If aliens were to examine a human, they would think we were just slavish organisms designed to feed microbes and carry them around. Our bodies contain ten times more bacteria than cells , and there are an estimated 3.

South Africa is experiencing its severest drought in more than a century. Savannahs – grasslands scattered with trees and scrubs, which cover about half of Africa – are some of the most productive environments of the continent, supporting livestock and rural livelihoods.

About 75% of the new diseases that have affected humans over the past 10 years have developed from animals or products of animal origin.