The animal mummification industry that thrived in ancient Egypt held a secret which was not revealed for almost 3,000 years: around a third of the carefully wrapped religious offerings are boneless - and, for the most part, empty.
Researchers from at Manchester Museum and the University of Manchester reached this conclusion following a study that looked at more than 800 animal mummies.
The project to scan every mummy of animal shapes, from cats and birds to crocodiles, is the largest of its kind. It will culminate with an exhibition opening at Manchester Museum on Thursday Oct. 8, 2015.
Animals Mummified by the Millions in Ancient Egypt
About a third of the X-rayed and CT scanned artifacts do in fact contain complete and remarkably well preserved animals. Another third contain partial remains. The rest is simply empty.
Highlighted in a BBC documentary, the "mummy scandal" was exposed as scan of beautifully crafted animal mummies showed linens padded out with various items.
"Basically, organic material such as mud, sticks and reeds, that would have been lying around the embalmers workshops, and also things like eggshells and feathers, which were associated with the animals, but aren't the animals themselves," Lidija McKnight, an Egyptologist from the University of Manchester, told the BBC.
Experts believe as many as 70 million animals were ritually slaughtered by the Egyptians to foster a huge mummification industry that even drove some species extinct. How Different Cultures Made Their Mummies
There were four kinds of animal mummies: pets that died of natural causes before their mummification and were buried with their owners; sacred beasts, worshiped and pampered in life, and buried in elaborate tombs at their death; animals serving as food for their owners in the afterlife; and religious offerings, which were the majority.
Having miserable, short lives, these poor animals were simply bred to become votive mummies - offered to the gods in a gesture similar to the way people light candles in churches today.
The practice began as early as 3,000 B.C. and reached its zenith from about 650 B.C. to 200 A.D., when millions of animals like dogs and cats were raised by temple priests and mummified. According to the researchers, there was an element of demand outstripping supply which may have accounted for some mummies not containing a complete animal.
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"There simply wouldn't have been enough to go round," McKnight told Discovery News.
"More importantly, the ancient Egyptians believed that a small fragment of bone or material associated with the animals or a sacred space contained sufficient importance to be offered as a gift to the gods," she added.
McKnight believes the procedure shouldn't be seen as a forgery or scam as the pilgrims likely knew they were not burying a fully mummified animal.
"It simply wouldn't have mattered what they contained as long as they were a suitable offering to the gods. Often the most beautifully wrapped mummies don't contain the animal remains themselves," she said.
Image: Empty ancient Egyptian animal mummy. Credit: Manchester Museum, the University of Manchester.