The coronavirus outbreak has shocked and surprised the world, but for many disease ecologists, Covid-19 may be just the beginning of many more mass pandemics. There is now growing evidence that we humans could be to blame for the crisis. This week on Down to Earth, we look at the potential link between the destruction of our ecosystems and the rise in animal-borne diseases, but also at how nature could be one of our greatest allies in the fight against Covid-19.