BA, Kaplan H, Stieglitz J, Hooper PL, Ross CT, Gurven M, Lukas D. Cross-cousin marriage among Tsimane forager-horticulturalists during demographic transition and market integration. Evol Hum Sci 2024; 6:e18. [PMID: 38572226 PMCID: PMC10988167 DOI: 10.1017/ehs.2024.11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 02/02/2024] [Accepted: 02/12/2024] [Indexed: 04/05/2024] Open
Abstract
Although still prevalent in many human societies, the practice of cousin marriage has precipitously declined in populations undergoing rapid demographic and socioeconomic change. However, it is still unclear whether changes in the structure of the marriage pool or changes in the fitness-relevant consequences of cousin marriage more strongly influence the frequency of cousin marriage. Here, we use genealogical data collected by the Tsimane Health and Life History Project to show that there is a small but measurable decline in the frequency of first cross-cousin marriage since the mid-twentieth century. Such changes are linked to concomitant changes in the pool of potential spouses in recent decades. We find only very modest differences in fitness-relevant demographic measures between first cousin and non-cousin marriages. These differences have been diminishing as the Tsimane have become more market integrated. The factors that influence preferences for cousin marriage appear to be less prevalent now than in the past, but cultural inertia might slow the pace of change in marriage norms. Overall, our findings suggest that cultural changes in marriage practices reflect underlying societal changes that shape the pool of potential spouses.
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Affiliation(s)
- Arianna Dalzero
- Department of Human Behavior, Ecology and Culture, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Bret A. Beheim
- Department of Human Behavior, Ecology and Culture, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Hillard Kaplan
- Economic Science Institute, Chapman University, Orange, California, USA
| | - Jonathan Stieglitz
- Toulouse School of Economics and Institute for Advanced Study, University of Toulouse 1 Capitole, Toulouse, France
| | - Paul L. Hooper
- Economic Science Institute, Chapman University, Orange, California, USA
- Department of Anthropology, University of New Mexico, Albuquerque, New Mexico, USA
| | - Cody T. Ross
- Department of Human Behavior, Ecology and Culture, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Michael Gurven
- Department of Anthropology, University of California, Santa Barbara, California, USA
| | - Dieter Lukas
- Department of Human Behavior, Ecology and Culture, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
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Stieglitz J, Buoro Y, Beheim B, Trumble BC, Kaplan H, Gurven M. Labour's pain: strenuous subsistence work, mechanical wear-and-tear and musculoskeletal pain in a non-industrialized population. Proc Biol Sci 2023; 290:20222497. [PMID: 37161336 PMCID: PMC10170198 DOI: 10.1098/rspb.2022.2497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Accepted: 04/21/2023] [Indexed: 05/11/2023] Open
Abstract
Musculoskeletal pain is the most debilitating human health condition. Neurophysiological pain mechanisms are highly conserved and promote somatic maintenance and learning to avoid future harm. However, some chronic pain might be more common owing to mismatches between modern lifestyles and traits that originally evolved under distinct premodern conditions. To inform assumptions about factors affecting chronic pain vulnerability prior to industrialization, we assess pain prevalence, perceived causes, and predictors among Tsimane forager-horticulturalists. Habitual subsistence work is the primary reported cause of pain throughout life for both sexes, and pain is more common with age, especially in the back, and for those with more musculoskeletal problems. Sex differences in pain are relatively weak, and we find no association between women's reproductive history and pain, contrary to the hypothesis that reproduction causes women's greater pain susceptibility. Age-standardized current pain prevalence is 1.7-8.2 times higher for Tsimane than other select populations, and Tsimane chronic pain prevalence is within the range of variation observed elsewhere. Chronic low back pain is not a 'mismatch disease' limited to post-industrialized populations. Hominin musculoskeletal changes supporting bipedalism probably imposed health costs, which, after millions of years of evolution, remain an epidemiological burden that may be exacerbated by modern conditions.
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Affiliation(s)
- Jonathan Stieglitz
- Institute for Advanced Study in Toulouse, Université Toulouse 1 Capitole, Toulouse 31080, France
| | - Yoann Buoro
- Department of Anthropology, University of California-Santa Barbara, Santa Barbara, CA 93106, USA
| | - Bret Beheim
- Department of Human Behavior, Ecology and Culture, Max-Planck Institute for Evolutionary Anthropology, Leipzig 04103, Germany
| | - Benjamin C. Trumble
- Center for Evolution and Medicine, Arizona State University, Tempe, AZ 85287, USA
- School of Human Evolution and Social Change, Arizona State University, Tempe, AZ 85287, USA
| | - Hillard Kaplan
- Economic Science Institute, Chapman University, 1 University Drive, Orange, CA 92866, USA
| | - Michael Gurven
- Department of Anthropology, University of California-Santa Barbara, Santa Barbara, CA 93106, USA
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Kaplan H, Hooper PL, Gatz M, Mack WJ, Law EM, Chui HC, Sutherland ML, Sutherland JD, Rowan CJ, Wann LS, Allam AH, Thompson RC, Michalik DE, Lombardi G, Miyamoto MI, Eid Rodriguez D, Copajira Adrian J, Quispe Gutierrez R, Beheim BA, Cummings DK, Seabright E, Alami S, R. Garcia A, Buetow K, Thomas GS, Finch CE, Stieglitz J, Trumble BC, Gurven MD, Irimia A. Brain volume, energy balance, and cardiovascular health in two nonindustrial South American populations. Proc Natl Acad Sci U S A 2023; 120:e2205448120. [PMID: 36940322 PMCID: PMC10068758 DOI: 10.1073/pnas.2205448120] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Accepted: 01/24/2023] [Indexed: 03/22/2023] Open
Abstract
Little is known about brain aging or dementia in nonindustrialized environments that are similar to how humans lived throughout evolutionary history. This paper examines brain volume (BV) in middle and old age among two indigenous South American populations, the Tsimane and Moseten, whose lifestyles and environments diverge from those in high-income nations. With a sample of 1,165 individuals aged 40 to 94, we analyze population differences in cross-sectional rates of decline in BV with age. We also assess the relationships of BV with energy biomarkers and arterial disease and compare them against findings in industrialized contexts. The analyses test three hypotheses derived from an evolutionary model of brain health, which we call the embarrassment of riches (EOR). The model hypothesizes that food energy was positively associated with late life BV in the physically active, food-limited past, but excess body mass and adiposity are now associated with reduced BV in industrialized societies in middle and older ages. We find that the relationship of BV with both non-HDL cholesterol and body mass index is curvilinear, positive from the lowest values to 1.4 to 1.6 SDs above the mean, and negative from that value to the highest values. The more acculturated Moseten exhibit a steeper decrease in BV with age than Tsimane, but still shallower than US and European populations. Lastly, aortic arteriosclerosis is associated with lower BV. Complemented by findings from the United States and Europe, our results are consistent with the EOR model, with implications for interventions to improve brain health.
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Affiliation(s)
- Hillard Kaplan
- Economic Science Institute, Chapman University, Orange, CA82866
| | - Paul L. Hooper
- Economic Science Institute, Chapman University, Orange, CA82866
- Department of Anthropology, University of New Mexico, Albuquerque, NM87131
| | - Margaret Gatz
- Center for Economic and Social Research, University of Southern California, Los Angeles, CA90089
| | - Wendy J. Mack
- Department of Population and Public Health Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA90089
| | - E. Meng Law
- Department of Neurology, Keck School of Medicine, University of Southern California, Los Angeles, CA90089
- Department of Radiology, The Alfred Health Hospital, Melbourne, VIC3004, Australia
- iBRAIN Research Laboratory, Departments of Neuroscience, Computer Systems and Electrical Engineering, Monash University, Melbourne, VIC3800, Australia
| | - Helena C. Chui
- Department of Neurology, Keck School of Medicine, University of Southern California, Los Angeles, CA90089
- Alzheimer’s Disease Research Center, Keck School of Medicine, University of Southern California, Los Angeles, CA90089
| | | | | | - Christopher J. Rowan
- Renown Institute for Heart and Vascular Health, Reno, NV89502
- School of Medicine, University of Nevada, Reno, NV89557
| | - L. Samuel Wann
- Division of Cardiology, University of New Mexico, Albuquerque, NM87131
| | - Adel H. Allam
- Department of Cardiology, School of Medicine, Al-Azhar University, Al Mikhaym Al Daem, Cairo4334003, Egypt
| | - Randall C. Thompson
- Saint Luke’s Mid America Heart Institute, University of Missouri - Kansas City, Kansas City, MO64111
| | - David E. Michalik
- Department of Pediatrics, School of Medicine, University of California at Irvine, Orange, CA92617
- MemorialCare Miller Children’s and Women’s Hospital, Long Beach, CA90806
| | - Guido Lombardi
- Laboratorio de Paleopatologia, Catedra Pedro Weiss, Universidad Peruana Cayetano Heredia, Lima15102, Peru
| | | | | | | | | | - Bret A. Beheim
- Department of Human Behavior, Ecology and Culture, Max Planck Institute for Evolutionary Anthropology, Leipzig04103, Germany
| | | | - Edmond Seabright
- Department of Anthropology, University of New Mexico, Albuquerque, NM87131
- School of Collective Intelligence, Universite Mohammed 6 Polytechnic, Ben Guerir43150, Morocco
| | - Sarah Alami
- School of Collective Intelligence, Universite Mohammed 6 Polytechnic, Ben Guerir43150, Morocco
- Department of Anthropology, University of California Santa Barbara, Santa Barbara, CA93106
| | - Angela R. Garcia
- Scientific Research Core, Phoenix Children’s Hospital, Phoenix, AZ85016
- Department of Child Health, University of Arizona, Tucson, AZ85724
| | - Kenneth Buetow
- Center for Evolution and Medicine, School of Life Sciences, Arizona State University, Tempe, AZ85287
| | - Gregory S. Thomas
- MemorialCare Health Systems, Fountain Valley, CA92708
- Division of Cardiology, University of California, Irvine, Orange, CA92868
| | - Caleb E. Finch
- Ethel Percy Andrus Gerontology Center, Leonard Davis School of Gerontology, University of Southern California, Los Angeles, CA90089
- Department of Biological Sciences, Anthropology and Psychology, University of Southern California, Los Angeles, CA90089
| | - Jonathan Stieglitz
- Institute for Advanced Study in Toulouse, Toulouse 1 Capitole University, Toulouse31000, France
| | - Benjamin C. Trumble
- Center for Evolution and Medicine, School of Human Evolution and Social Change, Arizona State University, Tempe, AZ85287
| | - Michael D. Gurven
- Department of Anthropology, University of California Santa Barbara, Santa Barbara, CA93106
| | - Andrei Irimia
- Ethel Percy Andrus Gerontology Center, Leonard Davis School of Gerontology, University of Southern California, Los Angeles, CA90089
- Corwin D. Denney Research Center, Department of Biomedical Engineering, University of Southern California, Los Angeles, CA90089
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Seabright E, Alami S, Kraft TS, Davis H, Caldwell AE, Hooper P, McAllister L, Mulville S, Veile A, von Rueden C, Trumble B, Stieglitz J, Gurven M, Kaplan H. Repercussions of patrilocal residence on mothers' social support networks among Tsimane forager-farmers. Philos Trans R Soc Lond B Biol Sci 2023; 378:20210442. [PMID: 36440570 PMCID: PMC9703270 DOI: 10.1098/rstb.2021.0442] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Accepted: 09/06/2022] [Indexed: 11/29/2022] Open
Abstract
While it is commonly thought that patrilocality is associated with worse outcomes for women and their children due to lower social support, few studies have examined whether the structure of female social networks covaries with post-marital residence. Here, we analyse scan sample data collected among Tsimane forager-farmers. We compare the social groups and activity partners of 181 women residing in the same community as their parents, their husband's parents, both or neither. Relative to women living closer to their in-laws, women living closer to their parents are less likely to be alone or solely in the company of their nuclear family (odds ratio (OR): 0.6, 95% CI: 0.3-0.9), and more likely to be observed with others when engaging in food processing and manufacturing of market or household goods, but not other activities. Women are slightly more likely to receive childcare support from outside the nuclear family when they live closer to their parents (OR = 1.8, 95% CI 0.8-3.9). Their social group size and their children's probability of receiving allocare decrease significantly with distance from their parents, but not their in-laws. Our findings highlight the importance of women's proximity to kin, but also indicate that patrilocality per se is not costly to Tsimane women. This article is part of the theme issue 'Cooperation among women: evolutionary and cross-cultural perspectives'.
