An often overlooked resource: Ostrich (Struthio spp.) eggshell in the archaeological record

Abstract

Ostrich (Struthio spp.) eggshells are present in archaeological assemblages in many regions of Africa and Asia. However, and unlike other artifacts and ecofacts, there are no standardized guidelines for observing and recording non-ornamental ostrich eggshell. Here, we review prior research that focuses on facets of the taphonomic history of ostrich eggshell assemblages, and we document results from our actualistic studies of the changes in color that occur when ostrich eggshells are heated. We further propose some guidelines for recording ostrich eggshell in archaeological contexts, which include burning categories and quantification methods. These guidelines are intended to facilitate the development of large, comparative, and standardized ostrich eggshell data sets that will contribute to our understanding of site taphonomy and past human behavior.

Raman Spectroscopy Detects Amorphous Carbon in an Enigmatic Egg From the Upper Cretaceous Wido Volcanics of South Korea

“…The thermally matured organic matter (i.e., blackened amorphous carbon) would be, at least partially, responsible for usual dark-color of Korean fossil eggshells (e.g., Janssen et al, 2011;Collins and Steele, 2017) along with blackening chamosite, a mineral that is widespread in Korean Cretaceous vertebrate bones and invertebrate shells (Kim et al, 2018; Supplementary Figure S4). In fact, palynomorphs from the Cretaceous deposits in Korea are heavily altered by igneous activities as well (Choi, 1985(Choi, , 1989Yi et al, 1998Yi et al, , 2004, supporting that thermal maturation of the carbonaceous material was a universal phenomenon for Cretaceous fossils in the Korean Peninsula.…”

Diachronic Change in the Utilization of Ostrich Eggshell at the Late Paleolithic Shizitan Site, North China

“…Color is observed by naked eye and indicated using general terminology. Based on previous studies of OES heat treatment and post-depositional changes cited below, we infer that color changes were brought about primarily by heat treatment, likely due to exposure to open fire, which is also supported by observations of surface changes such as crackling, but this must be tested and experimented further across all OES data sets as the particular processes by which some color changes occur still remain unknown, such as for the black color found at Shizitan (Collins and Steele, 2017). For Shizitan, a series of…”

“…However, the particular process by which they can become this color remains unknown despite actualistic studies. For example, Collins and Steele (2017) note that no experimental studies of heating using ovens or kilns has been able to reproduce black OES but suggest that oxygen availability and the introduction of organics need to be considered.…”

“…Research over the past decade on OES ornaments has focused on three sites because they have undergone controlled excavations, namely, Shizitan (Song et al, 2011;Song and Shi, 2013a;Song and Shi, 2013b), Shuidonggou (Wang et al, 2009;Wang, 2010;Wang et al, 2011;Wei et al, 2017), and Yujiagou (Nihewan Basin) (Wang et al, 2020). This work has included studies on the origins of OES products, manufacturing techniques and sequences (Song and Shi, 2013a;Song and Shi, 2013b), and related experimental archaeology (Wei et al, 2017;Wei and Gao, 2020) and follows upon previous such work carried out primarily on materials from African sites (e.g., Kandel and Conard, 2005;Orton, 2008;Miller and Willoughby, 2014;Collins and Steele, 2017;Werner and Miller, 2018;Craig et al, 2020).…”

Victoria Cabrera Site: A Middle Stone Age site at Olduvai Gorge, Tanzania

“…Cortical surfaces were evaluated and analyzed, and as a result numerous types of modifications such as tooth marks, trampling, polished, fissures and rounding were identified (Behrensmeyer, 1978, Binford, 1981, Capaldo, 1998, Fernández-Jalvo and Andrews, 2003, Domínguez-Rodrigo et al, 2009, Pickering and Egeland, 2006. The description and quantification of the ostrich eggshells follows the criteria stated by Collins and Steele (2017) for the study of OES flakes. 3.3.…”