Our evolutionary heritage, extending from the deep roots of our phylogenetic history to more recent genetic changes, for example in response to agriculture, provides the fundamental basis for our ability to deal with whatever complications the world throws at us. The anthropogenic nature of much of the modern world means that we are often throwing complications at ourselves and, as we have seen, our evolutionary heritage is not always able to cope. In fact in many cases our heritage is working against us, leaving us vulnerable to all manner of problems in the world we have created. These problems, ranging from our diet to addictions and from violence to fake news can be explained in part by the mismatch that has developed between the modern world and the environment in which we evolved.
Of course, we are far more than simply the product of our genes and it is the interplay between our genetic ‘nature’ and the ‘nurture’ of the environment, as well as our unparalleled ability to learn and adapt mentally, that defines us and allows us to function. The current human population is a testament to the fact that despite being ‘unfit for purpose’ in so many ways, we nonetheless manage to do more than just scrape by. Our ability to shape and construct our own environment makes us the greatest of all of nature’s engineers but, unlike the nutrient cycling achieved by termites in their impressive mounds or the European beaver’s creation of biodiverse flooded forests, our environmental engineering mostly suits just one species: us.
One could argue that the greatest example of our ‘unfitness’ in the modern world is that the evolution of a brain large and complex enough for abstract thought and social cooperation, coupled with our unusually dextrous hands, have provided the ideal tools to engineer our own destruction. The past 75 years, just three generations from an evolutionary perspective, have seen the rise of cheap air travel, widespread car ownership, ‘consumerism’, the internet, real-time globalisation and a tripling of the human population. We are degrading our own habitat, changing the climate and generally dirtying our own nest, and the solutions are not going to come from some miraculous set of mutations and evolutionary changes. Even if it were possible to evolve our way out of the environmental mess we are rapidly making, and let’s be honest, it isn’t possible, we simply don’t have the time. If we are to avoid an environmental disaster of our own making then we going to have to use the most powerful and important evolutionary legacy of all, and the reason we are in this mess in the first place: our brain. The problem is that when it comes to planning for the future, evolution has a lined up a couple of other serious mismatches that we are going to have to negotiate.
Natural selection: selfish and immediate
We are in the unique position of knowing that we are heading for existential trouble, knowing why and being able to do something about it. No animal has ever before had this luxury. Dinosaurs roaming the Earth at the end of the Cretaceous didn’t look up to see an asteroid approaching and decide to make a plan. I undertake research on a fenced wildlife reserve in South Africa. The antelope grazing there on the rich grassland don’t have the wherewithal to plan and enact a regime of rotational burning to keep the grass capable of sustaining them into the future. Without management these animals would eventually eat all the grass and, being unable to move on to pastures new, would starve. This has actually happened on a number of reserves that fail to manage habitat and stocking densities correctly, and it is a good analogy for what the future on Earth might be for us. Unlike wildlife, humans can make plans and we can manage resources if we choose to. At this moment, which many are suggesting is a crucial one in terms of our long-term survival, making a plan and managing our resources are precisely the things we need to do. This will require us to think beyond our own limited self-interests and plan far into the future, two characteristics that evolution has tended to work against.
Natural selection and evolution are all about the ‘here and now’ and the immediate future. What behaviour will gain you a mate? How can you avoid being eaten? What maximises offspring production? Evolution is not striving towards a grand plan, some relentless quest towards the perfect future solution. The idea of evolution working in some goal-directed way is called teleology and teleological thinking is very easy to slip into if you’re not careful. Giraffes don’t have long necks because they ‘want’ to reach leaves high in the canopy. Rather, giraffes evolved long necks because across generations individuals at the longer end of the spectrum of neck length, which had some heritable component, were more successful than those with shorter necks. At some point the costs of extreme height and a long neck (the ever more robust mechanical support required and the high blood pressure necessary to supply the brain) exceeded the benefit these traits provided and put the brakes on the evolution of neck length. At no point during the process were giraffes, or evolution, planning for the benefits of future generations.