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Affiliation(s)
- Edmond Seabright
- School of Collective Intelligence, Mohammed 6 Polytechnic University, Ben Guerir 43150, Morocco
- Department of Anthropology, University of New Mexico, Albuquerque, NM 87106, USA
| | - Sarah Alami
- School of Collective Intelligence, Mohammed 6 Polytechnic University, Ben Guerir 43150, Morocco
- Department of Anthropology, University of California Santa Barbara, Santa Barbara, CA 93106, USA
| | - Thomas S. Kraft
- Department of Anthropology, University of Utah, Salt Lake City, UT 84112, USA
| | - Helen Davis
- Department of Human Evolutionary Biology, Harvard University, Cambridge, MA 01451, USA
| | - Ann E. Caldwell
- Division of Endocrinology, Metabolism and Diabetes, School of Medicine, University of Colorado, Anschutz Medical Campus, Aurora, CO 80217, USA
| | - Paul Hooper
- Department of Anthropology, University of New Mexico, Albuquerque, NM 87106, USA
- Economic Science Institute, Chapman University, Orange, CA 92866, USA
| | - Lisa McAllister
- Department of Anthropology, Pennsylvania State University, University Park, PA 16802, USA
| | - Sarah Mulville
- Institute of Agriculture, University of Tennessee, Knoxville, TN 37996, USA
| | - Amanda Veile
- Department of Anthropology, Purdue University, West Lafayette, IN, USA
| | | | - Benjamin Trumble
- Center for Evolution and Medicine, Arizona State University, Tempe, AZ 85287-1701, USA
| | - Jonathan Stieglitz
- Institute for Advanced Study in Toulouse, Toulouse 1 Capitol University, Toulouse 31080, France
| | - Michael Gurven
- Department of Anthropology, University of California Santa Barbara, Santa Barbara, CA 93106, USA
| | - Hillard Kaplan
- Department of Anthropology, University of New Mexico, Albuquerque, NM 87106, USA
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Lea AJ, Garcia A, Arevalo J, Ayroles JF, Buetow K, Cole SW, Eid Rodriguez D, Gutierrez M, Highland HM, Hooper PL, Justice A, Kraft T, North KE, Stieglitz J, Kaplan H, Trumble BC, Gurven MD. Natural selection of immune and metabolic genes associated with health in two lowland Bolivian populations. Proc Natl Acad Sci U S A 2023; 120:e2207544120. [PMID: 36574663 PMCID: PMC9910614 DOI: 10.1073/pnas.2207544120] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Accepted: 09/21/2022] [Indexed: 12/28/2022] Open
Abstract
A growing body of work has addressed human adaptations to diverse environments using genomic data, but few studies have connected putatively selected alleles to phenotypes, much less among underrepresented populations such as Amerindians. Studies of natural selection and genotype-phenotype relationships in underrepresented populations hold potential to uncover previously undescribed loci underlying evolutionarily and biomedically relevant traits. Here, we worked with the Tsimane and the Moseten, two Amerindian populations inhabiting the Bolivian lowlands. We focused most intensively on the Tsimane, because long-term anthropological work with this group has shown that they have a high burden of both macro and microparasites, as well as minimal cardiometabolic disease or dementia. We therefore generated genome-wide genotype data for Tsimane individuals to study natural selection, and paired this with blood mRNA-seq as well as cardiometabolic and immune biomarker data generated from a larger sample that included both populations. In the Tsimane, we identified 21 regions that are candidates for selective sweeps, as well as 5 immune traits that show evidence for polygenic selection (e.g., C-reactive protein levels and the response to coronaviruses). Genes overlapping candidate regions were strongly enriched for known involvement in immune-related traits, such as abundance of lymphocytes and eosinophils. Importantly, we were also able to draw on extensive phenotype information for the Tsimane and Moseten and link five regions (containing PSD4, MUC21 and MUC22, TOX2, ANXA6, and ABCA1) with biomarkers of immune and metabolic function. Together, our work highlights the utility of pairing evolutionary analyses with anthropological and biomedical data to gain insight into the genetic basis of health-related traits.
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Affiliation(s)
- Amanda J. Lea
- Department of Biological Sciences, Vanderbilt University, Nashville, TN37235
| | - Angela Garcia
- Center for Evolution and Medicine, Arizona State University, Tempe, AZ85287
| | - Jesusa Arevalo
- Department of Medicine, University of California, Los Angeles, CA90095
| | - Julien F. Ayroles
- Department of Ecology and Evolution, Princeton University, Princeton, NJ08544
- Lewis Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ08544
| | - Kenneth Buetow
- Center for Evolution and Medicine, Arizona State University, Tempe, AZ85287
- School of Life Sciences, Arizona State University, Tempe, AZ85287
| | - Steve W. Cole
- Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, CA90095
- Department of Medicine, University of California, Los Angeles, CA90095
| | | | | | - Heather M. Highland
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC27516
| | - Paul L. Hooper
- Economic Science Institute, Chapman University, Orange, CA92866
| | | | - Thomas Kraft
- Department of Anthropology, University of Utah, Salt Lake City, UT84112
| | - Kari E. North
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC27516
| | | | - Hillard Kaplan
- Institute for Economics and Society, Chapman University, Orange, CA92866
| | - Benjamin C. Trumble
- Center for Evolution and Medicine, Arizona State University, Tempe, AZ85287
- School of Human Evolution and Social Change, Arizona State University, Tempe, AZ85287
| | - Michael D. Gurven
- Department of Anthropology, University of California, Santa Barbara, CA93106
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Gatz M, Mack WJ, Chui HC, Law EM, Barisano G, Sutherland ML, Sutherland JD, Eid Rodriguez D, Quispe Gutierrez R, Copajira Adrian J, Bani Cuata J, Borenstein AR, Walters EE, Irimia A, Rowan CJ, Wann LS, Allam AH, Thompson RC, Miyamoto MI, Michalik DE, Cummings DK, Seabright E, Garcia AR, Hooper PL, Kraft TS, Finch CE, Thomas GS, Stieglitz J, Trumble BC, Gurven MD, Kaplan H. Prevalence of dementia and mild cognitive impairment in indigenous Bolivian forager-horticulturalists. Alzheimers Dement 2023; 19:44-55. [PMID: 35262289 PMCID: PMC9458772 DOI: 10.1002/alz.12626] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Revised: 01/04/2022] [Accepted: 01/06/2022] [Indexed: 01/18/2023]
Abstract
INTRODUCTION We evaluated the prevalence of dementia and mild cognitive impairment (MCI) in indigenous Tsimane and Moseten, who lead a subsistence lifestyle. METHODS Participants from population-based samples ≥ 60 years of age (n = 623) were assessed using adapted versions of the Modified Mini-Mental State Examination, informant interview, longitudinal cognitive testing and brain computed tomography (CT) scans. RESULTS Tsimane exhibited five cases of dementia (among n = 435; crude prevalence = 1.2%, 95% confidence interval [CI]: 0.4, 2.7); Moseten exhibited one case (among n = 169; crude prevalence = 0.6%, 95% CI: 0.0, 3.2), all age ≥ 80 years. Age-standardized MCI prevalence was 7.7% (95% CI: 5.2, 10.3) in Tsimane and 9.8% (95% CI: 4.9, 14.6) in Moseten. Cognitive impairment was associated with visuospatial impairments, parkinsonian symptoms, and vascular calcification in the basal ganglia. DISCUSSION The prevalence of dementia in this cohort is among the lowest in the world. Widespread intracranial medial arterial calcifications suggest a previously unrecognized, non-Alzheimer's disease (AD) dementia phenotype.
