Nov 1st 2018

Hunter-gatherers live nearly as long as we do but with limited access to healthcare

by Vybarr Cregan-Reid

Reader in Environmental Humanities and Author of 'Footnotes: How running makes us human', University of Kent

 

Modern life has many benefits. Transport, comfy furniture, smartphones, TV, the internet, dentistry and advanced medicine would be at the top of most people’s lists. Our bodies also show signs of responding positively to modern life. In almost every part of the world, we are much taller than we used to be. We also live much longer, with life expectancy inching towards 80 in many wealthy countries, while everyone “knows” ancient humans usually died in their twenties. But what I discovered while researching my book, is that things are more complex than that.

Being taller may be linked to higher social status and statistically linked with higher earnings (meaning easier access to healthcare), but a variety of papers show that being shorter has advantages when it comes to longevity. As urban populations grow quickly in height (Europeans have grown about five inches in the last two centuries), the effect on lifespan is unlikely to be wholly positive.

The other claim is that we live much longer than we used to. If life expectancy in ancient Greece and Rome was anything to go by, then early city life was brutal, killing off its inhabitants by about the age of 30. All the diseases that occur in environments with poor sanitation or where large numbers of people live in close proximity, thrived in those cities. If we are to compare ourselves to those early city dwellers, then our life expectancy is undeniably much greater.

As a species, though, we have not been living in cities for very long at all. If you were to compress the lifespan of hominid species (2.3m years) into a nine-to-five working day, then cities don’t arrive until after 4:59 pm. Except for the few thousand years of agriculture that preceded those big cities, the rest of our time on Earth has been spent hunting and gathering.

Life expectancy for early humans varied hugely but was in the region of 25 years. This is the single most common reason for rejecting ideas that look at previous incarnations of humanity for guidance on, for example, how we might live healthier, longer lives today.

Out on the savannah, early humans were regularly exposed to danger. The world was changing quickly and drought or famine could strike at any moment. But despite their life expectancy, it’s unlikely that a significant number of early humans died in their twenties. While the threats from violent encounters with predators, prey or other tribes were significant, 25 as a number is utterly misleading.

The problem is in the maths. When people talk of life expectancy in hunter-gatherers, what they are really talking about is “life expectancy at birth”.

Confusing stats

Today in the UK and the US infant mortality rates are well below 1%, so to speak of an average (or mean) age of death makes perfect sense. Those numbers really do tell us how long, on average, the people in that community live. For hunter-gatherer communities, we need a different mathematical model because, without healthcare, infant mortality rates could be in the region of 20-40%.

If nearly half a group dies in infancy and the other half live well into their early fifties that yields a mean life expectancy of 25: misleading and not in the least helpful for telling us about how long people live for.

In hunter-gatherer groups, life was, and is, undeniably hard, but their lifespan was not as short as the numbers press us to think. If you were a hunter-gatherer and you made it to adolescence, there was a strong likelihood that you would live a long and healthy life – not so different from modern humans.

The Tsimané, for example, are an indigenous forager people of lowland Bolivia and their modal lifespan is 70 years (“modal” being the number that appears with the greatest frequency in a given dataset). People in wealthier countries, with advanced healthcare and better diets, do live longer. But instead of the 50 years difference we hear bandied about, it is just a few years.

Firefighting

Everyone knows that neither group is experiencing optimum conditions for longevity. The top ten causes of death in wealthy countries are dominated by metabolic disorders and cancers. Nearly all of which have strong associations with the lower levels of physical activity in these countries. The multibillion pound healthcare industry that supports modern lifestyles only buys people in wealthy countries a few extra years.

Modern life does have many benefits, but when it persuades us to use transport, sit in a chair at work, or watch TV for extended periods, we increasingly have to turn to medicine for solutions because these habits are killing hundreds of millions of us each year.

With 70% of people in the US on prescription drugs (50% in the UK), it seems that as lifespan inches upwards, disease is skyrocketing. The irony is that many advances in modern medicine are firefighting those very problems that modern life itself has created.

