Unfit for Purpose: thesis on human evolution and the modern world gets lost in the weeds

Unfit for Purpose: When Human Evolution Collides with the Modern World

Author: Adam Hart

ISBN-13: 978-1472970992

Publisher: Bloomsbury

Guideline Price: £16.99

Ever get the feeling that, like Brian Wilson, you just weren’t made for these times? Ever get fat, had an allergy, suffered from a food intolerance or chronic asthma? Did you ever get stressed, fall for fake news or develop an unhealthy relationship with drink, drugs or social media? Have you ever wanted to hit someone? Have you ever hit someone?

According to Unfit for Purpose, these are particularly modern discontents, and there is a single explanation underlying all of them. In recent history, author Adam Hart hypothesises, the human environment and human society have changed so rapidly that our physical, intellectual and emotional evolution can’t keep up. Hence its subtitle: When Human Evolution Collides with the Modern World.

In a time of abundant cheap calories, this leads to an obesity pandemic, food intolerances and gastric disorders

For instance, the book suggests, our digestive systems, and in particular our gut bacteria, evolved to process a much simpler, more “natural” diet than most of us now consume. But our genetic heritage, both physical and psychological, predisposes us to shovelling down as much as we can, while we can. In a time of abundant cheap calories, this leads to an obesity pandemic, food intolerances and gastric disorders.

Similarly, although the use of alcohol and drugs has been detected deep into human evolution, recently developed techniques of selective breeding and chemical refinement mean we can now consume much larger quantities in much higher concentrations, fuelling addiction.

Fight-or-flight responses designed to give hunter-gatherers an edge in their hostile environment also kick in whenever we get a big bill or a passive-aggressive email from our boss, leading to unnecessary and harmful levels of stress. Exposure to violent imagery in entertainment and online has, it says here, made us more aggressive and violent. An evolved tendency to tribalism and in-group trust has combined with always-on modern media to spread dubious content, turbo-charging a fake news environment.

Lost in the weeds

These arguments are, to various degrees, intuitively appealing. It’s clear that we are all, on a basic biological level, still apes, but also that we have long since outgrown our primordial savannahs, having devised calculus and reality shows and ice-cream, and looked at the stars.

There is also a great deal of scientific evidence to support the thesis that we are running ahead of our own genetic heritage, and Hart, a doctor of entomology, BBC documentary presenter and professor of science communication at the University of Gloucestershire, is careful to lay it out in detail.

Yet there is also a great deal of evidence against each of Prof Hart’s propositions, and – as a good scientist – he carefully lays this out too. All too often, striking assertions, backed up by impressive studies, fade away into counter-claims and caveats, leaving the reader unsure what point, if any, has been successfully made. One of the reasons why humanity evolved to walk on two feet was so it could see over tall vegetation, yet this book spends a lot of time lost in the weeds.

For example, a section on coeliac disease, which begins by linking a startling spike in the condition among Swedish infants to a temporary increase in gluten in early diet, goes on to acknowledge – as in many other cases that this book examines – that many other factors, both associative and causal, could also have been at work.

A discussion of the possible long-term health benefits of "natural" vaginal birth, as opposed to C-sections, founders in a welter of counter-studies and complications

“With every step forward in our understanding we seem to take another step back and it is instructional that such a prevalent disease, which appears on the face of it to be rather simple, can be so complex,” he concedes.

Similarly, a discussion of the possible long-term health benefits of “natural” vaginal birth, as opposed to C-sections, which are thought to deny newborns the benefit of a “bacterial baptism” as they pass through the birth canal, starts with bold figures, but then founders in a welter of counter-studies and complications.

“The problem is that there are a wealth of confounding factors that are horribly interrelated and also contribute to bacterial differences and to subsequent health including antibiotic administration, labour onset, maternal weight. maternal diet and, as we shall see shorty, breastfeeding.”

Thoughtful appraisal

Although sometimes jocular in tone, the book is a thoughtful and honest appraisal of a serious thesis, which takes painstaking care to avoid those trite anecdotal conclusions that Prof Hart dismisses as “Just So” stories. He is aiming to tell us nothing less than the truth, but if he hopes for the grand sweep of books such as Juval Harari’s Sapiens or Jared Diamond’s Guns, Germs and Steel, he loses his way in the minutiae of individual genes, conflicting studies and the Latin names of intestinal bacteria.

Sometimes, too, the basic meaning is hard to follow. For instance, Hart discusses what he initially posits as modern humanity’s increased tendency to violence and aggression. (Caveat: “It is possible to find equally confident assertions that we are more violent than we were in the past, that we are less violent, that violent crime is increasing, decreasing, or staying the same, or that homicide rates have gone up or down.”) He cites studies that “show that if someone is being insulted, then the mere sight of a gun can cause the insulted person to lose self-control and retaliate aggressively”.

What is this supposed to mean? That people are more likely to get thick when the person who is harassing or bullying them is pointing a firearm? If so, there are a lot of people from, say, Northern Ireland over the age of, say, 35, who could tell him different.

These days any popular book that sets out a problem is also obliged to suggest a solution, however hopeful and vague

If the professor is right, and we are indeed the victims of genetic determinism, one would assume that there isn’t much we can do about it in the immediate here and now. These days, however, any popular book that sets out a problem is also obliged to suggest a solution, however hopeful and vague. Thus, Hart concludes, “It sounds cheesy and trite, but evolutionary insights suggest we need to work on ways to bring people together. Maybe John Lennon was on to something.”

The reference is presumably to the song Imagination. But Lennon’s Everybody’s Got Something to Hide Except Me and My Monkey would also work.