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Affiliation(s)
- Margaret Gatz
- Center for Economic and Social Research, University of Southern California, Los Angeles, California, USA
| | - Wendy J Mack
- Department of Population and Public Health Sciences, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Helena C Chui
- Department of Neurology, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - E Meng Law
- Department of Neuroscience, Monash University, Melbourne, Victoria, Australia
| | - Giuseppe Barisano
- Neuroscience Graduate Program, University of Southern California, Los Angeles, California, USA
| | | | | | - Daniel Eid Rodriguez
- Institute of Biomedical Research, Faculty of Medicine, San Simon University, Cochabamba, Bolivia
| | | | | | - Jesus Bani Cuata
- Tsimane Health and Life History Project, San Borja, Beni, Bolivia
| | - Amy R Borenstein
- Division of Epidemiology, Herbert Wertheim School of Public Health and Human Longevity Science, University of California San Diego School of Medicine, La Jolla, California, USA
| | - Ellen E Walters
- Center for Economic and Social Research, University of Southern California, Los Angeles, California, USA
| | - Andrei Irimia
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, California, USA
- Corwin D. Denney Research Center, Department of Biomedical Engineering, Viterbi School of Engineering, University of Southern California, Los Angeles, California, USA
| | | | - L Samuel Wann
- Division of Cardiology, University of New Mexico, Albuquerque, New Mexico, USA
| | - Adel H Allam
- Department of Cardiology, School of Medicine, Al-Azhar University, Cairo, Egypt
| | - Randall C Thompson
- Saint Luke's Mid America Heart Institute, University of Missouri-Kansas City, Kansas City, Missouri, USA
| | | | - David E Michalik
- Memorial Care Miller Women's and Children's Hospital, Long Beach, California, USA
| | - Daniel K Cummings
- Economic Science Institute, Argyos School of Business and Economics, Chapman University, Orange, California, USA
| | - Edmond Seabright
- Department of Anthropology, University of New Mexico, Albuquerque, New Mexico, USA
| | - Angela R Garcia
- School of Human Evolution and Social Change, and Center for Evolution and Medicine, Arizona State University, Tempe, Arizona, USA
| | - Paul L Hooper
- Department of Anthropology, University of New Mexico, Albuquerque, New Mexico, USA
| | - Thomas S Kraft
- Department of Anthropology, University of California Santa Barbara, Santa Barbara, California, USA
| | - Caleb E Finch
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, California, USA
| | - Gregory S Thomas
- MemorialCare Heart & Vascular Institute, Fountain Valley, California, USA
- Division of Cardiology, University of California, Irvine, Orange, California, USA
| | | | - Benjamin C Trumble
- School of Human Evolution and Social Change, and Center for Evolution and Medicine, Arizona State University, Tempe, Arizona, USA
| | - Michael D Gurven
- Department of Anthropology, University of California Santa Barbara, Santa Barbara, California, USA
| | - Hillard Kaplan
- Economic Science Institute, Argyos School of Business and Economics, Chapman University, Orange, California, USA
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Gans BD, Neunuebel AD, Umbarger LJ, Trumble BC, Cummings DK, Wann LS, Lehenbauer KR, Mahadev A, Rodriguez DE, Michalik DE, Rowan CJ, Finch CE, Sutherland ML, Sutherland JD, Allam AH, Stieglitz J, Gurven M, Kaplan H, Thomas GS, Thompson RC. High prevalence of sternal foramina in indigenous Bolivians compared to Midwest Americans and indigenous North Americans (sternal foramina in indigenous Bolivians). Anat Sci Int 2021; 96:517-523. [PMID: 34053001 DOI: 10.1007/s12565-021-00618-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Accepted: 05/15/2021] [Indexed: 11/28/2022]
Abstract
The sternal foramen, usually an asymptomatic osteological defect, can lead to catastrophic consequences if not recognized prior to certain medical procedures. This study reports the prevalence of a sternal foramen in two South Amerindian populations compared with other published populations. We evaluated the presence of sternal foramina using thoracic computed tomography scans of 1334 (48% female) participants from two indigenous populations of Bolivia (n = 900 Tsimane, 434 Moseten). The prevalence of sternal foramina was compared to two U.S. populations of similar sex/age distribution (n = 572 Midwest Americans, 131 self-identified Native North Americans) via similar CT scans. A sternal foramen was significantly more common in the two Bolivian populations (prevalence ranging from 12.8 to 13.4%), compared to 4.4-5.1% in the two U.S. groups, consistent with prior estimates in studies from industrialized populations. Males had higher frequency of a sternal foramen compared to females in each of the four groups (OR = 1.904, 95% CI: 1.418-2.568, p < 0.001). Age was not associated with sternal foramen presence. These data show both a higher rate of sternal foramina in the South Amerindian populations versus comparator populations in North America and the highest rate of any studied living population. Although it is not possible to determine from our data the relative contribution of genetics versus early life or environmental causes to the higher rates of sternal foramen, we note that small prior studies have likewise demonstrated a higher prevalence in lower income countries. Further determination of the contributing factors warrants greater investigation and research.
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Affiliation(s)
- Benjamin D Gans
- St. Luke's Mid-America Heart Institute of Kansas City, 4330 Wornall Rd., Suite 2000, Kansas City, MO, 64111, USA.,Arkansas College of Osteopathic Medicine, Fort Smith, AR, USA
| | - Angela D Neunuebel
- St. Luke's Mid-America Heart Institute of Kansas City, 4330 Wornall Rd., Suite 2000, Kansas City, MO, 64111, USA.,University of Missouri -Kansas City, Kansas City, MO, USA
| | - Leah J Umbarger
- Arkansas College of Osteopathic Medicine, Fort Smith, AR, USA
| | - Benjamin C Trumble
- School of Human Evolution and Social Change, Center for Evolution and Medicine, Arizona State University, Tempe, AZ, USA.,Tsimane Health and Life History Project, San Borja, Bolivia, USA
| | - Daniel K Cummings
- Tsimane Health and Life History Project, San Borja, Bolivia, USA.,Economic Science Institute, Chapman University, Orange, CA, USA
| | | | - Kyle R Lehenbauer
- St. Luke's Mid-America Heart Institute of Kansas City, 4330 Wornall Rd., Suite 2000, Kansas City, MO, 64111, USA.,University of Missouri -Kansas City, Kansas City, MO, USA
| | - Ashna Mahadev
- St. Luke's Mid-America Heart Institute of Kansas City, 4330 Wornall Rd., Suite 2000, Kansas City, MO, 64111, USA.,University of Missouri -Kansas City, Kansas City, MO, USA
| | - Daniel Eid Rodriguez
- Tsimane Health and Life History Project, San Borja, Bolivia, USA.,Institute of Biomedical Research, Faculty of Medicine, San Simon University, Cochabamba, Bolivia, USA
| | - David E Michalik
- Division of Infectious Diseases, Irvine School of Medicine, University of California, Irvine, CA, USA
| | - Chris J Rowan
- Renown Institute for Heart and Vascular Health, University of Nevada School of Medicine, Reno, NV, USA
| | - Caleb E Finch
- University of Southern California Leonard Davis School of Gerontology, Los Angeles, CA, USA
| | | | | | - Adel H Allam
- Department of Cardiology, Al Azhar University, Cairo, Egypt
| | - Jonathan Stieglitz
- Tsimane Health and Life History Project, San Borja, Bolivia, USA.,Institute for Advanced Study in Toulouse, Toulouse, France
| | - Michael Gurven
- Tsimane Health and Life History Project, San Borja, Bolivia, USA.,Department of Anthropology, University of California, Santa Barbara, CA, USA
| | - Hillard Kaplan
- Tsimane Health and Life History Project, San Borja, Bolivia, USA.,Economic Science Institute, Chapman University, Orange, CA, USA
| | - Gregory S Thomas
- MemorialCare, Southern California, USA.,Division of Cardiology, University of California, Irvine, CA, USA
| | - Randall C Thompson
- St. Luke's Mid-America Heart Institute of Kansas City, 4330 Wornall Rd., Suite 2000, Kansas City, MO, 64111, USA. .,University of Missouri -Kansas City, Kansas City, MO, USA.
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9
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Kraft TS, Stieglitz J, Trumble BC, Garcia AR, Kaplan H, Gurven M. Multi-system physiological dysregulation and ageing in a subsistence population. Philos Trans R Soc Lond B Biol Sci 2020; 375:20190610. [PMID: 32951553 PMCID: PMC7540955 DOI: 10.1098/rstb.2019.0610] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/15/2020] [Indexed: 12/12/2022] Open
Abstract
Humans have the longest post-reproductive lifespans and lowest rates of actuarial ageing among primates. Understanding the links between slow actuarial ageing and physiological change is critical for improving the human 'healthspan'. Physiological dysregulation may be a key feature of ageing in industrialized populations with high burdens of chronic 'diseases of civilization', but little is known about age trajectories of physiological condition in subsistence populations with limited access to public health infrastructure. To better characterize human physiological dysregulation, we examined age trajectories of 40 biomarkers spanning the immune (n = 13 biomarkers), cardiometabolic (n = 14), musculoskeletal (n = 6) and other (n = 7) systems among Tsimane forager-horticulturalists of the Bolivian Amazon using mixed cross-sectional and longitudinal data (n = 22 115 observations). We characterized age-related changes using a multi-system statistical index of physiological dysregulation (Mahalanobis distance; Dm) that increases with age in both humans and other primates. Although individual biomarkers showed varied age profiles, we found a robust increase in age-related dysregulation for Tsimane (β = 0.17-0.18) that was marginally faster than that reported for an industrialized Western sample (β = 0.14-0.16), but slower than that of other non-human primates. We found minimal sex differences in the pace or average level of dysregulation for Tsimane. Our findings highlight some conserved patterns of physiological dysregulation in humans, consistent with the notion that somatic ageing exhibits species-typical patterns, despite cross-cultural variation in environmental exposures, lifestyles and mortality. This article is part of the theme issue 'Evolution of the primate ageing process'.
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Affiliation(s)
- Thomas S. Kraft
- Integrative Anthropological Sciences Unit, Department of Anthropology, University of California-Santa Barbara, Santa Barbara, CA 93106, USA
| | | | - Benjamin C. Trumble
- Center for Evolution and Medicine, School of Human Evolution and Social Change, Arizona State University, Tempe, AZ 85287, USA
| | - Angela R. Garcia
- Integrative Anthropological Sciences Unit, Department of Anthropology, University of California-Santa Barbara, Santa Barbara, CA 93106, USA
- Center for Evolution and Medicine, School of Human Evolution and Social Change, Arizona State University, Tempe, AZ 85287, USA
| | - Hillard Kaplan
- Economic Science Institute, Chapman University, One University Drive, Orange, CA 92866, USA
| | - Michael Gurven
- Integrative Anthropological Sciences Unit, Department of Anthropology, University of California-Santa Barbara, Santa Barbara, CA 93106, USA
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10
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Garcia AR, Blackwell AD, Trumble BC, Stieglitz J, Kaplan H, Gurven MD. Evidence for height and immune function trade-offs among preadolescents in a high pathogen population. Evol Med Public Health 2020; 2020:86-99. [PMID: 32983534 PMCID: PMC7502263 DOI: 10.1093/emph/eoaa017] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Accepted: 05/26/2020] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND In an energy-limited environment, caloric investments in one characteristic should trade-off with investments in other characteristics. In high pathogen ecologies, biasing energy allocation towards immune function over growth would be predicted, given strong selective pressures against early-life mortality. METHODOLOGY In the present study, we use flow cytometry to examine trade-offs between adaptive immune function (T cell subsets, B cells), innate immune function (natural killer cells), adaptive to innate ratio and height-for-age z scores (HAZ) among young children (N = 344; aged 2 months-8 years) in the Bolivian Amazon, using maternal BMI and child weight-for-height z scores (WHZ) as proxies for energetic status. RESULTS Markers of adaptive immune function negatively associate with child HAZ, a pattern most significant in preadolescents (3+ years). In children under three, maternal BMI appears to buffer immune and HAZ associations, while child energetic status (WHZ) moderates relationships in an unexpected direction: HAZ and immune associations are greater in preadolescents with higher WHZ. Children with low WHZ maintain similar levels of adaptive immune function, but are shorter compared to high WHZ peers. CONCLUSIONS Reduced investment in growth in favor of immunity may be necessary for survival in high pathogen contexts, even under energetic constraints. Further, genetic and environmental factors are important considerations for understanding variation in height within this population. These findings prompt consideration of whether there may be a threshold of investment into adaptive immunity required for survival in high pathogen environments, and thus question the universal relevance of height as a marker of health. LAY SUMMARY Adaptive immune function is negatively associated with child height in this high pathogen environment. Further, low weight-for-height children are shorter but maintain similar immune levels. Findings question the relevance of height as a universal health marker, given that costs and benefits of height versus immunity may be calibrated to local ecology.
