How do we survive crises – then and now?

How do we survive when the world strikes again? How do we cope when crisis hit? An extreme external incident where the food supply fails and resources dwindle. Should we store food, leave our homes or seek help from the neighbours? Such decisions – and their results – are often referred to by researchers as 'resilience'.

Resilience, often touted as the solution to many crises faced by societies at different times and places, is often expressed in very abstract terms, or as a seemingly stable characteristic of certain individuals, groups, or larger social systems that enables them to endure external crises. However, resilience is best understood as the sum of numerous individual decisions and strategies. It is neither inherent nor immutable, and there is no universal strategy that reliably works across all types of crises.

In a new study published in Science Advances, archaeologists from Aarhus University and the University of Colorado used computer simulations to measure the effectiveness and costs associated with four most common resilience strategies used by people in the past and which are also used by many people around the world today: investment in infrastructure, exchange, mobility, and economic adjustment.

Mobility, investment in infrastructure and strong social ties protect against crises
"We noticed early in our study that economic adjustment performed significantly worse than other strategies across a wide range of crisis conditions. In short, if a crisis hits, it will not be enough to work harder to obtain the necessary resources if there are not enough resources available in the first place", says lead author Colin Wren.

Mobility – moving to a safer area – proved to be a solid strategy with moderate costs but only works if there are better places to go. Exchange, where resources are shared through social networks, works as a mix of mobility and investment. Economic adjustment – tweaking one's behaviour to respond to a crisis – in contrast, proved to be the least effective strategy.

Future Crisis Management 
The conclusions of the study are supported by ethnographic and archaeological analyses, which show that different groups of people engaged in all the resilience strategies studied, resulting in different outcomes.

"What this study also shows is that we can and should look into the past to better understand what resilience strategies worked for our ancestors, so that we can choose the best ones for the kind of crisis we expect to see more of in the future", says Iza Romanowska, one of the study's authors. She does add a caveat though:

"Our results are thought-provoking, even though they come from a fairly simplistic computer simulation and therefore probably can't be applied directly to today's world in a one-to-one way.”