Durian Is Not The Only Fruit: On Reciprocity and Hoarding in the Age of the Coronavirus

Durian on tree

Adam Oliver, London School of Economics & Political Science (LSE)


Ever since we descended the trees and became ground apes, in the search for nutrition and to afford protection to the group, humans have acted for mutual benefit. We had to: our very survival depended on it. Our hunter-gatherer ancestors used, and possibly further developed, this tendency to good effect; an individual acting alone may have been able to catch more energy-dense meat than he could have possibly consumed on a ‘lucky’ day, but the unlucky days would have been far greater in number. It made sense for him to share his quarry with those who had none, and for those to whom he offered sustenance to reciprocate when their individual fortunes were reversed.

Reciprocity – returning kindness with kindness, favour with favour, good intentions and actions with good intentions and actions, and their negative counterparts – developed because it benefits the groups to which we belong, and by extension it benefits all of us individually also. As societies progressed, they may have become more atomised, but an implicit recognition that reciprocal motivations had evolved to benefit all of us remained, and was enshrined in the closely related concept of the golden rule – i.e. treat others as you yourself would like to be treated – in all of the world’s major religious and quasi-religious codes. The French anthropologist, Marcel Mauss (1954), in his classic book, The Gift, for instance, noted that the Latin do ut des and the Sanskrit dadami se, dehi me, which can both translate to ‘I give in order that you may give’, are found throughout Western and Eastern religious texts, and statements that emphasise the normative importance of reciprocity are of course common in the Old and New Testaments, the Torah, the Quran and the Analects of Confucius. As noted by the evolutionary biologist Robert Trivers (1971), reciprocity is central to all known cultures.

So why, as witnessed by the widespread panic buying and hoarding behaviours since the outbreak of the coronavirus pandemic, have many people been driven by egoism at a time when the better angels of their nature are most needed?

From his writings of more than forty years ago in his book, Life on Earth, David Attenborough offers a clue, not directly in relation to us, but with respect to our close cousins, the orangutans. In the wild, orangutans are selfish, solitary creatures, and Attenborough wrote that their:

preference may well be connected to their size. Orangs are fruit-eaters, and, being so big, have to find considerable quantities of it every day to sustain themselves. Fruiting trees, however, are uncommon and widely scattered through the forest, at widely varying intervals. Some only bear fruit once every twenty-five years. Others do so almost continuously for about a century but on one branch at a time. Yet others have no regular pattern and are triggered irregularly by a particular change in the weather such as a sudden drop in temperature that precedes a heavy thunderstorm. Even when they do produce fruit, it may only hang on the tree and be edible for a week or so before it becomes over-ripe, falls or is stolen. So the orang have to make long journeys, continually searching, and may well find it more profitable to keep their discoveries to themselves  (Attenborough, 1979/2018, pp.322-323).

In short, since orangutans particularly value the fruit of the durian tree, they face extreme scarcity in their food source, and may have evolved as egoists as a consequence. They perhaps have just enough to survive for themselves; if they shared the little they might find at any particular moment in time they might die. In such extreme circumstances, from a survival perspective, pure selfishness makes sense, and it is not implausible that we too, as a species, are driven towards egoism when similarly required to do so. It makes less sense, however, for people to act egoistically when extreme scarcity is not real, but is merely perceived; acting selfishly when there are sufficient resources for everyone will lead to situations where some have more than they need, while others will experience the scarcity that could otherwise be avoided (the avoidance of which, as noted earlier, is partly why reciprocity evolved as a fundamental motivator of human behaviour to begin with). Unfortunately, the perceived scarcity of food (and toilet rolls, handwash etc.), exacerbated by some sections of the media, has resulted in panic buying and hoarding in many countries during the ongoing coronavirus pandemic, which is starting to cause real and unnecessary hardship for some, including people on whom all of us – including the hoarders – rely [1].

I realise that, in those who choose to read this blog, I am preaching (no pun intended) to the converted, but if we all keep the golden rule – to treat others as you yourself would like to be treated – to the fore of our minds during this crisis and beyond, then the groups – the societies – in which we live will benefit, and, by extension, all of us are more likely to benefit also.

Reciprocity is a fundamental driver of human behaviour that evolved for these very reasons – and can probably be used, by governments, the media and others, to motivate other beneficial practices, such as social distancing and handwashing also. There are, and probably will, be few times in all of our lives when the will to act and behave reciprocally – to look out for our fellow humans in the hope and expectation that they will do likewise – is more important than it is right now.


Adam Oliver is a behavioural economist at the LSE. He is the author of the book: Reciprocity: The Art of Behavioural Public Policy, Cambridge University Press (2019)


Attenborough, D. 1979/2019. Life on Earth. London: William Collins.

Mauss, M. 1954. The Gift: Forms and Functions of Exchange in Archaic Societies. Glencoe, Illinois: The Free Press.

Trivers, R. L. 1971. The Evolution of Reciprocal Altruism. The Quarterly Review of Biology 46: 35-57.

[1] See https://www.bbc.co.uk/news/av/uk-england-york-north-yorkshire-51966337/coronavirus-nurse-s-despair-as-panic-buyers-clear-shelves for a take on the disturbing shortage of food faced by a critical care nurse in England following her 48 hour shift.