This month I ran more than 20 metres carrying fresh gelada faeces on a rock (trying to photograph the defecator) and learned to tell females apart by the length of their nipples. It's all in the name of science. I love my job! I am living in a monkey soap opera — gelada baboons quarrel and have sex daily, providing us scientific voyeurs with hours of data-gathering.

All I miss is free time. I'd forgotten how much time is consumed by the process of gathering and digitizing behavioural data. Still, I'm an absolute nerd. I find it exhilarating to see the information increase, and to transcribe gelada vocalizations painstakingly recorded through the hazards of windy weather and tourist encounters. New ideas are already brewing in my mind, new things on which to focus, new questions to ask. (Do rank, spacing and/or hormones affect their contact calling?) My brain works in spite of the oxygen deficit!

Perhaps I am sacrificing some ordinary social skills, though. I am learning to identify some 100 geladas by their unique individual quirks or characteristics. The downside? I seem to be classifying new people as if they were geladas. Just the other day I caught myself comparing one man's straggly whiskers with another's skewed moustache and thinking, 'These males are easy to tell apart!' I foresee problems readjusting to the human soap opera when I leave the field.