Twenty-five years ago, when I was a young anthropologist working in northern Siberia, the Indigenous hunters, fishers and trappers I lived with would often stop and solemnly offer something to the tundra. It was usually small, such as coins, buttons or unlit matches. But it was considered essential. Before departing on a hunting or fishing trip, I’d be asked if I had some change in my outer coat. If I didn’t, someone would get me some so it was handy. We left other gifts, too, such as fat from wild reindeer to be fed to the fire.