Act More Like the Hunter-Gatherers We Evolved to be by Focusing on these Four Areas
By: Alex Goik
Tags: Evolutionary Biology, Evolution, Health, Personal Development, The Ascent

Act More Like the Hunter-Gatherers We Evolved to be by Focusing on these Four Areas

No, I’m not about to suggest that we start sharpening our spears

“Group hikers atop a rocky cliff taking a break by watching the sunset at Joshua Tree” by Cynthia Magana on Unsplash

Something that acclaimed Harvard historian Yuval Noah Harrari’s book ‘Sapiens’ cemented in my mind is the minuscule time-frame that homo-sapiens have spent living within agrarian societies.

For the vast, vast amount of time that our species’ has trodden the evolutionary road from ape to modern human, we adapted to living the lifestyle of the humble hunter-gatherer. The prehistoric transition to settled agriculture that occurred some 11,000–12,00 years ago is far surpassed by the near 200,000 years that we spent living in small, nomadic tribal communities. As a result of our unique evolutionary biology, we have innate needs that are seldom seen satisfied in modern society.

Now I am not about to suggest that we each head to our nearest archery range and start practicing for our return to the forest — I’ll be the first to admit that I’m a bad shot. Instead, what I’m advocating is for people to consider the disruptive impact that life in modern society can have on an animal that evolved under very different circumstances.

So what does living like a modern hunter-gatherer entail?

Nutrition and Fasting

Living like a hunter-gatherer means eating a varied and seasonal diet comprised of whole-grown, unprocessed foods — punctuated by periods of no eating at all.

Having a McDonald’s on every street corner has made us forget that the notion of eating three meals a day is a modern construct. For the large amount of time that we spent living as hunter-gatherers, our relationship with food was characterized by a dynamic of feast and famine.

The days your tribe spent gorging on the meat from a downed animal were matched if not exceeded by those where the arrow missed its mark, the last wild berries were spoiled from frost, or a group of competitors moved into the area beating you to the spoils.

As a result of this dynamic we have particular responsive mechanisms built into our biological hardware that only become active during periods of nutritional deprivation.

For example, the body’s process of ‘autophagy’ — what can be conceived of as programmed cell-death — kicks into gear when we are exposed to short stints of starvation. While sounding somewhat ominous, autophagy in mammals has been proven to enhance the immune system by eliminating intracellular pathogens, recycle damaged proteins, organelles and aggregates, and encourage the growth of brain and nerve cells among a host of other benefits.

In recent years a variety of movements, diets and lifestyles have accompanied the growing interest into ancestral diets and the dynamics of fasting. Two examples are the ‘ancestral eating’ movement and the ‘primal blueprint’ lifestyle program. Both advocate simplifying our dietary choices, selecting natural ingredients and cutting out excessive carbs and grains, processed foods and hydrogenated oils.

On the issue of how to best incorporate fasting into your lifestyle, I’m not advising that you forgo food immediately. There are methods to fasting supported by a growing body of scientific literature that can help guide you in the right direction. The research conducted by Dr Satchin Panda of the Salk Institute for Biological Studies into the benefits of time-restricted eating and Dr Valter Longo’s work on the fasting-mimicking diet are two good places to start.

Energy Expenditure

I’ve chosen this subtitle because I am not just talking about exercise. Now more so than ever before can humans get away with doing less. Less movement, less physical activity, less exertion. It has been proven that on average hunter-gatherers had higher levels of physical activity than people residing in modern market-economies. However, while it may be tempting to reduce the obesity epidemic and other health issues to a simple argument about our reduction in overall energy expenditure, the real story is somewhat more complex.

A study published in 2015 examined the daily energy expenditure of the Hadza hunter-gatherers located in Northern Tanzania and compared this to individuals living in modern market-economies. The Hadza are one of the remaining hunter-gatherers groups surviving today, known for their traditional foraging lifestyle in the savannah-woodland environment. While no living population is a perfect model of our species’ past, the Hadza lifestyle is considered similar in critical ways to that of our ancestors of 10,000 years ago.

Contrary to popular expectations, it was found that while the Hadza engaged in more physical activity per day than their estern counterparts — males walked on average 11.4km and women 5.8km — when researchers controlled for body size, there was no difference in the average daily energy expenditure between the Hadza and modern market-economy groups.

The result led researches to posit that “adults with high levels of physical activity may adapt by reducing energy allocation to other physical activity”. Such findings suggest that there is likely more behind the obesity epidemic than the relative decline in our levels of physical exercise.

This being the case, we must distance ourselves from the antiquated notion that health simply equals a low body fat percentage. In recent years we’ve seen multiple studies examine the negative impact that living a sedentary lifestyle can have on our overall levels of health and longevity.

