EPISODE 19 / Sep 16, 2025
Audio from the publisher. Timestamps reference the archived recording.
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In this episode of the podcast, hosts Dave Pietraszewski and David Pinsof are joined by anthropology professor Mike Gurven from UC Santa Barbara to discuss human longevity, life history, and his upcoming book, Seven Decades. Gurven challenges common misconceptions about ancestral lifespans, arguing that human biology is evolutionarily designed to span about seventy years, and examines how non-industrial populations like the Tsimane in Bolivia maintain exceptional cardiovascular health through high levels of physical activity. The conversation also explores the evolutionary roots of aging, productivity in later life, demographic transitions in fertility, and how socioecological niche diversity shapes personality structures across different societies.
QUESTIONS TO KEEP IN MIND
Dave Pietraszewski and David Pinsof introduce the podcast, welcome anthropology professor Mike Gurven from UC Santa Barbara, and discuss academic departmental structures and the upcoming release of Gurven's new book, Seven Decades.
Dave and David welcome Mike Gurven to discuss his research on lifespan, life history, and human development.
“today we're gonna talk to Mike Gervin. And Mike Irvin, uh, what he studies” 1:54
Mike Gurven explains the premise of his book Seven Decades, arguing that the human body is evolved to last around seventy years, and addresses the common misconception that our ancestors routinely died by age thirty-five.
Gurven explains that our species-typical body is built to last about seven decades, distinguishing evolutionary potential from average lifespan.
“our species typical kind of body is kind of built to last about seven decades.” 8:43
High early-life mortality and high fertility in ancestral populations created triangular population pyramids, contributing to the false idea that people did not live past thirty-five.
“because it's not just the fact that uh it's not just thinking about human survival, but it is also thinking about fertility” 10:25
Host Dave Pietraszewski, David Pinsof, and guest Mike Gurven discuss the evolutionary history of human longevity, challenging the notion that old age is exclusively a modern problem. They explore how life stages, including middle and older age, are evolved species-typical designs that offer untapped potential rather than being mere burdens or periods of decay.
Gurven argues that having middle-age and older age life stages has always been part of our species typical design and contributes to human success.
“part of the reason for our species success is having middle-age and older age life stages” 13:23
Pinsof relates Gurven's points to the evolutionary design of lifespan stages, similar to biological transformations in other organisms.
“in the same way, there can be design for stages of the life.” 14:50
Mike Gurven explains his motivation for writing a book on aging that synthesizes broader evolutionary insights rather than offering quick health hacks or molecular biology tips. The speakers examine how studying non-industrial and hunter-gatherer populations provides crucial context on aging, heart disease, and physiological health that standard Western medicine often overlooks.
Gurven discusses how examining mummies across different ancient populations reveals historical evidence of arterial calcification and questions about atherosclerosis.
“cardiologists and radiologists who who, you know, anything they can get their hands on” 21:48
Guest Mike Gurven discusses with hosts Dave Pietraszewski and David Pinsof how researchers investigated cardiovascular health in the Tsimane population of Bolivia. Using blood pressure measures, ankle-brachial indexes, and CT scans, they discovered a remarkably low prevalence of subclinical atherosclerosis and coronary artery calcification compared to industrialized populations.
85% of people had absolutely no calcification in their coronary arteries
“85% of people had absolutely no calcification in their” 27:15
The hosts and Mike Gurven explore the lifestyle factors behind the Tsimane and Moseten populations' low rates of heart disease. They examine the role of continuous light-to-moderate physical activity, daily step counts, and the potential impacts of modernization and new labor-saving technologies.
physical activity definitely seems to be kind of central to all aspects of their lifestyle
“physical activity definitely seems to be kind of central to all” 34:27
the Chamana tend to get about 17,000 steps a day
“the Chamana tend to get about 17,000 steps a day.” 35:57
Dave Pietraszewski, David Pinsof, and guest Mike Gurven discuss how built environments, urban planning, and walkable communities impact physical activity, health, and cardiovascular wellness. They contrast US car culture with European cities and examine the public health benefits of making active, healthy choices easier at the population level.
structure our communities in ways that the easier option is the healthier option
“structure our communities in ways that the easier option is the healthier option.” 39:29
it's almost an urban planning issue for our health
“it's almost an urban planning issue for uh our health, right?” 41:33
Mike Gurven, Dave Pietraszewski, and David Pinsof explore the quality versus quantity of life, examining how formal retirement is a modern invention compared to traditional hunter-gatherer societies. They discuss how older adults continue making valuable economic, social, and familial contributions, and how psychological well-being is tied to being a net contributor rather than a burden.
there's no such thing as retirement, right? That's something that was like literally, you know, invented
“there's no such thing as retirement, right? That's something that was like literally, you know, invented” 43:26
if you're in a position where you're kind of a net giver... you're way happier
“If you're in a position where you're kind of a net giver, net your your net transfers to people is positive, you're way happier with your life” 47:39
Dave Pietraszewski, David Pinsof, and guest Mike Gurven discuss the concept of retirement and how human evolutionary history shapes our psychological desire to remain socially relevant, productive, and avoid being a burden. They examine whether modern economic and cultural structures make older adults obsolete compared to small-scale foraging societies.
we evolved to not want to be a burden on others
“we evolved to not want to be a burden on others” 51:13
Mike Gurven responds to the pessimistic take on elder obsolescence by comparing modern attitudes with ethnographic data from hunter-gatherer societies. The speakers differentiate between the young-old and very elderly, discussing how contributions continue across different life stages despite rapid technological and cultural shifts.
in almost every society, you see some elements of yeah, respect and honor for the elderly
“in almost every society, you see some elements of yeah, respect and honor for the elderly” 55:25
a little bit of wisdom and experience are just very valuable
“a little bit of wisdom and experience are just very valuable” 1:00:01
Dave Pietraszewski, David Pinsof, and guest Mike Gurven discuss creative community solutions that leverage the wisdom and experience of older adults through mentorship and cooperative programs. The speakers address concerns about moral hazard and free riding, emphasizing that people generally want to feel like contributing members of society when given accessible opportunities and proper coordination.