 

Vybarr Cregan-Reid, Reader in Environmental Humanities, University of Kent

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Browse articles by author

More Essays

May 1st 2021
EXTRACT: " The sad reality is that the Mizrahim (Jews of Middle Eastern and North African descent) were discriminated against from the day of Israel’s inception, whose Ashkenazi (European Jewish) leaders viewed them as intellectually inferior, “backward,” and “too Arab,” and treated them as such, largely because the Ashkenazim agenda was to maintain their upper-class status while controlling the levers of power, which remain prevalent to this day." ..... " The greatest heartbreaking outcome is that for yet another generation of Israelis, growing up in these debilitating conditions has a direct effect on their cognitive development. A 2015 study published in Nature Neuroscience found that “family income is significantly correlated with children’s brain size…increases in income were associated with the greatest increases in brain surface area among the poorest children.” "
Apr 25th 2021
EXTRACT: "We all owe Farah Nabulsi an enormous debt of gratitude. In a short 24-minute film, The Present, she has exposed the oppressive indecency of the Israeli occupation while telling the deeply moving story of a Palestinian family. What is especially exciting is that after winning awards at a number of international film festivals​, Ms. Nabulsi has been nominated for an Academy Award for this remarkable work of art. " 
Apr 25th 2021
EXTRACT: "When I crashed to the floor of my home in Bordeaux recently after two months of Covid-19 dizziness, I was annoyed. The next day I collapsed again. Now I was worried. What I didn’t know was that my brain was sloshing around inside my skull, causing a mild concussion. Nor did I know that I was in for a whole new world of weird and wonderful hallucinations."
Apr 13th 2021
EXTRACT: "Overall, our review has found that there isn’t evidence to back up the claims that veganism is good for your heart. But that is partly because there are few studies ....... But veganism may have other health benefits. Vegans have been found to have a healthier weight and lower blood glucose levels than those who consume meat and dairy. They are also less likely to develop cancer, high blood pressure and diabetes. "
Apr 8th 2021
EXTRACT: "Pollock’s universe, the universe of Mural, cannot be said to be a rational universe. Nor is it simply devoid of all sense. It is not a purely imaginary world, although in it everything is in a constant state of flux. Mural invokes one of the oldest questions of philosophy, a question going back to the Pre-Socratic philosophers Parmenides and Heraclitus – namely, whether the nature of Reality constitutes unchanging permanence or constant movement and flux. For Pollock, the only thing that is truly unchanging is change itself. The only certainty is that all is uncertain."
Apr 8th 2021
EXTRACT: "Many present day politicians appear to have psychopathic and narcissistic traits too. It’s easy to spot such leaders, because they are always authoritarian, following hardline policies. They try to subvert democracy, to reduce the freedom of the press and clamp down on dissent. They are obsessed with national prestige, and often persecute minority groups. And they are always corrupt and lacking in moral principles."
Apr 6th 2021
EXTRACT: "This has led some to claim that not just half, but perhaps nearly all advertising money is wasted, at least online. There are similar results outside of commerce. One review of field experiments in political campaigning argued “the best estimate of the effects of campaign contact and advertising on Americans’ candidates choices in general elections is zero”. Zero!"
Mar 30th 2021
EXTRACT: "The Father is an extraordinary film, from Florian Zeller’s 2012 play entitled Le Père and directed by Zeller. I’m here to tell you why it is a ‘must see’." EDITOR'S NOTE: The official trailer is attached to the review.
Mar 28th 2021
EXTRACT: "Picasso was 26 in 1907, when he completed the Demoiselles; de Kooning was 48 in 1952, when he finished Woman I.  The difference in their ages was not an accident, for studies of hundreds of painters have revealed a striking regularity - the conceptual painters who preconceive their paintings, from Raphael to Warhol, consistently make their greatest contributions earlier in their careers than experimental painters, from Rembrandt to Pollock, who paint directly, without preparatory studies."
Mar 26th 2021
EXTRACT: "Mental toughness levels are influenced by many different factors. While genetics are partly responsible, a person’s environment is also relevant. For example, both positive experiences while you’re young and mental toughness training programmes have been found to make people mentally tougher."
Mar 20th 2021

