Entering the exhibition “Between Heaven & Earth: Birds In Ancient Egypt” at the Oriental Institute Museum, University of Chicago, you will immediately feel transported into the ancient Nile delta marshlands with its lush green flora.
The combination of colours, video footage, bird song and ancient artefacts gives the impression of travel through time and space. At the start of the exhibition, you will find one of their most impressive artefacts, an empty shell of an ostrich egg from 3100 BC. Ostrich eggs have not only been used in ancient Egypt as containers for liquids and raw material for bead carving, but also symbolize the deep integration of avian life into ancient Egypt’s spirituality. All life is at times described as entering and leaving the world through the egg as a vessel, and that birds are messengers that can travel between the realms of men and their gods. Many of the Egyptian gods are portrayed as birds, and even their people have been symbolized by different bird species.X-ray CT imaging
The information for the exhibition has been extracted from many sources such as ancient texts and drawings, exploration of burial sites, and with the help of X-ray CT imaging from mummified bird specimens. As shown impressively by Rozenn Bailleul-LeSuer, the reconstructed 3D X-ray images can be examined with Amira® 3D analysis software to extract the desired information and sometimes even discover surprises. Rozenn and her team of imaging scientists worked on several specimens.Small falcon mummy
The most impressive imaging results were obtained from a small falcon (see above, not on display at the exhibit due to space limitations). The falcon’s size and its missing wrappings allowed this specimen to be imaged in a micro-CT system at a resolution of approximately 180μm; more than 40 times higher than the clinical imaging system used for larger specimens. Using Amira’s advanced segmentation functionality and volume rendering, which allows masking of segmented regions in the visualization, the exact species of the falcon could be determined. Furthermore, it was shown that its neck had been severed, but that internal organs were still intact. The intestines had been pushed to the posterior of the bird to make room for a filled gizzard. The images also revealed the contents of the gizzard, which was identified as the remains of a small rodent from a piece of intact jaw bone.Juvenile Eurasian sparrow-hawk
CT images from another mummy revealed a small juvenile Eurasian sparrow-hawk. In this mummy, the wrappings were larger than required for a bird of this size. Missing bone calcification was evidence for the immaturity of the bird, and a posterior air pocket indicated penetration of insects that fed on the bird’s carcass. With this specimen, careful segmentation in Amira was the essential key for visualization of the mummy’s interior and identification of the bird. Here, the low calcification proved challenging during the segmentation process. Once the segmentation was completed, Amira’s crisp surface rendering allowed further analysis and identification.
A mummified juvenile sparrowhawk in its too large wrapping. The size of the mummy required image acquisition in a clinical CT, resulting in visualization of only coarse details. In addition the low bone calcification further reduces bone contrast. Image: Anna R. Ressman © Oriental Institute at the University of Chicago
Source: Visualization Sciences Group/authors: Rozenn Bailleul-LeSuer & Christian Wietholt
More Information
The Oriental Institute is open to the public without an admission fee. The exhibition is open until 28 July 2013.Additional information about this exhibit can be found at: http://oi.uchicago.edu/museum/special/birds
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