While we rightfully pride ourselves on our intellectual abilities, our brain is simply another adaptation that enables us to leave more offspring. This inevitably tends to make the brain a tool for the here and now. We are very good at attending to those issues which are immediate, like all animals, because it is the ‘present’ that brings challenges that we have to overcome. That is not to say we cannot make plans for the future; clearly we can and do. But it does suggest that intellectually we might have a different relationship with the abstract future than we do with the concrete present. Other animals can also make plans for the future; squirrels bury nuts for themselves for winter, while some birds store seeds in holes in tree trunks that they will find (using their remarkable spatial memory) and eat later. What we don’t see in nature though are squirrels or birds intentionally storing food for future generations. Of course, buried nuts that are forgotten may germinate and produce trees that could feed future generations but a lucky accident is hardly future planning. Nut-burying behaviour and the cognitive structures required to find them again have been selected because of advantages accruing to the individual doing the burying in the short-term future. The very real present is always more important than the abstract future, and it seems more than reasonable to suggest that thought processes that can get an individual out of trouble right now, and that originate from neurological arrangements with a genetic basis, will flourish. We will return to the issue of our relationship with ‘future us’ shortly, but for now we also need to consider our relationship with everyone else, because as we will see, this has an interesting part to play in considering how we think about the future.
Self-interest is hard to ignore
Given that selection acts on individuals, we should have a strong tendency to value ourselves above others. Certainly self-interest is the rule in most of nature, and we successfully make sense of the evolution of much of animal behaviour by viewing it through the lens of ‘selfishness’ and individual benefit. Of course, there are plenty of humans who seem to act selflessly, who give their lives for others, who devote their time to helping others, who give away their fortunes and so on. Equally, there are also plenty of people who aren’t violent (Chapter 7), don’t get addicted to substances (Chapter 8), can function entirely healthily on social media (Chapter 6) and have a wonderful gut flora (Chapter 4). The key word here, as indeed has been the case throughout this book, is tendency; the question we are really asking is, do we have a tendency to value our own interests over those of others? If we accept that some of our thinking processes are the hard-wired consequence of evolution with the chance of being further honed by experience and learning, and that selection acts predominantly on individuals, then thought processes that tend to support self-interest seem more than likely. But as we developed into a more social species, and the benefits of being social began to emerge, then selection would also seem likely to favour intellectual processes and outlooks that were more favourable towards our social group (very often our kin). It is this balance between ‘self’ and ‘group’, or ‘others’, that is crucial.
Even in groups we often think of as being solely about ‘group interest’ we can still see the signature of self-interest. Honeybees are often portrayed as the ultimate in harmonious group living. The colony is headed by a single queen who lays all the eggs. She is the ‘breeder’, the ‘reproductive’, and the female workers that emerge from these eggs are sterile (non-reproductive). The workers toil ceaselessly to grow the colony until at some point it is large enough to produce a swarm. A large group of workers (about a third of the total number usually) departs with the old queen while a new queen is reared inside. It is the colony itself that is reproducing (we start with one colony and a swarm leaves us with two) and it is the colony that must get large enough to be able to produce a swarm. The queen–worker division of labour, with queens laying eggs and workers doing all the other work, is efficient and effective but it implies that workers can only benefit from what is called ‘indirect fitness’, by helping to rear a sister queen who will head a new colony of their nieces. But the reality is that worker bees, and indeed the workers in many ant, social bee and social wasp colonies, are not in fact completely sterile and can gain some ‘direct fitness’ by having offspring. They can lay unfertilised eggs, which through a process of sex determination called haplodiploidy will hatch into males. If the queen has mated more than twice then the relatedness within the colony drops to a point where the workers value other worker-laid sons (their nephews) less than their own sons and less than their brothers (the queen’s sons). In this case, even though any given worker wants to lay eggs, the worker collective will seek to destroy eggs laid by their sister workers. This so-called worker policing can be highly costly, wasting resources and time, but self-interest can nonetheless allow for worker egg-laying to persist. That such self-interest is evident, even in much more group-oriented species than we will ever be, shows what a very important role it has.