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Affiliation(s)
- Angela R Garcia
- Center for Evolution and Medicine, Arizona State University, 427 E Tyler Mall, Tempe, AZ 85281, USA
- School of Life Sciences, Arizona State University, 427 E Tyler Mall, Tempe, AZ 85281, USA
| | - Aaron D Blackwell
- Department of Anthropology, Washington State University, Pullman, WA 99163, USA
| | - Benjamin C Trumble
- Center for Evolution and Medicine, Arizona State University, 427 E Tyler Mall, Tempe, AZ 85281, USA
- School of Human Evolution and Social Change, Arizona State University, 900 Cady Mall, Tempe, AZ 85281, USA
| | - Jonathan Stieglitz
- Université Toulouse 1 Capitole, espanade de l’Université 21, Allée de Brienne, Toulouse Cedex 06 31080, France
- Institute for Advanced Study in Toulouse, espanade de l’Université 21, Allée de Brienne, Toulouse Cedex 06 31080, France
| | - Hillard Kaplan
- Economic Science Institute, Chapman University, One University Drive, Orange, CA 92866, USA
| | - Michael D Gurven
- Department of Anthropology, University of California, Santa Barbara, CA 93106, USA
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11
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Hové C, Trumble BC, Anderson AS, Stieglitz J, Kaplan H, Gurven MD, Blackwell AD. Immune function during pregnancy varies between ecologically distinct populations. Evol Med Public Health 2020; 2020:114-128. [PMID: 32983537 PMCID: PMC7502269 DOI: 10.1093/emph/eoaa022] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 06/12/2020] [Accepted: 06/24/2020] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND AND OBJECTIVES Among placental mammals, females undergo immunological shifts during pregnancy to accommodate the fetus (i.e. fetal tolerance). Fetal tolerance has primarily been characterized within post-industrial populations experiencing evolutionarily novel conditions (e.g. reduced pathogen exposure), which may shape maternal response to fetal antigens. This study investigates how ecological conditions affect maternal immune status during pregnancy by comparing the direction and magnitude of immunological changes associated with each trimester among the Tsimane (a subsistence population subjected to high pathogen load) and women in the USA. METHODOLOGY Data from the Tsimane Health and Life History Project (N = 935) and the National Health and Nutrition Examination Survey (N = 1395) were used to estimate population-specific effects of trimester on differential leukocyte count and C-reactive protein (CRP), a marker of systemic inflammation. RESULTS In both populations, pregnancy was associated with increased neutrophil prevalence, reduced lymphocyte and eosinophil count and elevated CRP. Compared to their US counterparts, pregnant Tsimane women exhibited elevated lymphocyte and eosinophil counts, fewer neutrophils and monocytes and lower CRP. Total leukocyte count remained high and unchanged among pregnant Tsimane women while pregnant US women exhibited substantially elevated counts, resulting in overlapping leukocyte prevalence among all third-trimester individuals. CONCLUSIONS AND IMPLICATIONS Our findings indicate that ecological conditions shape non-pregnant immune baselines and the magnitude of immunological shifts during pregnancy via developmental constraints and current trade-offs. Future research should investigate how such flexibility impacts maternal health and disease susceptibility, particularly the degree to which chronic pathogen exposure might dampen inflammatory response to fetal antigens. LAY SUMMARY This study compares immunological changes associated with pregnancy between the Tsimane (an Amazonian subsistence population) and individuals in the USA. Results suggest that while pregnancy enhances non-specific defenses and dampens both antigen-specific immunity and parasite/allergy response, ecological conditions strongly influence immune baselines and the magnitude of shifts during gestation.
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Affiliation(s)
- Carmen Hové
- Department of Anthropology, University of California Santa Barbara, Santa Barbara, CA 93106, USA
| | - Benjamin C Trumble
- School of Human Evolution and Social Change, Center for Evolution and Medicine, Arizona State University, Tempe, AZ 85287, USA
| | - Amy S Anderson
- Department of Anthropology, University of California Santa Barbara, Santa Barbara, CA 93106, USA
| | | | - Hillard Kaplan
- Economic Science Institute, Chapman University, Orange, CA 92866, USA
| | - Michael D Gurven
- Department of Anthropology, University of California Santa Barbara, Santa Barbara, CA 93106, USA
| | - Aaron D Blackwell
- Department of Anthropology, Washington State University, Pullman, WA 99164, USA
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12
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Alami S, von Rueden C, Seabright E, Kraft TS, Blackwell AD, Stieglitz J, Kaplan H, Gurven M. Mother's social status is associated with child health in a horticulturalist population. Proc Biol Sci 2020; 287:20192783. [PMID: 32156217 PMCID: PMC7126073 DOI: 10.1098/rspb.2019.2783] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Accepted: 02/13/2020] [Indexed: 12/27/2022] Open
Abstract
High social status is often associated with greater mating opportunities and fertility for men, but do women also obtain fitness benefits of high status? Greater resource access and child survivorship may be principal pathways through which social status increases women's fitness. Here, we examine whether peer-rankings of women's social status (indicated by political influence, project leadership, and respect) positively covaries with child nutritional status and health in a community of Amazonian horticulturalists. We find that maternal political influence is associated with improved child health outcomes in models adjusting for maternal age, parental height and weight, level of schooling, household income, family size, and number of kin in the community. Children of politically influential women have higher weight-for-age (B = 0.33; 95% CI = 0.12-0.54), height-for-age (B = 0.32; 95% CI = 0.10-0.54), and weight-for-height (B = 0.24; 95% CI = 0.04-0.44), and they are less likely to be diagnosed with common illnesses (OR = 0.48; 95% CI = 0.31-0.76). These results are consistent with women leveraging their social status to enhance reproductive success through improvements in child health. We discuss these results in light of parental investment theory and the implications for the evolution of female social status in humans.
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Affiliation(s)
- Sarah Alami
- Department of Anthropology, University of California, Santa Barbara, CA 93106, USA
| | | | - Edmond Seabright
- Department of Anthropology, University of New Mexico, Albuquerque, NM 87131, USA
| | - Thomas S. Kraft
- Department of Anthropology, University of California, Santa Barbara, CA 93106, USA
| | - Aaron D. Blackwell
- Department of Anthropology, Washington State University, Pullman, WA 99163, USA
| | | | - Hillard Kaplan
- Economic Science Institute, Chapman University, Orange, CA, USA
| | - Michael Gurven
- Department of Anthropology, University of California, Santa Barbara, CA 93106, USA
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13
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Affiliation(s)
- Jonathan Stieglitz
- Université Toulouse 1 Capitole, Toulouse, France. .,Institute for Advanced Study in Toulouse, Toulouse, France.
| | - Benjamin C Trumble
- Center for Evolution and Medicine, Arizona State University, Tempe, AZ, USA.,School of Human Evolution and Social Change, Arizona State University, Tempe, AZ, USA
| | - Hillard Kaplan
- Economic Science Institute, Chapman University, Orange, CA, USA
| | - Michael Gurven
- Department of Anthropology, University of California, Santa Barbara, CA, USA
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14
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Jheeta S, Smith D. Seeing the wood for the trees: A new way to view the human intestinal microbiome and its connection with non-communicable disease. Med Hypotheses 2019; 125:70-74. [PMID: 30902154 DOI: 10.1016/j.mehy.2019.02.016] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 01/23/2019] [Accepted: 02/02/2019] [Indexed: 12/19/2022]
Abstract
Our paper briefly reviews the connection of the intestinal microbiome to the rise in non-communicable conditions related to atopic disease, obesity and mental health. We consider that the microbiome is best treated as if it were a single entity and have borrowed the terms semiochemical, allomone and kairomone (5) to describe interspecies relationship between the microbiome and ourselves (Fig. 1). We use the term dysbiosis to describe the breakdown of these relationships leading to disease (Fig. 2). As a result of this analysis we tentatively suggest that components of the microbiome assess microbial antigens in our food and pass this information back to our immune system via as yet undescribed chemical messengers: kairomones. We call these hypothetical microbial agents Sentinel Cells. Our suggestion is that atopic disease arises partly as a result of consuming processed food that has insufficient antigens to activate this kairomone feedback mechanism, which atrophies as a result. We note that this is potentially similar to the Old Friends concept of Rook and his co-workers (16). We suggest that obesity is a consequence of dysbiosis-induced waning of the output of allomone-like psychotropic compounds (including the known microbial metabolites dopamine and serotonin) leading to the weakening of the gut-brain axis and a negative effect on mental health. Although dysbiosis can occur in other ways, including antibiotic use and sterile caesarian section, we believe that all these problems can be overcome to provide a future free of these non-communicable diseases.
