During the Covid-19 pandemic, decision-makers around the world have grappled with the question of whether to reopen counties and cities all at the same time or allow less affected places to reopen first. Our research suggests that with sufficient testing and co-ordination, reopening schools and businesses in areas of Ontario without active outbreaks can be as effective as a lengthy provincewide lockdown in minimising total infections while also reducing closures.
It may surprise many readers that we came at this project from the study of climate change negotiations and underwater giant kelp forests.
Famously, lush kelp stands can be rapidly grazed down into rocky barrens by sea urchins – animals little more than spine-covered balls with a mouth. Yet we found that collective urchin behaviour is all-important: sometimes urchins stay close to their shelters and maintain only…