There’s room for hope
Given the importance of self-interest and cooperation in our everyday lives, the intellectual interest that we clearly have in our own behaviour and the links to wider issues such as morality, it is no surprise that psychologists have done their best to answer the question ‘are we selfish?’ The overall conclusion is put rather nicely by Emily Pronin and colleagues in a 2008 paper that we will return to shortly and that is largely concerned with investigating how we think about ‘future us’. They put it like this: we have a ‘tendency to make decisions that neglect others relative to the self’.1 A guarded, carefully worded if damning statement. However, recent work suggests we could be less instinctively selfish than we might think.
In a paper entitled ‘Spontaneous giving and calculated greed’ published in Nature in 2012, Joshua Greene and colleagues set up an experiment whereby they could investigate the effect of ‘thinking’ on our behaviour.2 The idea underpinning the research is that we might act more selfishly, displaying what they term ‘rational self-interest’, when we get a chance to think about our actions, and less selfishly if we act under a time restraint such that we can’t think too much about what we are doing. On the other hand, as they put it, perhaps we are simply ‘predisposed towards selfishness, behaving cooperatively only through active self-control’. In other words, some time to think might instead make us better people, less inclined towards self-interest. Their experiment allowed them to distinguish between these two outcomes and to determine the contribution made by intuition and reflection on our selfish/selfless behaviour.
The experimental set-up was very similar to the investor-trustee game we met in Chapter 9 when we considered the role of oxytocin in developing trust. Participants were assigned roles, given money to invest and once again the experimenters multiplied the payment (this time doubling rather than tripling the amount invested) before dividing up the spoils depending on decisions made by the trustees. The interesting variation added by Greene and colleagues was to introduce the element of time; in some of the games the participants had to make their decisions rapidly (within 10 seconds), but in others they were forced to take time to reflect on their decision. Rapidly made decisions are more likely to be the product of ‘intuition’, evolved heuristics that help us in the here and now, whereas decisions that come from reflection are likely influenced by higher-level intellectual processing. The results across all the experiments showed that when participants were forced to make a decision rapidly they were more cooperative than when they were forced to reflect on their actions. The overall conclusion was that cooperation is intuitive. They suggest that this is because of ‘cooperative heuristics’, simple cognitive rules of thumb, which kick in when we need to make rapid decisions. Overall, cooperation is typically advantageous and so such a rule of thumb mostly works out for us. Reflection, the time to think about a decision, on the other hand tends to lead us away from cooperation to act more selfishly.
The ‘social heuristic hypothesis’ provides a way to interpret these findings by using, as we would now expect, a combination of nature, nurture and learning. The hypothesis suggests that individuals who regularly experience cooperation, and who regularly benefit from it, will tend to develop more cooperative heuristics that kick in as the default response in social situations. If you have intuitively acted cooperatively in the past, and those actions have benefited you, then the heuristic is reinforced. Alternatively, those who have been rewarded for selfish behaviour will tend to develop uncooperative heuristics. There is variation across the population for this intuitive side of our behaviour (some people are more selfish than others), but the social heuristic hypothesis predicts that deliberation will tend to favour self-interested behaviour in everyone.
Greene and colleagues found very clear evidence that our intuitive ‘default’ mode is selflessness, and their work has become highly influential. However, while some studies have confirmed their original findings, others have found the complete opposite, with reflection leading instead to more cooperation.3 To try to make sense of the developing confusion an analysis of 21 separate studies replicating the original work was published in 2017.4 This analysis showed ‘essentially no difference in contributions between the time-pressure [intuitive] and forced-delay [reflection] conditions’. Their conclusion was that the original finding was the product of biases arising from excluding people who didn’t meet the time constraint. For now, the jury is well and truly out on whether we are less self-interested when we make rapid decisions. What is interesting though is that, regardless of the validity of the social heuristic hypothesis, studies find a mix of self-interested and selfless behaviours. While we can argue about the balance between intuition and reflection, and the contributions of innate hardwiring, learning and experience, the fact remains that a tendency towards self-interest is an important component of our evolved behavioural repertoire. We need to remember that tendency as we consider the future.