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15
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Yetish G, Kaplan H, Gurven M. Sleep variability and nighttime activity among Tsimane forager-horticulturalists. Am J Phys Anthropol 2018; 166:590-600. [PMID: 29989163 DOI: 10.1002/ajpa.23454] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Revised: 02/24/2018] [Accepted: 02/26/2018] [Indexed: 12/22/2022]
Abstract
OBJECTIVES A common presumption in sleep research is that "normal" human sleep should show high night-to-night consistency. Yet, intra-individual sleep variation in small-scale subsistence societies has never been studied to test this idea. In this study, we assessed the degree of nightly variation in sleep patterns among Tsimane forager-horticulturalists in Bolivia, and explored possible drivers of the intra-individual variability. METHODS We actigraphically recorded sleep among 120 Tsimane adults (67 female), aged 18-91, for an average of 4.9 nights per person using the Actigraph GT3X and Philips Respironics Actiwatch 2. We assessed intra-individual variation using intra-class correlations and average deviation from each individual's average sleep duration, onset, and offset times ( ɛ¯). RESULTS Only 31% of total variation in sleep duration was due to differences among different individuals, with the remaining 69% due to nightly differences within the same individuals. We found no statistically significant differences in Tsimane sleep duration by day-of-the-week. Nightly variation in sleep duration was driven by highly variable sleep onset, especially for men. Nighttime activities associated with later sleep onset included hunting, fishing, housework, and watching TV. CONCLUSIONS In contrast to nightly sleep variation in the United States being driven primarily by "sleeping-in" on weekends, Tsimane sleep variation, while comparable to that observed in the United States, was driven by changing "bedtimes," independent of day-of-the-week. We propose that this variation may reflect adaptive responses to changing opportunity costs to sleep/nighttime activity.
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Affiliation(s)
- Gandhi Yetish
- Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, Los Angeles, California, United States of America
| | - Hillard Kaplan
- Economic Science Institute, Chapman University, Orange, California, United States of America
| | - Michael Gurven
- Department of Anthropology, University of California, Santa Barbara, Santa Barbara, California, United States of America
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16
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van der Linden D, Dunkel CS, Figueredo AJ, Gurven M, von Rueden C, Woodley of Menie MA. How Universal Is the General Factor of Personality? An Analysis of the Big Five in Forager Farmers of the Bolivian Amazon. J Cross Cult Psychol 2018; 49:1081-1097. [PMID: 30046184 PMCID: PMC6047301 DOI: 10.1177/0022022118774925] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
In various personality models, such as the Big Five, a consistent higher order general factor of personality (GFP) can be identified. One view in the literature is that the GFP reflects general social effectiveness. Most GFP studies, however, have been conducted in Western, educated, industrialized, and rich democracies (WEIRD). Therefore, to address the question of the universality of the GFP, we test whether the GFP can also be identified in a preliterate indigenous sample of Tsimane by using self-reports, spouse reports, and interviewer ratings. In the Tsimane, a viable GFP could be identified and the intercorrelations between personality traits were significantly stronger than in samples from industrial countries. The GFP correlated with the ratings of social engagement. In addition, self and spouse ratings of the GFP overlapped. Overall, the findings are in line with the notion that the GFP is a human universal and a substantive personality factor reflecting social effectiveness.
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17
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Costa ME, Trumble B, Kaplan H, Gurven MD. Child nutritional status among births exceeding ideal family size in a high fertility population. Matern Child Nutr 2018; 14:e12625. [PMID: 29888858 DOI: 10.1111/mcn.12625] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Revised: 04/10/2018] [Accepted: 04/19/2018] [Indexed: 11/27/2022]
Abstract
Ideal family size (IFS) is measured in social surveys to indicate unmet need for contraception and impending shifts in fertility behaviour. Whether exceeding IFS affects parental behaviour in ways that result in lower investments in child nutrition, well-being, and educational attainment is not known. This study examines parental IFS and the association between exceeding stated ideals and child nutritional status in a high-fertility, high-mortality population in the Bolivian Amazon. Height-for-age z-scores, weight-for-age z-scores, weight-for-height z-scores, stunting, haemoglobin, and anaemia status in 638 children aged 0-5 years are predicted as a function of birth order in relation to parental IFS, adjusting for household characteristics and mother and child random effects. Children of birth orders above paternal IFS experience higher weight-for-age z-scores when living further away from the market town of San Borja, consistent with underlying motivations for higher IFS and lower human capital investment in children in more remote areas (β = .009, p = .027). Overall, we find no statistical evidence that birth orders in excess of parental ideals are associated with compromised child nutrition below age 2, a period of intensive breastfeeding in this population. Despite a vulnerability to nutritional deficiencies postweaning for children age 2-5, there was no association between birth order in excess of parental ideals and lower nutritional status. Further studies examining this association at various stages of the fertility transition will elucidate whether reported ideal or optimal family sizes are flexible as trade-offs between quality and quantity of children shift during the transition to lower fertility.
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Affiliation(s)
- Megan E Costa
- T. Denny Sanford School of Social and Family Dynamics, Arizona State University, Tempe, Arizona, USA
| | - Benjamin Trumble
- School of Human Evolution and Social Change and Center for Evolution and Medicine, Arizona State University, Tempe, Arizona, USA
| | - Hillard Kaplan
- Department of Health Economics and Anthropology, Economic Science Institute, Argyros School of Business and Economics Chapman University, Orange, California, USA
| | - Michael D Gurven
- Department of Anthropology, University of California Santa Barbara, Santa Barbara, California, USA
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18
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Abstract
We here describe two apparent paradoxes concerning high CRP levels and NCD risk. One has emerged from observational studies in the Amazon region showing that the indigenous Tsimane in Bolivia appear protected against non-communicable diseases (NCDs) such as obesity, type 2 diabetes, and cardiovascular diseases despite increased inflammatory markers. These findings stand in contrast to Western societies, where an increasing body of evidence demonstrates that low-grade-inflammation is the driver of NCDs. The second paradox has emerged from two field studies (Eifel studies) conducted in 2013 and 2014 with Westerners who returned to a simulated Palaeolithic lifestyle in a National park for 4 days. We had detected elevated inflammation markers, despite otherwise anti-inflammatory effects of these interventions as indicated by metabolic blood parameters. We here propose three hypotheses for this second inflammatory paradox.
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Affiliation(s)
- Jens Freese
- Institute of Outdoor Sports and Environmental Science, German Sports University Cologne, Cologne, 50933, Germany
| | - Rainer Johannes Klement
- Department of Radiotherapy and Radiation Oncology, Leopoldina Hospital Schweinfurt, Schweinfurt, 97422, Germany
| | - Helmut Lötzerich
- Institute of Outdoor Sports and Environmental Science, German Sports University Cologne, Cologne, 50933, Germany
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19
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Alami S, Stieglitz J, Kaplan H, Gurven M. Low perceived control over health is associated with lower treatment uptake in a high mortality population of Bolivian forager-farmers. Soc Sci Med 2018; 200:156-165. [PMID: 29421462 PMCID: PMC5893402 DOI: 10.1016/j.socscimed.2018.01.017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Revised: 01/13/2018] [Accepted: 01/15/2018] [Indexed: 01/29/2023]
Abstract
Indigenous people worldwide suffer from higher rates of morbidity and mortality than neighboring populations. In addition to having limited access to public health infrastructure, indigenous people may also have priorities and health perceptions that deter them from seeking adequate modern healthcare. Here we propose that living in a harsh and unpredictable environment reduces motivation to pursue deliberate, costly action to improve health outcomes. We assess whether variation in Health Locus of Control (HLC), a psychological construct designed to capture self-efficacy with respect to health, explains variation in treatment uptake behavior among Tsimane Amerindians (N = 690; age range: 40-89 years; 55.8% female; data collection: 2008-2012), a high mortality and morbidity indigenous population in the Bolivian Amazon, Beni Department. Comparisons with two industrialized populations in Japan (Miyagi prefecture; e0 = 76.6 years) and the United Kingdom (Caerphilly county borough; e0 = 81.2 years) confirm that Tsimane (e0 = 54.1 years) have a more externalized HLC. Multilevel level models were used to investigate whether HLC predicts treatment uptake, and mediates the relationship between modernization and treatment uptake. External HLC scores were predictive of treatment outcomes: Powerful others scores were positively associated with probability of receiving modern treatment (adjusted odds ratio [OR] = 1.33), while Chance scores were negatively associated with probability of receiving modern treatment (adjusted OR = 0.76). We found no effects, however, of Internal HLC or educational capital on treatment uptake. Overall, our findings indicate that health-related decision-making is influenced more by a psychological orientation affecting self-efficacy, shaped in part by perceptions of environmental unpredictability and harshness, than by limited knowledge, education or other indicators of modernization.
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Affiliation(s)
- Sarah Alami
- University of California, Santa Barbara, Department of Anthropology, Santa Barbara, CA 93106, United States.
| | | | - Hillard Kaplan
- Chapman University, Economic Science Institute, Orange, CA 92866, United States
| | - Michael Gurven
- University of California, Santa Barbara, Department of Anthropology, Santa Barbara, CA 93106, United States.
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Stieglitz J, Trumble BC, Kaplan H, Gurven M. Horticultural activity predicts later localized limb status in a contemporary pre-industrial population. Am J Phys Anthropol 2017; 163:425-436. [PMID: 28345788 DOI: 10.1002/ajpa.23214] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Revised: 01/30/2017] [Accepted: 03/10/2017] [Indexed: 12/25/2022]
Abstract
OBJECTIVES Modern humans may have gracile skeletons due to low physical activity levels and mechanical loading. Tests using pre-historic skeletons are limited by the inability to assess behavior directly, while modern industrialized societies possess few socio-ecological features typical of human evolutionary history. Among Tsimane forager-horticulturalists, we test whether greater activity levels and, thus, increased loading earlier in life are associated with greater later-life bone status and diminished age-related bone loss. MATERIALS AND METHODS We used quantitative ultrasonography to assess radial and tibial status among adults aged 20+ years (mean ± SD age = 49 ± 15; 52% female). We conducted systematic behavioral observations to assess earlier-life activity patterns (mean time lag between behavioural observation and ultrasound = 12 years). For a subset of participants, physical activity was again measured later in life, via accelerometry, to determine whether earlier-life time use is associated with later-life activity levels. Anthropometric and demographic data were collected during medical exams. RESULTS Structural decline with age is reduced for the tibia (female: -0.25 SDs/decade; male: 0.05 SDs/decade) versus radius (female: -0.56 SDs/decade; male: -0.20 SDs/decade), which is expected if greater loading mitigates bone loss. Time allocation to horticulture, but not hunting, positively predicts later-life radial status (βHorticulture = 0.48, p = 0.01), whereas tibial status is not significantly predicted by subsistence or sedentary leisure participation. DISCUSSION Patterns of activity- and age-related change in bone status indicate localized osteogenic responses to loading, and are generally consistent with the logic of bone functional adaptation. Nonmechanical factors related to subsistence lifestyle moderate the association between activity patterns and bone structure.