A 2017 study published in the Annals of Internal Medicine demonstrated how uninterrupted bouts of sedentary time can be directly associated with increases in all-cause mortality. The study used hip-mounted activity monitors to objectively measure inactivity during waking time over a period of seven days in 8,000 adults over age 45. The researchers found that adults who sit for one to two hours at a time without moving have a higher mortality rate than those who accrue the same amount of sedentary time in shorter bouts.

Therefore, in addition to prescribed bouts of moderate to strenuous physical exercise, we must also factor the need for continuous movement throughout the day — characteristic of our hunter-gatherer ancestry — into our health paradigms.

Sleep and Light exposure

Modern society is a society devoid of darkness. The discovery of electricity has resulted in momentous leaps in human ingenuity and brought with it comfort, convenience and safety. Benefits aside, our constant exposure to light also has serious consequences for a species that evolved adhering to a strict cycle of night and day.

The bodies ‘Circadian Rhythm’ — the biological clock that regulates our sleep-wake cycles, hormone release, digestion, body temperature, and other important bodily functions — has a natural oscillation of 24 hours. Duration and quality of sleep are both optimized when the sleep period is appropriately aligned with the timing of the circadian body clock.

With the availability of electric illumination however, sleep patterns have been substantially altered. A growing body of research has appeared over the past quarter century documenting the adverse consequences of short-term, total or partial sleep deprivation on human learning, mood, behavior, performance, and organ-system function. As early as 1993 a report from the National Commission on Sleep Disorders Research estimated that total sleep time for the US population had decreased by 20% over the past century.

These trends have since only been exacerbated by the onset of handheld electrical devices that we take with us wherever we go — including the bedroom. The blue light we subject ourselves to when we use our iPhone or computer at night disrupts the bodies internal clock and can jeopardise our natural sleep-wake patterns.

A 2015 study that appeared in Current Biology examined sleep behaviors in three genetically and geographically separated societies: the Hadza who we’ve met, the San from Namibia, and Tsimané from Bolivia. Interestingly the study found that sleep durations in these groups were between 5.7–7.1 hours — amounts near the low end of those living in industrial societies.

Although periods of sleep duration were not shown to vary greatly between hunter-gatherer groups and those of industrialized societies, what the study did reveal was that none of the former ever complained about having trouble sleeping. Upon probing further the researchers found that the concept of ‘insomnia’ is non-existent in each of these groups respective languages. This finding is in stark contrast with the 10–30% of individuals living in industrialized society that struggle to initiate or maintain sleep.

In line with what we know about the bodies Circadian Rhythm, it was found that for these non-industrial groups, sleep onset typically occurred several hours after sunset — on average 3.3 hours — and awakening usually just before sunrise. Researchers attributed awakening times to changes in ambient temperature rather than early levels of light exposure. This suggests that natural changes in temperature may also be an important factor in controlling sleep behaviour, but one that is largely mitigated by temperature control in many modern homes.

The result of the study led researchers to conclude that:

“Mimicking aspects of the natural environment might be effective in treating certain modern sleep disorders”.

Therefore, instead of battling our internal clocks, we should try to find ways to accommodate natural sleep-wake pattern variation as our hunter-gatherer ancestors adapted to doing.

Community and Tribe

So far we have touched on the tangible differences in lifestyle between hunter-gatherer and modern industrialized societies. However, for a complete analysis we must also consider social and relationship factors.

As hunter-gatherers we evolved to live in cooperative, tight-knit communities which were prosocial and in which individuals experienced constant companionship. As a result, we each have particular social-emotional needs derived from tribal dynamics. Not getting these fulfilled can leave us feeling disconnected, confused and isolated.

Bestselling author Sebastian Junger in his book ‘Tribe: On Homecoming and Belonging’ explores this dynamic through the lens of returned US army veterans. Junger demonstrates how ancient tribal behaviors of loyalty, inter-reliance and cooperation are typified within modern soldiering groups. He argues that the struggles veterans face reintegrating when they return home do not stem entirely from the trauma they’ve suffered, but also from the individualist societies they must reintegrate into.

Such an observation is reinforced by recent studies (such as this one on loneliness and this one on depression in the US) that show how a growing proportion of people are suffering from clinical depression, anxiety and chronic loneliness.

In our modern society, it is therefore important that we each seek out and satisfy our innate need to be valued as members of a tribe. Thankfully this tribal dynamic can be derived from a variety of sources. Nurturing hospitable familial relations, participating in team sports, clubs or community groups are all good places to start.

Conclusion

Understanding our common evolutionary biology is key to living a good life in the 21st century — but as an area of focus it is frequently overlooked. Humans have innate needs pertaining to nutrition, physical exercise, sleep and community that have remained with us despite the fact that many of us now reside in urban instead of wooded jungle. Figuring out how to best satisfy these needs is crucial if we are to improve ourselves and our relationships with others.

Alex Goik commonly writes for Mogul News and at Foreign Affairs Navigator where he strives to offer fresh perspectives on foreign affairs, tech and China (coupled with the odd analysis of human nature).