The very real problem of the very abstract ‘future us’
When we consider the future, and more specifically ‘our’ future, we tend not to think of ‘future us’ as being the same person as ‘present us’. We tend to view the hypothetical future version of ourselves as someone else, which means that we also tend to view the future as though it is happening to someone else. This overlap between what psychologists call temporal distancing (the difference between now and times in the past or future) and social distancing (the social distance between you and other people) is hugely relevant when it comes to thinking about how we might plan for the future. The sort of planning we need to do requires us to take decisions not just for future versions of ourselves but for future versions of everyone else, and indeed for future versions of people not yet in existence and their future offspring. That is an awful lot of temporal and social distance.
An interesting but not especially satisfying piece of evidence that we view our future-selves as different people comes literally from observations of how we view our future-self. When picturing future events, we tend to see our future-self from the perspective of an external observer, while we perceive our present-self first hand and experientially, from within. A much more satisfying and solid evidence base though comes from a series of experiments that were specifically designed to investigate this shift in perspective when it comes to the future.
One experiment involved a disgusting drink. Participants, in this case students, were asked to make either real or hypothetical decisions about how much of the disgusting drink should be drunk by themselves or another participant, either in the present or in the future. The set-up was that the drink was to be consumed as part of a fictitious scientific experiment about mood and perception. You cannot experience your present self (or your ‘on-going self’ as the experimenters term it) hypothetically and so the tendency is for the on-going self to focus attention on immediate subjective experiences. The prediction was therefore that participants making real decisions would choose to allocate more disgusting drink for their future-selves and for other people’s future-selves than to themselves in the present. To add some real-world jeopardy to the future-based decisions, the students were told that they would have to drink the future disgusting drink (water, ketchup and soy sauce) early in the next semester and that they would lose academic credit if they didn’t. Participants making hypothetical decisions were told to imagine themselves allocating the disgusting drink to the various different parties, including themselves. Sadly for the casual observer, in neither the real nor the hypothetical case, and neither in the present nor the future, did anyone actually end up drinking the disgusting drink.
In the hypothetical condition there were no differences between the amount of disgusting drink allocated to present and future selves or to other people. It seems that when it comes to hypothetical situations, we don’t really distinguish. When it came to making what the participants thought was a real decision, however, the experimenters found a very big difference. In that case, the amount allocated by participants for themselves to drink right now was less than half that allocated to their future-self. The amount participants allocated to other people right now was, interestingly, identical to the amount they allocated to their future-self. In other words, when making decisions we tend to treat ‘self’ far better than ‘others’ but we don’t carry this preferential treatment forward into the future. The disgusting drink experiment shows us that our priorities are firmly fixed in the order self first, then future-self and everybody else (regardless of when they exist).
Another experiment confirms this present–future bias. Again the experiment used students, this time asking them to volunteer time for a hypothetical peer-mentoring and tutoring programme initiated by a researcher posing as a fellow student. The experiment took place during the run-up to stressful and important mid-term examinations. Participants were divided into four groups:
1. self-present (‘how much time would you give up this week?’);
2. self-future simple (‘how much time would you give up during the next midterm period?’);
3. other (‘how much time do you think other students could spare?’); and
4. self-future/same feelings (‘how much time would you give up during the next midterm period given that then you will be feeling exactly as stressed and anxious as you are right now?’).