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Affiliation(s)
- Jonathan Stieglitz
- Institute for Advanced Study in Toulouse, Université de Toulouse, France.,Department of Anthropology, University of New Mexico, Albuquerque, New Mexico
| | - Benjamin C Trumble
- Center for Evolution and Medicine, Arizona State University, Tempe, Arizona.,School of Human Evolution and Social Change, Arizona State University, Tempe, Arizona
| | - Hillard Kaplan
- Department of Anthropology, University of New Mexico, Albuquerque, New Mexico
| | - Michael Gurven
- Department of Anthropology, University of California, Santa Barbara, California
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Trumble BC, Stieglitz J, Blackwell AD, Allayee H, Beheim B, Finch CE, Gurven M, Kaplan H. Apolipoprotein E4 is associated with improved cognitive function in Amazonian forager-horticulturalists with a high parasite burden. FASEB J 2016; 31:1508-1515. [PMID: 28031319 DOI: 10.1096/fj.201601084r] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Accepted: 12/12/2016] [Indexed: 12/20/2022]
Abstract
The apolipoprotein E4 (E4) allele is present worldwide, despite its associations with higher risk of cardiovascular morbidity, accelerated cognitive decline during aging, and Alzheimer's disease (AD). The E4 allele is especially prevalent in some tropical regions with a high parasite burden. Equatorial populations also face a potential dual burden of high E4 prevalence combined with parasitic infections that can also reduce cognitive performance. We examined the interactions of E4, parasite burden, and cognitive performance in a traditional, nonindustrialized population of Amazonian forager-horticulturalists (N = 372) to test whether E4 protects against cognitive decline in environments with a heavy pathogen burden. Contrary to observations in industrial populations, older adult E4 carriers with high parasite burdens either maintained or showed slight improvements in cognitive performance, whereas non-E4 carriers with a high parasite burden showed reduced cognitive performance. Being an E4 carrier is the strongest risk factor to date of AD and cognitive decline in industrial populations; it is associated with greater cognitive performance in individuals facing a high parasite and pathogen load, suggesting advantages to the E4 allele under certain environmental conditions. The current mismatch between postindustrial hygienic lifestyles and active parasite-rich environs may be critical for understanding genetic risk for cognitive aging.-Trumble, B. C., Stieglitz, J., Blackwell, A. D., Allayee, H., Beheim, B., Finch, C. E., Gurven, M., Kaplan, H. Apolipoprotein E4 is associated with improved cognitive function in Amazonian forager-horticulturalists with a high parasite burden.
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Affiliation(s)
- Benjamin C Trumble
- School of Human Evolution and Social Change, Arizona State University, Tempe, Arizona, USA; .,Center for Evolution and Medicine, Arizona State University, Tempe, Arizona, USA
| | - Jonathan Stieglitz
- Institute for Advanced Study in Toulouse, Toulouse, France.,Department of Anthropology, University of New Mexico, Albuquerque, New Mexico, USA
| | - Aaron D Blackwell
- Department of Anthropology, University of California, Santa Barbara, Santa Barbara, California, USA
| | - Hooman Allayee
- Department of Preventive Medicine, University of Southern California, Los Angeles, California, USA.,Institute for Genetic Medicine, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Bret Beheim
- Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Caleb E Finch
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, California, USA.,Dornsife College, University of Southern California, Los Angeles, California, USA
| | - Michael Gurven
- Department of Anthropology, University of California, Santa Barbara, Santa Barbara, California, USA
| | - Hillard Kaplan
- Department of Anthropology, University of New Mexico, Albuquerque, New Mexico, USA
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Blackwell AD, Urlacher SS, Beheim B, von Rueden C, Jaeggi A, Stieglitz J, Trumble BC, Gurven M, Kaplan H. Growth references for Tsimane forager-horticulturalists of the Bolivian Amazon. Am J Phys Anthropol 2016; 162:441-461. [PMID: 28218400 DOI: 10.1002/ajpa.23128] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Revised: 10/12/2016] [Accepted: 10/20/2016] [Indexed: 11/10/2022]
Abstract
OBJECTIVES Growth standards and references currently used to assess population and individual health are derived primarily from urban populations, including few individuals from indigenous or subsistence groups. Given environmental and genetic differences, growth may vary in these populations. Thus, there is a need to assess whether international standards are appropriate for all populations, and to produce population specific references if growth differs. Here we present and assess growth references for the Tsimane, an indigenous population of Bolivian forager-horticulturalists. METHODS Mixed cross-sectional/longitudinal anthropometrics (9,614 individuals; 30,118 observations; ages 0-29 years) were used to generate centile curves and Lambda-Mu-Sigma (LMS) tables for height-for-age, weight-for-age, body mass index (BMI)-for-age, and weight-for-height (WFH) using Generalized Additive Models for Location Shape and Scale (GAMLSS). Velocity curves were generated using SuperImposition by Translation and Rotation (SITAR). Tsimane ≤5 years were compared to World Health Organization (WHO) standards while those >5 years were compared to WHO school age references. All ages were compared to published references for Shuar forager-horticulturalists of the Ecuadorian Amazon. RESULTS Tsimane growth differs from WHO values in height and weight, but is similar for BMI and WFH. Tsimane growth is characterized by slow height velocity in childhood and early adolescent peak height velocity at 11.3 and 13.2 years for girls and boys. Tsimane growth patterns are similar to Shuar, suggesting shared features of growth among indigenous South Americans. CONCLUSIONS International references for BMI-for-age and WFH are likely appropriate for Tsimane, but differences in height-for-age and weight-for-age suggest Tsimane specific references may be useful for these measures.
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Affiliation(s)
- Aaron D Blackwell
- Department of Anthropology, University of California Santa Barbara, California.,Tsimane Health and Life History Project, San Borja, Bolivia
| | - Samuel S Urlacher
- Department of Anthropology, Hunter College, City University of New York, New York
| | - Bret Beheim
- Tsimane Health and Life History Project, San Borja, Bolivia.,Department of Human Behavior, Ecology and Culture, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany.,Department of Anthropology, University of New Mexico, Albuquerque, New Mexico
| | - Christopher von Rueden
- Tsimane Health and Life History Project, San Borja, Bolivia.,Jepson School of Leadership Studies, University of Richmond, Richmond, Virginia
| | - Adrian Jaeggi
- Tsimane Health and Life History Project, San Borja, Bolivia.,Department of Anthropology, Emory University, Atlanta, Georgia
| | - Jonathan Stieglitz
- Tsimane Health and Life History Project, San Borja, Bolivia.,Department of Anthropology, University of New Mexico, Albuquerque, New Mexico.,Institute for Advanced Study in Toulouse, Toulouse, France
| | - Benjamin C Trumble
- Department of Anthropology, University of California Santa Barbara, California.,Tsimane Health and Life History Project, San Borja, Bolivia.,Center for Evolution and Medicine, Arizona State University, Tempe, Arizona.,School of Human Evolution and Social Change, Arizona State University, Tempe, Arizona
| | - Michael Gurven
- Department of Anthropology, University of California Santa Barbara, California.,Tsimane Health and Life History Project, San Borja, Bolivia
| | - Hillard Kaplan
- Tsimane Health and Life History Project, San Borja, Bolivia.,Department of Anthropology, University of New Mexico, Albuquerque, New Mexico
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Trumble BC, Blackwell AD, Stieglitz J, Thompson ME, Suarez IM, Kaplan H, Gurven M. Associations between male testosterone and immune function in a pathogenically stressed forager-horticultural population. Am J Phys Anthropol 2016; 161:494-505. [PMID: 27465811 DOI: 10.1002/ajpa.23054] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Revised: 06/28/2016] [Accepted: 07/06/2016] [Indexed: 01/24/2023]
Abstract
OBJECTIVES Despite well-known fitness advantages to males who produce and maintain high endogenous testosterone levels, such phenotypes may be costly if testosterone-mediated investment in reproductive effort trade-off against investment in somatic maintenance. Previous studies of androgen-mediated trade-offs in human immune function find mixed results, in part because most studies either focus on a few indicators of immunity, are confounded by phenotypic correlation, or are observational. Here the association between male endogenous testosterone and 13 circulating cytokines are examined before and after ex vivo antigen stimulation with phytohemagglutinin (PHA) and lipopolysaccharides (LPS) in a high pathogen population of Bolivian forager-horticulturalists. MATERIALS AND METHODS A Milliplex 13-plex cytokine panel measured cytokine concentration in whole blood samples from 109 Tsimane men aged 40-89 (median = 50 years) before and after antigen stimulation with PHA and LPS. Urinary testosterone was measured via enzyme immunoassay, demographic, and anthropometric data were collected as part of the Tsimane Health and Life History Project. RESULTS Higher endogenous testosterone was associated with down-regulated responses in all cytokines after PHA stimulation (but significantly in only 2/13 cytokines), controlling for age and body mass index. In contrast, testosterone was not significantly associated with down-regulation of cytokines after LPS stimulation. MANOVAs indicate that men with higher testosterone showed reduced cytokine responses to PHA compared with LPS (p = 0.0098). DISCUSSION Endogenous testosterone appears to be immunomodulatory rather than immunosuppressive. Potentially costlier forms of immune activation like those induced by PHA (largely T-cell biased immune activation) are down-regulated in men with higher testosterone, but testosterone has less impact on potentially less costly immune activation following LPS stimulation (largely B-cell mediated immunity).
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Affiliation(s)
- Benjamin C Trumble
- Department of Anthropology, University of California Santa Barbara, Santa Barbara, CA. .,Tsimane Health and Life History Project, San Borja, Bolivia.
| | - Aaron D Blackwell
- Department of Anthropology, University of California Santa Barbara, Santa Barbara, CA.,Tsimane Health and Life History Project, San Borja, Bolivia
| | - Jonathan Stieglitz
- Tsimane Health and Life History Project, San Borja, Bolivia.,Department of Anthropology, University of New Mexico, Albuquerque, NM.,Institute for Advanced Study in Toulouse, Toulouse, France
| | | | | | - Hillard Kaplan
- Tsimane Health and Life History Project, San Borja, Bolivia.,Department of Anthropology, University of New Mexico, Albuquerque, NM
| | - Michael Gurven
- Department of Anthropology, University of California Santa Barbara, Santa Barbara, CA.,Tsimane Health and Life History Project, San Borja, Bolivia
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Gurven MD, Trumble BC, Stieglitz J, Yetish G, Cummings D, Blackwell AD, Beheim B, Kaplan HS, Pontzer H. High resting metabolic rate among Amazonian forager-horticulturalists experiencing high pathogen burden. Am J Phys Anthropol 2016; 161:414-425. [PMID: 27375044 DOI: 10.1002/ajpa.23040] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Revised: 06/07/2016] [Accepted: 06/12/2016] [Indexed: 12/27/2022]
Abstract
OBJECTIVES Resting metabolic rate (RMR) reflects energetic costs of homeostasis and accounts for 60 to 75% of total energy expenditure (TEE). Lean mass and physical activity account for much RMR variability, but the impact of prolonged immune activation from infection on human RMR is unclear in naturalistic settings. We evaluate the effects of infection on mass-corrected RMR among Bolivian forager-horticulturalists, and assess whether RMR declines more slowly with age than in hygienic sedentary populations, as might be expected if older adults experience high pathogen burden. MATERIALS AND METHODS RMR was measured by indirect calorimetry (Fitmate MED, Cosmed) in 1,300 adults aged 20 to 90 and TEE was measured using doubly labeled water (n = 40). Immune biomarkers, clinical diagnoses, and anthropometrics were collected by the Tsimane Health and Life History Project. RESULTS Tsimane have higher RMR and TEE than people in sedentary industrialized populations. Tsimane RMR is 18 to 47% (women) and 22 to 40% (men) higher than expected using six standard prediction equations. Tsimane mass-corrected TEE is similarly elevated compared to Westerners. Elevated leukocytes and helminths are associated with excess RMR in multivariate regressions, and jointly result in a predicted excess RMR of 10 to 15%. After age 40, RMR declines by 69 kcal/decade (p < .0001). Controlling for lean mass and height accounts for 71% of age-related RMR decline, and adding indicators of infection minimally affects the age slope. The residual level of age-related decline from age 40 is 1.2% per decade. CONCLUSION High pathogen burden may lead to higher metabolic costs, which may be offset by smaller body mass or other energy-sparing mechanisms.
