Could Egypt's empty animal mummies reveal an ancient scam?

(CNN)Tens of centuries ago, animals were increasingly seen as sacred representation of gods in ancient Egypt. Pilgrims would often pay for the mummification of an animal, in return for divine favor or revelation. And so a lucrative industry began (made up of animal keepers, embalmers, priests, and laborers building the cemeteries and catacombs) and, over time, up to 70 million animals were carefully preserved -- or so Ancient Egyptians thought.

Now, 3,000 years later, researchers in England have uncovered what by modern standards appears to be a scam of epic proportions. Using the latest medical imaging technology, radiographers and Egyptologists have scanned hundreds of animal mummies and found a considerable number contain only partial animal remains or are completely empty.
The researchers from Manchester Museum and the University of Manchester used a CT scanner and X-ray machine that would normally be used on children, to see beneath the wrappings without damaging the ancient specimens inside. On their findings, Lidija McKnight, who led the team, says: "We always knew that not all animal mummies contained what we expected them to contain, but we found around a third don't contain any animal material at all -- so no skeletal remains."
    To explain the phenomenon McKnight told the BBC that even the smallest parts of the animal may have been considered sacred and worth the effort of embalming. "We don't think it's forgery or fakery. It's just that they were using everything they could find."

    'Genre of fake mummies'

    Indeed the scale of animal mummification was so huge that other experts suggest that the use of fakes would have become inevitable.
    According to professor Selima Ikram, who in 2011 helped curate an exhibition of animal mummies at the National Museum of Natural History in Washington DC, baboons were mummified into near extinction.
    "If you wanted to have a baboon as an offering, you make it look like a baboon -- and if you say it is a baboon, then it magically becomes a baboon. The real ones were very expensive and hard to come by and that's why the whole genre of fake mummies started."

    Modern myths and climate lessons

    McKnight corroborates this idea that the belief systems of ancient Egyptians made the use of fake mummies acceptable. "Today, we want to think that what we are buying is what we are getting. But the ancient Egyptians were different. They were buying a mummy as a representation of a god. They believed that whatever was inside could be transformed magically."
    But if the animal mummies do not reveal some ancient hoax, what does the discovery actually tell us? McKnight suggests that the research, (which has been the most comprehensive to date, bringing various museum collections and different types of animals together in one study), holds interesting lessons for those studying climate change in Africa.
    "There are lessons to be learned about what ancient Egypt was like. From the mummies we can presume that Egypt might have been greener. For example, there would have been water sources that attracted large colonies of the sacred ibis -- one of the most mummified birds," says McKnight.