The last group, self-future/same feelings were additionally told to remember that they would have about the same amount of work that they do right now, that they would still have the same concerns about their work–life balance and that they were going to be the same person that they are right now. The findings were very clear. Fewer minutes were volunteered for self-present (27 minutes) than for self-future simple (85 minutes) and for other people (a whacking 120 minutes). Once again the results show that we prioritise ourselves over all other people, including future versions of ourselves. What is really interesting is what happened when the experimenter took pains to outline to participants what ‘future them’ might be like. When participants were told that future-them was basically just present-them, they began to treat future-them much more like present-them, offering far fewer minutes (46 minutes).1 The lesson here is that if we are reminded that we are going to be the same people in the future, with the same experiences, anxieties and fears, then we start to treat future us rather better. What we don’t do is treat other people any better, now or in the future.
Other experiments, looking for example at receiving junk email on behalf of someone raising money for charity or examining the amount of prize money we take now or in the future, confirm the same basic findings. We discount future versions of ourselves and we prioritise ‘present-self’ over anybody else. As disappointing as this tendency might be, it cannot really come as any surprise. Just as in other animals, cognitive structures in our brains have evolved to allow us to function as here-and-now creatures that ultimately value self-preservation.
Of all our evolved tendencies, it is perhaps our attitude towards the future that might prove to be greatest mismatch in terms of impact. It is also the mismatch that might be the easiest to overcome. What the mentoring experiment shows us is that when we can engage our brain and think about the future, when we are given a chance to imagine future-us as a person identical in subjective experience to present-us, we start to treat future-us a little better. Whether that opportunity to think makes us less selfish towards other people (both now and in the future) is open to debate, but as we’ve seen, some experiments do suggest that this might be the case. There might just be some hope for us after all.
Saving ourselves
We make hundreds of decisions every day that have an impact on us and others, and on future versions of everyone. We have seen in previous chapters that taking an evolutionary approach towards understanding the mismatches that underlie some of our modern-world problems can give us insight into how we deal with problems like obesity or addiction. The big difference between the issues covered in earlier chapters and the ones we are considering now is that evolved tendencies to lead humans towards conditions like obesity or addiction can cause major societal problems, but they are not existentially threatening for humans overall. They harm many of us and they kill some of us but they don’t affect us all. That is not necessarily the case with the selfish, future-discounting behaviours that we see currently degrading the planet. So, can considering our evolved tendencies in the way we think about other people and the future give us insights into how we might tackle the biggest problems that we face? I think it could.
At the moment, much of the environmental rhetoric is focused around blame, and much of that blame is levelled at countries with rapidly developing economies underpinned by models of power generation and the types of industries that tend to pollute (China, for example). That, of course, was the same in developed countries like the UK and USA not that long ago. It is nearly always politically expedient to blame others (remember social identity theory from Chapter 9?) but this just reinforces the idea of ‘them and us’. It is a toxic approach that plays to our basic individual and group-level selfishness. We need to understand that globalisation is not just a way to get cheap plastic shoes from Indonesia; with the right mind-set, it is a perfect opportunity to overcome our individualistic and ‘tribal’ tendencies. As tentative and guarded a conclusion as it might be, we have seen that the more we see other people as part of our group, as ‘us’, the better we might treat them. 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.
Then, of course, there is the fact that we tend to see future outcomes for future-us as being events that happen to someone else. This is a fundamental problem if our goal is to change behaviour today for the benefit of future generations. It is a problem that is made far worse by the fact that, like the disgusting drink in the future-self experiment, the medicine is going to be hard to swallow: we must consume less; we must pollute less; we must change our diets; we have to fly less, drive less and so on. Future us will have a lifestyle that is rather different, and less appealing, than present us. Perhaps to make us drink the medicine we need to play to our evolved foibles? A sensible first step would certainly be reinforcing, regularly and forcefully, the point that ‘future us’ is still ‘us’. Future us will have the same outlook, feelings, hopes and fears as we do right now. Maybe the time has come to accept our limitations and play to our weaknesses? If so, then a better understanding of our evolutionary heritage might just give us some of the insights we need to save ourselves from the most important mismatch of all, and ensure that future generations can thrive on Earth.