Browsing by Autor "Michael Gurven"

Now showing 1 - 9 of 9

Do Markets Worsen Economic Inequalities? Kuznets in the Bush
(Springer Science+Business Media, 2004) Ricardo Godoy; Michael Gurven; Elizabeth Byron; Victòria Reyes-García; James Keough; Vincent Vadez; David Wilkie; William R. Leonard; Lilian Apaza; Tomás Huanca
Does Blood Pressure Inevitably Rise With Age?
(Lippincott Williams & Wilkins, 2012) Michael Gurven; Aaron D. Blackwell; Daniel Eid Rodríguez; Jonathan Stieglitz; Hillard Kaplan
The rise in blood pressure with age is a major risk factor for cardiovascular and renal disease, stroke, and type 2 diabetes mellitus. Age-related increases in blood pressure have been observed in almost every population, except among hunter-gatherers, farmers, and pastoralists. Here we tested for age-related increases in blood pressure among Tsimane forager-farmers. We also test whether lifestyle changes associated with modernization lead to higher blood pressure and a greater rate of age-related increase in blood pressure. We measured blood pressure longitudinally on 2248 adults age ≥ 20 years (n=6468 observations over 8 years). Prevalence of hypertension was 3.9% for women and 5.2% for men, although diagnosis of persistent hypertension based on multiple observations reduced prevalence to 2.9% for both sexes. Mixed-effects models revealed systolic, diastolic, and pulse blood pressure increases of 2.86 (P<0.001), 0.95 (P<0.001), and 1.95 mmHg (P<0.001) per decade for women and 0.91 (P<0.001), 0.93 (P<0.001), and -0.02 mmHg (P=0.93) for men, substantially lower than rates found elsewhere. Lifestyle factors, such as smoking and Spanish fluency, had minimal effect on mean blood pressure and no effect on age-related increases in blood pressure. Greater town proximity was associated with a lower age-related increase in pulse pressure. Effects of modernization were, therefore, deemed minimal among Tsimane, in light of their lean physique, active lifestyle, and protective diet.
Female intrasexual competition and reputational effects on attractiveness among the Tsimane of Bolivia
(Elsevier BV, 2005) Stacey L. Rucas; Michael Gurven; Hillard Kaplan; Jeffrey Winking; Steven W. Gangestad; María Crespo
Health costs of reproduction are minimal despite high fertility, mortality and subsistence lifestyle
(Nature Portfolio, 2016) Michael Gurven; Megan Costa; Benjamin C. Trumble; Jonathan Stieglitz; Bret Beheim; Daniel Eid Rodríguez; Paul L. Hooper; Hillard Kaplan
Indirect genetic effects among neighbors promote cooperation and accelerate adaptation in a small-scale human society
(American Association for the Advancement of Science, 2025) Jordan S. Martin; Bret Beheim; Michael Gurven; Hillard Kaplan; Jonathan Stieglitz; Benjamin C. Trumble; Paul L. Hooper; Daniel K. Cummings; Daniel Eid Rodríguez; Adrian V. Jaeggi
Explaining the rapid evolution of human cooperation and its role in our species' biodemographic success remains a major evolutionary puzzle. To address this challenge, we tested a social drive hypothesis, which predicts that social plasticity and social selection in human groups cause indirect genetic effects that accelerate the adaptation of fitness, promoting population growth via feedback between the environmental causes and evolutionary consequences of cooperation. Using Bayesian multilevel models to analyze fertility data from a small-scale society, we demonstrate that density- and frequency-dependent indirect genetic effects on fitness promote the evolution of cooperation among neighboring women, increasing the rate of contemporary adaptation by ~5×. Our results show how interactions between the genetic and socioecological processes shaping cooperation in reproduction can drive rapid growth and social evolution in human populations.
