How rhesus macaques thrived after Hurricane Maria

Who do you take lessons from if you want to learn about survival? Who will you choose as your role models?

As unlikely as it might seem, you could do worse than taking a leaf from the book of our closest primate ancestor, the monkey. That is a lesson drawn from an account published in Scientific American magazine on the 8^th of April 2021.

Lessons from Cayo Santiago

Cayo Santiago is a tiny island off the coast of Puerto Rico and home to some 1,500 rhesus macaques – these colonies of primates have long been the subject of several academic studies.

In September 2017, the whole of Puerto Rico and its islands were hit by Hurricane Maria – it took the lives of around 3,000 people and, of course, plunged the area into survival mode for months on end.

But the island of Cayo Santiago and its troupe of monkeys turned into a microcosm of community resilience while all around it was in tatters. The hurricane destroyed around 60% of the island’s vegetation, for instance, yet nearly all its monkeys survived.

Creating a new social order

The miracle of Cayo Santiago lies in the way its primate inhabitants not only adapted but developed a whole new social order in the face of the devastation, food shortages, and lack of essential shaded areas, that was all around them. Would there be a fight to the death in the competition for scarce resources or would some new sense of community, collaboration, and strengthened bonds emerge?

Against many odds, the latter qualities triumphed.

The monkeys reacted to the radically changed, much harsher, environment by changing their whole social order. From existing social networks, for example, broader and more tolerant connections were formed. Indeed, one of the co-authors of the Scientific American report describes the process as a wholescale shift in the levels of connectedness between individuals and groups of monkeys.

How society might reorganise itself in the face of existential threat

The scientists leading the study of the social behaviour and adaptation of the monkeys on Cayo Santiago believe they may have found clues to the ways in which social organisations adapt and effectively re-wire themselves in the face of serious threats.

What lessons might there be in here for human behaviour under such dire circumstances? The subjects of this study were monkeys, after all, and human beings are just one of the 190 to 448 species of primate.

One of the most encouraging lessons from this study of primates, perhaps, is the suggestion that an external threat – in the shape of a severe natural disaster or example of extreme weather – can actually make an existing society stronger and does not lead to the inevitable wiping out of that community. Instead, the social order adapts, reorganises and re-wires itself, to create a new, more relevant, social order.

Scientists studying the monkeys on Cayo Santiago expected the external threat to force individuals to look inward, clinging more and more to each other, in established social relationships. Instead, there seems to have developed a more tolerant, less aggressive pattern of behaviour towards all members of the troupe and not just existing bonds.

There may be helpful lessons in all of this when we consider possible scenarios in the human context and for social organisation following any disaster or emergency.