Another mosquito lies squashed in your hand, surrounded by the blood it just sucked out of your upper arm. You're dripping sweat. For those who have done their share of geological fieldwork in the tropics, it's always wonderful to go there. It's even more wonderful to come back. The climate is exhausting for most of us, transforming hills into mountains when one climbs them on foot, making field days seem endless.
Insects are a major concern.
Not only can they be extremely irritating, they also transmit numerous diseases that will haunt you for years, or even kill you. Malaria is no picnic. Then there are lots of unfamiliar animals and, last but not least, homo sapiens. Dr. Richard Leaky has studied some of the oldest human remains in East Africa, and we'd prefer not to add our much more recent remains to his collection. Humans are much more unpredictable than animals, especially when they are engaged in tribal warfare.