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Affiliation(s)
- Michael D Gurven
- Department of Anthropology, University of California Santa Barbara, Santa Barbara, CA.
| | - Benjamin C Trumble
- Department of Anthropology, University of California Santa Barbara, Santa Barbara, CA
| | | | - Gandhi Yetish
- Department of Anthropology, University of New Mexico, Albuquerque, NM
| | - Daniel Cummings
- Department of Anthropology, University of New Mexico, Albuquerque, NM
| | - Aaron D Blackwell
- Department of Anthropology, University of California Santa Barbara, Santa Barbara, CA
| | - Bret Beheim
- Department of Anthropology, University of New Mexico, Albuquerque, NM
| | - Hillard S Kaplan
- Department of Anthropology, University of New Mexico, Albuquerque, NM
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Blackwell AD, Trumble BC, Maldonado Suarez I, Stieglitz J, Beheim B, Snodgrass JJ, Kaplan H, Gurven M. Immune function in Amazonian horticulturalists. Ann Hum Biol 2016; 43:382-96. [PMID: 27174705 DOI: 10.1080/03014460.2016.1189963] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
BACKGROUND Amazonian populations are exposed to diverse parasites and pathogens, including protozoal, bacterial, fungal and helminthic infections. Yet much knowledge of the immune system is based on industrialised populations where these infections are relatively rare. AIM This study examines distributions and age-related differences in 22 measures of immune function for Bolivian forager-horticulturalists and US and European populations. SUBJECTS AND METHODS Subjects were 6338 Tsimane aged 0-90 years. Blood samples collected between 2004-2014 were analysed for 5-part blood differentials, C-reactive protein, erythrocyte sedimentation rate (ESR) and total immunoglobulins E, G, A and M. Flow cytometry was used to quantify naïve and non-naïve CD4 and CD8 T cells, natural killer cells, and B cells. RESULTS Compared to reference populations, Tsimane have elevated levels of most immunological parameters, particularly immunoglobulins, eosinophils, ESR, B cells, and natural killer cells. However, monocytes and basophils are reduced and naïve CD4 cells depleted in older age groups. CONCLUSION Tsimane ecology leads to lymphocyte repertoires and immunoglobulin profiles that differ from those observed in industrialised populations. These differences have consequences for disease susceptibility and co-vary with patterns of other life history traits, such as growth and reproduction.
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Affiliation(s)
- Aaron D Blackwell
- a Department of Anthropology , University of California , Santa Barbara , CA , USA ;,b Tsimane Health and Life History Project , San Borja , Bolivia
| | - Benjamin C Trumble
- a Department of Anthropology , University of California , Santa Barbara , CA , USA ;,b Tsimane Health and Life History Project , San Borja , Bolivia ;,c Center for Evolutionary Medicine, Arizona State University , Tempe , AZ , USA ;,d School of Human Evolution and Social Change, Arizona State University , Tempe , AZ , USA
| | | | - Jonathan Stieglitz
- b Tsimane Health and Life History Project , San Borja , Bolivia ;,e Department of Anthropology , University of New Mexico , Albuquerque , NM , USA ;,f Institute for Advanced Study in Toulouse , Toulouse , France
| | - Bret Beheim
- b Tsimane Health and Life History Project , San Borja , Bolivia ;,e Department of Anthropology , University of New Mexico , Albuquerque , NM , USA
| | - J Josh Snodgrass
- g Department of Anthropology , University of Oregon , Eugene , OR , USA
| | - Hillard Kaplan
- b Tsimane Health and Life History Project , San Borja , Bolivia ;,e Department of Anthropology , University of New Mexico , Albuquerque , NM , USA
| | - Michael Gurven
- a Department of Anthropology , University of California , Santa Barbara , CA , USA ;,b Tsimane Health and Life History Project , San Borja , Bolivia
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Stieglitz J, Trumble BC, Thompson ME, Blackwell AD, Kaplan H, Gurven M. Depression as sickness behavior? A test of the host defense hypothesis in a high pathogen population. Brain Behav Immun 2015; 49:130-9. [PMID: 26044086 DOI: 10.1016/j.bbi.2015.05.008] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2015] [Revised: 05/15/2015] [Accepted: 05/17/2015] [Indexed: 12/23/2022] Open
Abstract
Sadness is an emotion universally recognized across cultures, suggesting it plays an important functional role in regulating human behavior. Numerous adaptive explanations of persistent sadness interfering with daily functioning (hereafter "depression") have been proposed, but most do not explain frequent bidirectional associations between depression and greater immune activation. Here we test several predictions of the host defense hypothesis, which posits that depression is part of a broader coordinated evolved response to infection or tissue injury (i.e. "sickness behavior") that promotes energy conservation and reallocation to facilitate immune activation. In a high pathogen population of lean and relatively egalitarian Bolivian forager-horticulturalists, we test whether depression and its symptoms are associated with greater baseline concentration of immune biomarkers reliably associated with depression in Western populations (i.e. tumor necrosis factor alpha [TNF-α], interleukin-1 beta [IL-1β], interleukin-6 [IL-6], and C-reactive protein [CRP]). We also test whether greater pro-inflammatory cytokine responses to ex vivo antigen stimulation are associated with depression and its symptoms, which is expected if depression facilitates immune activation. These predictions are largely supported in a sample of older adult Tsimane (mean±SD age=53.2±11.0, range=34-85, n=649) after adjusting for potential confounders. Emotional, cognitive and somatic symptoms of depression are each associated with greater immune activation, both at baseline and in response to ex vivo stimulation. The association between depression and greater immune activation is therefore not unique to Western populations. While our findings are not predicted by other adaptive hypotheses of depression, they are not incompatible with those hypotheses and future research is necessary to isolate and test competing predictions.
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Gurven M, Jaeggi AV, von Rueden C, Hooper PL, Kaplan H. Does market integration buffer risk, erode traditional sharing practices and increase inequality? A test among Bolivian forager-farmers. Hum Ecol Interdiscip J 2015; 43:515-30. [PMID: 26526638 PMCID: PMC4624453 DOI: 10.1007/s10745-015-9764-y] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Sharing and exchange are common practices for minimizing food insecurity in rural populations. The advent of markets and monetization in egalitarian indigenous populations presents an alternative means of managing risk, with the potential impact of eroding traditional networks. We test whether market involvement buffers several types of risk and reduces traditional sharing behavior among Tsimane Amerindians of the Bolivian Amazon. Results vary based on type of market integration and scale of analysis (household vs. village), consistent with the notion that local culture and ecology shape risk management strategies. Greater wealth and income were unassociated with the reliance on others for food, or on reciprocity, but wealth was associated with a greater proportion of food given to others (i.e., giving intensity) and a greater number of sharing partners (i.e., sharing breadth). Across villages, greater mean income was negatively associated with reciprocity, but economic inequality was positively associated with giving intensity and sharing breadth. Incipient market integration does not necessarily replace traditional buffering strategies but instead can often enhance social capital.
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Affiliation(s)
- Michael Gurven
- Department of Anthropology, University of California-Santa Barbara, Santa Barbara, CA 93106
- Corresponding author, , 805-893-2202
| | - Adrian V. Jaeggi
- Department of Anthropology, University of California-Santa Barbara, Santa Barbara, CA 93106
| | - Chris von Rueden
- Jepson School of Leadership Studies, University of Richmond, Richmond VA 23173
| | - Paul L. Hooper
- Department of Anthropology, Emory University, Atlanta, GA 30322
| | - Hillard Kaplan
- Department of Anthropology, University of New Mexico, Albuquerque, NM 87131
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Stieglitz J, Beheim BA, Trumble BC, Madimenos FC, Kaplan H, Gurven M. Low mineral density of a weight-bearing bone among adult women in a high fertility population. Am J Phys Anthropol 2014; 156:637-48. [PMID: 25488367 DOI: 10.1002/ajpa.22681] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Revised: 11/13/2014] [Accepted: 11/24/2014] [Indexed: 12/20/2022]
Abstract
Evolutionary theories of aging posit that greater reproductive effort causes somatic decline given a fundamental trade-off between investing energy in reproduction and repair. Few studies in high fertility human populations support this hypothesis, and problems of phenotypic correlation can obscure the expected trade-off between reproduction and somatic condition. This cross-sectional study investigates whether greater reproductive effort is associated with reduced calcaneal bone mineral density (BMD) among female Tsimane forager-farmers of lowland Bolivia. We also investigate whether female Tsimane BMD values are lower than sex- and age-matched US reference values, despite the fact that Tsimane engage in higher physical activity levels that can increase mechanical loading. To measure calcaneal BMD, quantitative ultrasonography was performed on 130 women (mean ± SD age = 36.6 ± 15.7, range = 15-75) that were recruited regardless of past or current reproductive status. Anthropometric and demographic data were collected during routine medical exams. As predicted, higher parity, short inter-birth interval, and earlier age at first birth are associated with reduced BMD among Tsimane women after adjusting for potential confounders. Population-level differences are apparent prior to the onset of reproduction, and age-related decline in BMD is greater among Tsimane compared with American women. Greater cumulative reproductive burden may lower calcaneal BMD individually and jointly with other lifestyle and heritable factors. Fitness impacts of kin transfers in adulthood may determine the value of investments in bone remodeling, and thus affect selection on age-profiles of bone mineral loss.
