Stable isotope analysis of soft tissues from mummified human remains

Abstract

Mummies are faunal remains that include the preservation of soft tissues, such as skin, muscle, nails and hair as well as bone. These soft tissues are generally rich in collagen or keratin proteins and thus provide potentially suitable material for stable isotope studies. When preserved, such tissues can provide high-resolution information about the diet and migration of humans in the weeks and months before death. Hair, nails and soft tissue provide short-term (months) dietary information in contrast to bone which will represent 5–20 years of dietary history prior to death, depending on the bone analysed. Such high-resolution data can answer questions on the season of death, seasonality of food resources and the movement and relocation of people. This review begins with a summary of the most common isotope techniques (¹³C/¹²C, ¹⁵N/¹⁴N) and the tissues concerned, followed by an analysis of the key questions that have been addressed using these methods. Until relatively recently work has focused on bulk protein isotope analysis, but in the last 10 years this has been expanded to on-line compound-specific amino acid analysis and to a wider variety of isotopes (¹⁸O/¹⁶O, ²H/¹H and ³⁴S/³²S) and these applications are also discussed.

Keywords:

• Mummies
• Stable isotopes
• Soft tissues
• Hair
• Skin
• Nails

Acknowledgments

Thanks are expressed to my colleagues who have worked with me on mummified tissues over the years including Ryan Metcalfe, Jenefer Cockitt, Andrew Chamberlain, Walaa Baker, Hannah O'Regan, Sarah Elton, Carolyn Chenery, Jane Evans, Silvia Gonzalez and Nick Feldstead. Melanie Leng and two anonymous reviewers are thanked for their constructive comments.