The speakers discuss how partnering older adults with younger people through mentorship programs can simultaneously reduce loneliness and improve community outcomes like literacy and crime prevention.
“increasing activity towards even just like mentorship programs and and things that, you know, trying to kill two birds, one stone.” 1:01:40
The hosts and guest examine the common assumption that people will inherently free ride if given assistance, arguing instead that individuals genuinely want to contribute value.
“people will just free ride the hell out of things, and it's actually human nature.” 1:04:27
David Pinsof and guest Mike Gurven explore the demographic transition puzzle where modern wealth and abundance correlate with declining fertility rates rather than a population boom. They examine how human capital investment, delayed reproduction, and perceived economic requirements influence family size from an evolutionary and life history perspective.
The speakers highlight the historical anomaly of having multiple generations coexisting simultaneously due to changing population structures and lower fertility.
“probably never before in history have we had this many generations sort of coexistent” 1:08:04
Gurven discusses how the modern accumulation of human capital in the brain delays the shift from growth to reproduction compared to ancestral patterns.
“if that's happening at age 30, right, that's clearly beyond just somatic growth. That's you know, all that human capital in our brain” 1:09:52
Dave Pietraszewski, David Pinsof, and guest Mike Gurven discuss the psychological and economic costs of raising children in modern, isolated societies compared to small-scale traditional societies like the Ache and Tsimane, examining how perceived resource requirements and status aspirations influence fertility decisions.
it definitely adds to the the costs of raising children
“it definitely adds to the the costs of raising children” 1:12:36
you really get the sense that someone who's worthwhile, competent, has status, should have a family and have a big family
“you really get the sense that someone who's worthwhile, competent, has status, should have a family and have a big family” 1:14:35
The speakers explore how status as a positional good drives luxury expenditures and investment in children's competitiveness. They also examine how structural factors, such as parental leave and childcare policies, impact fertility rates and how evolutionary psychology intersects with economic and social environments.
since status is such a positional good, right, it's always changing
“since status is such a positional good, right, it's always changing” 1:19:08
many of the people who are against that are also the people who are super concerned about like plummeting fertility rates
“many of the people who are against that are also the people who are super concerned about like plummeting fertility rates” 1:22:02
Mike Gurven discusses his initial exploration into measuring personality among the Tsimane, explaining how standard Big Five personality inventories did not neatly map onto small-scale forager societies. Gurven and Dave Pietraszewski explore how behavioral ecology and translation challenges shaped their methodological approach to capturing individual differences.
it's it's um someone a colleague once made a joke about they think I have like a a gr the same graph in every paper
“someone a colleague once made a joke about they think I have like a a gr the same graph in every paper” 1:25:08
as soon as you find something that's not big five, it's it's go straight for the methodological jugular
“as soon as you find something that's not big five, it's it's go straight for the methodological jugular” 1:29:50
Mike Gurven explains that Tsimane personality structure resembles a constrained 'big two' rather than independent Big Five factors, comparing it to an equalizer with linked bands. The speakers examine how modern socioecological complexity, diverse economic niches, and job variety expand personality differences compared to small-scale societies.
what we called it loosely like a big two that seemed to be like there's such industriousness and like pro-sociality seem to be kind of two dimensions
“what we called it loosely like a big two that seemed to be like there's such industriousness and like pro-sociality” 1:31:19
if there's many more different ways to make a living, then sort of like in the old ecological theory, you know, individuals will sort of like fill up that niche space
“if there's many more different ways to make a living, then sort of like in the old ecological theory” 1:34:25
Guest Mike Gurven and the hosts discuss how personality structure varies in relation to niche diversity, comparing modern urbanization and streaming media subcultures to ancestral environments. Gurven explains empirical findings on personality correlation structures and developmental inputs.
the overall correlation varies. And it varies in a way in relation to the niche diversity
“the overall correlation varies. And it varies in a way in relation to the niche diversity” 1:36:45
urbanization, it's sort of like this proxy for this like flowering of all these like niches
“urbanization, it's sort of like this proxy for this like flowering of all these like niches” 1:42:00
As the interview concludes, the hosts ask Mike Gurven what topics were left unaddressed. Gurven discusses the future of evolutionary social science, the changing dynamics of small-scale societies, and how researchers should study ongoing cultural and demographic shifts rather than hiding them.
as groups are kind of going under various degrees of changes on all fronts, you know, I feel like it's like a it's a laboratory
“as groups are kind of going under various degrees of changes on all fronts, you know, I feel like it's like a it's a laboratory” 1:45:39
Dave Pietraszewski and David Pinsof talk with guest Mike Gurven about human behavioral ecology, his published work, and details on how listeners can purchase his upcoming book through Amazon, Target, or the Princeton University Press website using a discount code. They conclude the interview by discussing the importance of science communication.
Mike talked about like 12 papers that didn't see the light of day, and that sounds like a lot
“Mike talked about like 12 papers that didn't see the light of day” 1:48:47
Hosts Dave Pietraszewski and David Pinsof reflect on finishing another episode, praise their guest selection process, ask listeners for reviews and support on Patreon, and playfully brainstorm unconventional future interview formats.
A passage from this discussion.
“Well, David, um I I start uh let's start over.” 1:50:50
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