Mummified monkey
A 3,500-4,000-year old mummified monkey is seen on display in the Egyptian Museum. Reuters

Academics lift the lid on a scandal involving ancient Egyptian mummified animals in which a third of the mummies examined were empty.

The discovery was made when scientists at the University of Manchester and Manchester Museum began a scanning project to examine the contents of their mummified specimens.

Around 800 mummies including crocodiles, birds and cats were scanned using X-rays and CT scans, according to a BBC report.

"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," said Dr Lidija McKnight, an Egyptologist from the University of Manchester.

A third contained bits of animal remains and the rest were empty, filled with things like mud, eggshells and nest material instead.

"We think they were mummifying pieces of animals that were lying around, or materials associated with the animals during their lifetime - so nest material or eggshells," adds McKnight.

"They were special because they had been in close proximity with the animals - even though they weren't the animals themselves.

"So we don't think it's forgery or fakery. It's just that they were using everything they could find. And often the most beautifully wrapped mummies don't contain the animal remains themselves."

Demand outstretched supply as mummified animals were of great religious importance in Ancient Egypt, that the makers made do with alternative items instead.

"We know the Egyptians worshipped gods in animal forms, and an animal mummy allowed you some connection with the world of the gods, " explained Dr Campbell Price, curator of Egypt and Sudan, at Manchester Museum, which will have an exhibition on animal mummies in October.

"Animal mummies were votive gifts. Today you'd have a candle in a cathedral; in Egyptian times you would have an animal mummy.

"You would go to a special site, buy an animal mummy, using a system of barter. You'd then give it to a priest, who would collect a group of animal mummies and bury them."

Even today, antiquities are vital to Egypt's tourist trade but with the country in political turmoil in the three years since the Arab Spring, many ancient sites have been ransacked, with many thefts from museums.

Egyptian artefacts returned

In June, a collection of 32 ancient Egyptian artefacts will be brought back to Egypt after successfully asserting ownership of the objects.

Ali Ahmed, director of antiquities repatriation, told Ahram Online that the objects included limestone and wooden statues as well as a collection of limestone blocks from chapels across dfferent pharaonic periods.

The objects were seized by the Swiss police thanks to an agreement between Egypt and Switzerland that prohibits the illegal import and export of cultural properties.

Minister of Antiquities Mamdouh Eldamaty said the objects are to be handed over to Egypt's ambassador to Switzerland at the Federal Office for Culture in Bern during an event to mark the ten-year anniversary of the Swiss law which prohibits illegal trade in cultural property.