Unfit for purpose
The author is a biologist and broadcaster. The premise is that over the long period of time through evolution, humans adapt in certain way because that way yields the best possible chance to pass on gene from one generation to the next. Essentially, humans were fit for purpose (in hunter gatherer style) in environment more than twelve thousands years ago (i.e. when agriculture started spreading). However, changes brought about by social organisation, technology, and information since then are swift (in evolutionary terms). Far swifter than humans can adapt leading to mismatches between humans and modern urban environment in which we all live.
Given the material explored in the book e.g. sex, obesity, gluten intolerance, fake news etc. it could have been more humorous, it would have been a lot easier to read. The book took novel angles to analyse interesting premise nevertheless. The focus was on debunking simple evolutionary explanations rather than establishing ones. It was a little short on how to improve the current situations. In any case, it’s unrealistic to expect the author to offer valid quick fix to all long standing problems.
The book is concerned with the aspects of the human animal that have evolved for a world in which we no longer live, or those aspects that were rather useful in our evolutionary past but are coming back to bite us now that we have altered our environment.
Obesity epidemic
Before agriculture when our ancestors lived as hunter-gatherers, the hunting would not always have been good. Animals can be remarkably hard to find and kill, while plant bonanzas are highly seasonal. Full bellies might be easy to imagine but hard times and hunger would never have been far away. Homo sapiens being highly adept at laying down fat stores in times of abundance to survive the leaner times ahead. We now live in times of absolute feast but are physiologically ever-prepared for a future famine that will almost certainly never come, but just in case it does, our bodies lay down fat and so we balloon.
Counter argument
Famines, the primary selection factor in driving the evolution of putative thrifty genes, do not happen very often, do not have a large effect when they do and the individuals killed by famine in a population are not those that are consistent with the hypothesis.
The alternative explanation, the drifty gene hypothesis, asserts that a lack of predation caused our upper weight limit to ‘drift’ upwards, unconstrained by strong selection pressures.
Overall, the simple idea that we are fat because we are storing up for a forthcoming famine, as seductive as it undoubtedly is, doesn’t currently stand up to full scrutiny across all populations.
Hygiene hypothesis and allergy by Strachan '89
It was proposed that modern environment was too clean for children. They were not exposed to enough immunological challenges so their immune system would not properly develop leading to all kind of allergies - heightened immune responses to non-harmful stimuli.
According to major review in 2012, the idea that poor hygiene in itself would be protective [in other words, that a dirty house protects your children from allergies] is now generally refuted, although it is still discussed in the popular media.
Stress
A squirt of adrenaline and some raised blood pressure and heart rate is ideal if you lose your footing while out collecting berries or during the final stages of a hunt (these are after all potentially existential crises), but is clearly overkill in response to a ‘difficult’ email from your boss. Despite that, our basic biological set-up is largely unable to tell the difference.
What to do
Stroking cats can reduce heart rate and blood pressure in humans. Indeed, ‘socially grooming’ your cat has been shown to reduce the chance of stroke, a major killer related in many cases directly to high blood pressure, by up to a third.
Think about drug and cost saving, instead of prescribing blood pressure lowering drugs which collectively cost a fortune, we could prescribe “getting a cat”.
Social grooming
It is all about connecting with individuals in ways that develop and nurture alliances and coalitions, cementing and securing relationships and friendships that provide benefits to those involved in the grooming relationships. Its function is not in removing parasites or improving fur condition (which may have been the initial selective advantage in its evolution) but in establishing, developing and reinforcing social networks and relationships.
When monkeys are picking at each other, unmatting fur and eating ticks, what they are really doing is making friends. Through the act of grooming, primate groups can become more stable, which could bring benefits to individual members through strength of numbers and competitive advantage. It is better for the individual to be in a better group, and a better group is one that has strong and stable relationships between group members
Social benefits of gossiping
Gossiping has the twin benefits of reducing stress and bringing people together, acting to bond individuals in just the same way that more obvious physical grooming can achieve.
Addiction
Ultimately the mechanisms involved in drug taking are biochemical, with substances acting at a molecular level in our brains, but for the user the effect is ‘felt’ at an emotional and physical level. Taking drugs stimulates us to feel, often in a highly magnified way, the euphoria and excitation that we have evolved to feel in response to stimuli that were vital for our survival.
Interesting take on ‘war’ on drugs
In 2009 Nutt published an editorial in the Journal of Psychopharmacology entitled, ‘Equasy – An overlooked addiction with implications for the current debate on drug harms’. Nutt outlines the considerable risks and harms associated with horse riding and concludes that there is a ‘serious adverse event’ every 350 exposures. The harm caused by horse riding can include serious paralysis and even death (10 people per year). Ecstasy on the other hand has one adverse event every 10,000 exposures. Using the scale used in the 2007 paper, Nutt concludes that horse riding is far more harmful than ecstasy and yet society feels no need to control this activity. He proposed that we take a mature and rational approach to the actual risk of harm from drugs rather than the perceived risk of harm, the portrayal of which may be politically motivated (the ‘war’ on drugs being a vote winner on many levels) and exaggerated by the media.
Fake news
As a social species we have evolved to trust and most of us tend towards being trusting unless evidence suggests otherwise. We have neural mechanisms that even before we can talk allow us to interpret the ‘truthfulness’ of those around us. Innate neural mechanics, gradually honed through experience, lead us towards believing those who present information confidently. Halo effects, perhaps based on deep-rooted selective advantages linked to mate choice, cause us to be dazzled by certain individuals and corporations.
Cult
By belonging to that group, and identifying as part of it, you become part of the ‘in-group’ and are likely to display in-group biases. These biases mean that you will give preferential treatment to others in your group while also potentially biasing against ‘out-groups. Important aspect of social identity theory is that members of the in-group will seek out negative aspects of the out-group and in so doing bolster the in-group’s self-esteem.