Inflammation and Infection Do Not Promote Arterial Aging and Cardiovascular Disease Risk Factors among Lean Horticulturalists
(Public Library of Science, 2009) Michael Gurven; Hillard Kaplan; Jeffrey Winking; Daniel Eid Rodríguez; Sarinnapha M. Vasunilashorn; Jung Ki Kim; Caleb E. Finch; Eileen M. Crimmins
Inflammation may not always be a risk factor for arterial degeneration and CVD, but instead may be offset by other factors: healthy metabolism, active lifestyle, favorable body mass, lean diet, low blood lipids and cardiorespiratory health. Other possibilities, including genetic susceptibility and the role of helminth infections, are discussed. The absence of PAD and CVD among Tsimane parallels anecdotal reports from other small-scale subsistence populations and suggests that chronic vascular disease had little impact on adult mortality throughout most of human evolutionary history.
Mortality experience of Tsimane Amerindians of Bolivia: Regional variation and temporal trends
(Wiley, 2007) Michael Gurven; Hillard Kaplan; Alfredo Zelada Supa
This paper examines regional and temporal trends in mortality patterns among the Tsimane, a population of small-scale forager-horticulturalists in lowland Bolivia. We compare age-specific mortality in remote forest and riverine regions with that in more acculturated villages and examine mortality changes among all age groups over the past 50 years. Discrete-time logistic regression is used to examine impacts of region, period, sex, and age on mortality hazard. Villages in the remote forest and riverine regions show 2-4 times higher mortality rates from infancy until middle adulthood than in the acculturated region. While there was little change in mortality for most of the life course over the period 1950-1989, overall life expectancy at birth improved by 10 years from 45 to 53 after 1990. In both periods, over half of all deaths were due to infectious disease, especially respiratory and gastrointestinal infections. Accidents and violence accounted for a quarter of all deaths. Unlike typical patterns described by epidemiologic transition theory, we find a much larger period reduction of death rates during middle and late adulthood than during infancy or childhood. In the remote villages, infant death rates changed little, whereas death rates among older adults decreased sharply. We hypothesize that this pattern is due to a combination of differential access to medical interventions, a continued lack of public health infrastructure and Tsimane cultural beliefs concerning sickness and dying.
Rapidly declining body temperature in a tropical human population
(American Association for the Advancement of Science, 2020) Michael Gurven; Thomas S. Kraft; Sarah Alami; Juan Copajira Adrian; Edhitt Cortez Linares; Daniel K. Cummings; Daniel Eid Rodríguez; Paul L. Hooper; Adrian V. Jaeggi; Raúl Quispe Gutierrez
Normal human body temperature (BT) has long been considered to be 37.0°C. Yet, BTs have declined over the past two centuries in the United States, coinciding with reductions in infection and increasing life expectancy. The generality of and reasons behind this phenomenon have not yet been well studied. Here, we show that Bolivian forager-farmers (n = 17,958 observations of 5481 adults age 15+ years) inhabiting a pathogen-rich environment exhibited higher BT when first examined in the early 21st century (~37.0°C). BT subsequently declined by ~0.05°C/year over 16 years of socioeconomic and epidemiological change to ~36.5°C by 2018. As predicted, infections and other lifestyle factors explain variation in BT, but these factors do not account for the temporal declines. Changes in physical activity, body composition, antibiotic usage, and thermal environment are potential causes of the temporal decline.
Subjective well-being across the life course among non-industrialized populations
(American Association for the Advancement of Science, 2024) Michael Gurven; Yoann Buoro; Daniel Eid Rodríguez; M. Katherine Sayre; Benjamin C. Trumble; Aili Pyhälä; Hillard Kaplan; Arild Angelsen; Jonathan Stieglitz; Victòria Reyes-García
Subjective well-being (SWB) is often described as being U-shaped over adulthood, declining to a midlife slump and then improving thereafter. Improved SWB in later adulthood has been considered a paradox given age-related declines in health and social losses. While SWB has mostly been studied in high-income countries, it remains largely unexplored in rural subsistence populations lacking formal institutions that reliably promote social welfare. Here, we evaluate the age profile of SWB among three small-scale subsistence societies (n = 468; study 1), forest users from 23 low-income countries (n = 6987; study 2), and Tsimane' horticulturalists (n = 1872; study 3). Across multiple specifications, we find variability in SWB age profiles. In some cases, we find no age-related differences in SWB or even inverted U-shapes. Adjusting for confounders reduces observed age effects. Our findings highlight variability in average well-being trajectories over the life course. Ensuring successful aging will require a greater focus on cultural and socioecological determinants of individual trajectories.