ABSTRACT
N ovember 27, 1966. For one of the authors (Mark Schaller) that was abad day. It was his fourth birthday and his parents threw him a party,with balloons and ice cream and birthday party games. This wasn’t easy because the family was living on the Serengeti plains of Tanzania, where neither balloons nor ice cream (nor very many other young children for that matter) were readily available. Despite his parents’ intrepid efforts, the day was a disaster. Mark’s balloon popped. He dropped his ice cream into the dirt. He cried and cried and cried.