The city of Homs has been ravaged by war, leaving millions of people homeless an

Mar 20th 2021
EXTRACT: "There are two main rival models of ethics: one is based on rights, the other on duties. The rights-based model, which traces its philosophical origins to the work of John Locke in the 17th century, starts from the assumption that individuals have rights ....... According to this approach, duties are related to rights, but only in a subordinate role. My right to health implies a duty on my country to provide some healthcare services, to the best of its abilities. This is arguably the dominant interpretation when philosophers talk about rights, including human rights." ........ "Your right to get sick, or to risk getting sick, could imply a duty on others to look after you during your illness." ..... "The pre-eminence of rights in our moral compass has vindicated unacceptable levels of selfishness. It is imperative to undertake a fundamental duty not to get sick, and to do everything in our means to avoid causing others to get sick. Morally speaking, duties should come first and should not be subordinated to rights." ..... "Putting duties before rights is not a new, revolutionary idea. In fact it is one of the oldest rules in the book of ethics. Primum non nocere, or first do no harm, is the core principle in the Hippocratic Oath historically taken by doctors, widely attributed to the ancient Greek philosopher and physician Hippocrates. It is also a fundamental principle in the moral philosophy of the Roman statesman Marcus Tullius Cicero, who in De Officiis (On Duties) argues that the first task of justice is to prevent men and women from causing harm to others."
Mar 18th 2021
EXTRACT: "Several studies have recently compared the difference between antibodies produced straight after a coronavirus infection and those that can be detected six months later. The findings have been both impressive and reassuring. Although there are fewer coronavirus-specific antibodies detectable in the blood six months after infection, the antibodies that remain have undergone significant changes. …….. the “mature” antibodies were better at recognising the variants."
Mar 15th 2021
EXTRACT: "Like Shakespeare, Goya sees evil as something existing in itself – indeed, the horror of evil arises precisely from its excess. It overflows and refuses to be contained by or integrated into our categories of reason or comprehension. By its very nature, evil refuses to remain within prescribed bounds – to remain fixed, say, within an economy where evil is counterbalanced by good. Evil is always excess of evil." ....... "Nowhere is this more evident than in war. Goya offers us a profound and sustained meditation on the nature of war ........ The image of a Napoleonic soldier gazing indifferently on a man who has been summarily hanged, probably by his own belt, expresses the tragedy of war – its dehumanization of both war’s victims and victors."
Mar 14th 2021
EXTRACT: "A blockchain company has bought a piece of Banksy artwork and burnt it. But instead of destroying the value of the art, they claim to have made it more valuable, because it was sold as a piece of blockchain art. The company behind the stunt, called Injective Protocol, bought the screen print from a New York gallery. They then live-streamed its burning on the Twitter account BurntBanksy. But why would anyone buy a piece of art just to burn it? Understanding the answer requires us to delve into the tricky world of blockchain or “NFT” art."
Mar 14th 2021
EXTRACT: "Exercise is good for your health at every age – and you can reap the benefits no matter how late in life you start. But our latest research has shown another benefit of being physically active throughout life. We found that in the US, people who were more physically active as teenagers and throughout adulthood had lower healthcare costs."
Mar 10th 2021
EXTRACT: "Although around one in 14 people over 65 have Alzheimer’s disease, there’s still no cure, and no way to prevent the disease from progressing. But a recent study may bring us one step closer to preventing Alzheimer’s. The trial, which was conducted on animals, has found a specific molecule can prevent the buildup of a toxic protein known to cause Alzheimer’s in the brain."
Feb 24th 2021
EXTRACT: "The art historian George Kubler observed that scholars in the humanities “pretend to despise measurement because of its ‘scientific’ nature.” As if to illustrate his point Robert Storr, former dean of Yale’s School of Art, declared that artistic success is “completely unquantifiable.” In fact, however, artistic success can be quantified, in several ways. One of these is based on the analysis of texts produced by art scholars, and this measure can give us a systematic understanding of how changes in recent art have produced changes in the canon of art history."
Feb 24th 2021
EXTRACT: "The most politically sensitive option we looked at was the virus escaping from a laboratory. We concluded this was extremely unlikely."
Feb 16th 2021
EXTRACT: ".... these men were completely unaware that they had put their lives in the hands of doctors who not only had no intention of healing them but were committed to observing them until the final autopsy – since it was believed that an autopsy alone could scientifically confirm the study’s findings. As one researcher wrote in a 1933 letter to a colleague, “As I see, we have no further interest in these patients until they die.” ...... The unquestionable ethical failure of Tuskegee is one with which we must grapple, and of which we must never lose sight, lest we allow such moral disasters to repeat themselves. "