Modification of ostrich eggs by carnivores and its bearing on the interpretation of archaeological and paleontological finds

Abstract

This paper presents the results of experiments designed to interpret the significance of scatters of modified ostrich eggshell dating to the Middle Stone Age. The eggshell pieces were recovered from an open-air, archaeological context in the Geelbek Dunes of the Western Cape, South Africa and exhibited conchoidal fractures on their inside surfaces. These finds resemble the openings of ostrich eggshell water flasks described from many southern African sites. The experiments examined the processes necessary to create such openings, focusing on the experimental feeding of ostrich eggs to carnivores at the Tygerberg Zoo near Cape Town, as well as the systematic comparison of data from archaeological, ethnographic and other experimental contexts. The results demonstrate that all of the categories of data overlap significantly. This insight complicates the positive identification of ostrich eggshell water flasks when only fragmentary evidence is preserved. Thus, criteria to differentiate between ostrich eggshell flasks and the case of carnivore feeding are offered.