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Affiliation(s)
- Jonathan Stieglitz
- Department of Anthropology, University of New Mexico, Albuquerque, NM, 87131; Institute for Advanced Study in Toulouse, 31015, Toulouse Cedex 6, France
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Stieglitz J, Schniter E, von Rueden C, Kaplan H, Gurven M. Functional Disability and Social Conflict Increase Risk of Depression in Older Adulthood Among Bolivian Forager-Farmers. J Gerontol B Psychol Sci Soc Sci 2014; 70:948-56. [PMID: 24986182 DOI: 10.1093/geronb/gbu080] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Accepted: 05/21/2014] [Indexed: 11/14/2022] Open
Abstract
OBJECTIVES To present an explanatory framework for depression in older adulthood in a small-scale society. We propose that depression is a consequence of functional disability, which can reduce subsistence productivity and resource transfers within and across generations. Social conflict can also disrupt resource flows and should be associated with depression. METHOD To evaluate depression among Tsimane forager-farmers of Bolivia, we developed a reliable interview based on focus groups and a review of validated depression scales. Older adults (mean ± SD age = 62 ± 9, n = 325) were recruited regardless of their health status. Demographic, economic, and medical data were collected during annual censuses and routine medical exams. RESULTS Depression is associated with reduced energetic status, greater physical limitations, and reduced subsistence involvement after controlling for potential confounds such as age, sex, number of reported unresolved conflicts, and market involvement. Depression is also associated with greater reported conflict, particularly with non-kin. DISCUSSION Tsimane depression is associated with disability, reduced subsistence productivity, and interpersonal conflict, all of which can disrupt resource flows. Depression appears to be a response to conditions regularly experienced over human history, and not simply a by-product of modernity.
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Affiliation(s)
| | - Eric Schniter
- Economic Sciences Institute, Chapman University, California
| | | | - Hillard Kaplan
- Department of Anthropology, University of New Mexico. Economic Sciences Institute, Chapman University, California
| | - Michael Gurven
- Integrative Anthropological Sciences Unit, University of California-Santa Barbara
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Trumble BC, Smith EA, O'Connor KA, Kaplan HS, Gurven MD. Successful hunting increases testosterone and cortisol in a subsistence population. Proc Biol Sci 2013; 281:20132876. [PMID: 24335989 DOI: 10.1098/rspb.2013.2876] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Controversy over the adaptive significance of male hunting in subsistence societies hinges on the relative importance of familial provisioning and mate-quality signalling. This paper examines the proximate and ultimate motivations of hunting behaviour from a neuroendocrine perspective, using salivary testosterone and cortisol data collected before, during and after hunting focal follows from 31 Tsimane hunters aged 18-82 years. Despite circadian declines in hormone levels, testosterone and cortisol of Tsimane hunters increased at the time of a kill, and remained high as successful hunters returned home. Previous studies of hormonal changes during competitions find that high-stakes and success in the presence of relevant audiences result in increased neuroendocrine arousal. If men hunt primarily to provision their families, then an additional audience would not be expected to impact testosterone or cortisol, nor would the size of the animal killed. However, if signalling male quality by 'showing off' was a larger relative driver of men's hunting behaviour, one would expect greater hormonal response in cases where men returned with large sharable kills, especially in the presence of community members. Consistent with provisioning models of male hunting motivation, neither kill size nor encountering an audience of villagers while returning from hunting was associated with hormonal changes for successful hunters.
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Affiliation(s)
- Benjamin C Trumble
- Institute for Social, Behavioral, and Economic Research, University of California Santa Barbara, , Santa Barbara, CA 93106-3210, USA, Integrative Anthropological Sciences, Department of Anthropology, University of California Santa Barbara, , Santa Barbara, CA 93106-3210, USA, Department of Anthropology, University of Washington, , Seattle, WA, USA, Center for Studies in Demography and Ecology, University of Washington, , Seattle, WA, USA, Department of Anthropology, University of New Mexico, , Albuquerque, NM, USA
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Veile A, Martin M, McAllister L, Gurven M. Modernization is associated with intensive breastfeeding patterns in the Bolivian Amazon. Soc Sci Med 2013; 100:148-58. [PMID: 24444850 DOI: 10.1016/j.socscimed.2013.10.034] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2013] [Revised: 10/22/2013] [Accepted: 10/24/2013] [Indexed: 11/16/2022]
Abstract
For many traditional, non-industrialized populations, intensive and prolonged breastfeeding buffers infant health against poverty, poor sanitation, and limited health care. Due to novel influences on local economies, values, and beliefs, the traditional and largely beneficial breastfeeding patterns of such populations may be changing to the detriment of infant health. To assess if and why such changes are occurring in a traditional breastfeeding population, we document breastfeeding patterns in the Bolivian Tsimane, a forager-horticulturalist population in the early stages of modernization. Three predictions are developed and tested to evaluate the general hypothesis that modernizing influences encourage less intensive breastfeeding in the Tsimane: 1) Tsimane mothers in regions of higher infant mortality will practice more intensive BF; 2) Tsimane mothers who are located closer to a local market town will practice more intensive BF; and 3) Older Tsimane mothers will practice more intensive BF. Predictions were tested using a series of maternal interviews (from 2003 to 2011, n = 215) and observations of mother-infant dyads (from 2002 to 2007, n = 133). Tsimane breastfeeding patterns were generally intensive: 72% of mothers reported initiating BF within a few hours of birth, mean (±SD) age of CF introduction was 4.1 ± 2.0 months, and mean (±SD) weaning age was 19.2 ± 7.3 months. There was, however, intra-population variation in several dimensions of breastfeeding (initiation, frequency, duration, and complementary feeding). Contrary to our predictions, breastfeeding was most intensive in the most modernized Tsimane villages, and maternal age was not a significant predictor of breastfeeding patterns. Regional differences accounted for variation in most dimensions of breastfeeding (initiation, frequency, and complementary feeding). Future research should therefore identify constraints on breastfeeding in the less modernized Tsimane regions, and examine the formation of maternal beliefs regarding infant feeding.
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Affiliation(s)
- Amanda Veile
- Department of Anthropology, University of Massachusetts Boston, 100 Morrissey Blvd., Boston, MA 02125-3393, USA.
| | - Melanie Martin
- Integrative Anthropological Sciences Program, Department of Anthropology, University of California-Santa Barbara, Santa Barbara, CA 93106, USA
| | - Lisa McAllister
- Integrative Anthropological Sciences Program, Department of Anthropology, University of California-Santa Barbara, Santa Barbara, CA 93106, USA
| | - Michael Gurven
- Integrative Anthropological Sciences Program, Department of Anthropology, University of California-Santa Barbara, Santa Barbara, CA 93106, USA
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Trumble BC, Cummings DK, O'Connor KA, Holman DJ, Smith EA, Kaplan HS, Gurven MD. Age-independent increases in male salivary testosterone during horticultural activity among Tsimane forager-farmers. EVOL HUM BEHAV 2013; 34. [PMID: 24187482 DOI: 10.1016/j.evolhumbehav.2013.06.002] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Testosterone plays an important role in mediating male reproductive trade-offs in many vertebrate species, augmenting muscle and influencing behavior necessary for male-male competition and mating-effort. Among humans, testosterone may also play a key role in facilitating male provisioning of offspring as muscular and neuromuscular performance are deeply influenced by acute changes in testosterone. This study examines acute changes in salivary testosterone among 63 Tsimane men ranging in age from 16-80 (mean 38.2) years during one-hour bouts of tree-chopping while clearing horticultural plots. The Tsimane forager-horticulturalists living in the Bolivian Amazon experience high energy expenditure associated with food production, have high levels of parasites and pathogens, and display significantly lower baseline salivary testosterone than age-matched US males. Mixed-effects models controlling for BMI and time of specimen collection reveal increased salivary testosterone (p<0.001) equivalent to a 48.6% rise, after one hour of tree chopping. Age had no effect on baseline (p=0.656) or change in testosterone (p=0.530); self-reported illness did not modify testosterone change (p=0.488). A comparison of these results to the relative change in testosterone during a competitive soccer tournament in the same population reveals larger relative changes in testosterone following resource production (tree chopping), compared to competition (soccer). These findings highlight the importance of moving beyond a unidimensional focus on changes in testosterone and male-male aggression to investigate the importance of testosterone-behavior interactions across additional male fitness-related activities. Acutely increased testosterone during muscularly intensive horticultural food production may facilitate male productivity and provisioning.
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Affiliation(s)
- Benjamin C Trumble
- Institute for Social, Behavioral, and Economic Research, University of California Santa Barbara
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Blackwell AD, Martin M, Kaplan H, Gurven M. Antagonism between two intestinal parasites in humans: the importance of co-infection for infection risk and recovery dynamics. Proc Biol Sci 2013; 280:20131671. [PMID: 23986108 DOI: 10.1098/rspb.2013.1671] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Co-infection may affect transmission and recovery from infection, but remains an understudied element of disease ecology, particularly with regard to antagonism between parasites sharing a host. Helminth and giardia infections are often endemic in the same populations and both occupy the small intestine; yet few studies have examined interactions between these parasites. We report on helminth-giardia co-infections in a panel study of forager-horticulturalists in the Bolivian lowlands. Parasites were identified in faecal samples from 3275 participants, collected during 5235 medical exams over 6 years. Longitudinal co-infection patterns were examined using logistic mixed and multi-state Markov models. The most prevalent infections were hookworm (56%), Giardia lamblia (30%) and Ascaris lumbricoides (15%). Cross-sectionally, hookworm and A. lumbricoides were negatively associated with G. lamblia (OR = 0.60; OR = 0.65, respectively). Longitudinally, giardia infection was less likely in helminth-infected individuals (HR: 0.46). Infection with helminths was also less likely for individuals infected with giardia (HR: 0.71). Finally, treatment with mebendazole reduced subsequent hookworm infections, but resulted in a marginal increase in the odds of G. lamblia infection. Our results provide evidence for an antagonistic relationship between helminths and giardia, and suggest that co-infection should be considered in disease transmission models and treatment decisions.
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Affiliation(s)
- Aaron D Blackwell
- Department of Anthropology, University of California, Santa Barbara, CA 93106-3210, USA.
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Stieglitz J, Gurven M, Kaplan H, Winking J. Infidelity, jealousy, and wife abuse among Tsimane forager-farmers: Testing evolutionary hypotheses of marital conflict. EVOL HUM BEHAV 2012; 33:438-448. [PMID: 23459748 DOI: 10.1016/j.evolhumbehav.2011.12.006] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- Jonathan Stieglitz
- Department of Anthropology, University of New Mexico, Albuquerque, NM 87131
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