Scientists have discovered 3,000-year-old bodies that they believe were assembled from several unrelated corpses.

Patrick Dieudonne Medieval burial ground and chapels in South Uist, Scotland, the island where the mummies were found.

They didn’t have bolts through their necks but, like Frankenstein, the mummies found off the west coast of Scotland a decade ago were assembled with body parts from assorted cadavers.

The 3,000-year-old mummies were unearthed in 2001, but scientists only recently published their findings that the bodies were made up of several, maternally unrelated corpses. After being submerged in a peat bog for preservation, the mummies were buried in the fetal position beneath a round house, where they were found by archaeologists, reports the L.A. Times. Upon examination, researchers were astonished to discover that one body’s jaw didn’t match its skull and that the other skeleton showed signs of arthritis on the vertebrae of the neck, but not on the rest of the spine. They eventually concluded that the skeletons were assembled from at least three different bodies, which were separated in age by hundreds of years.

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Scientists believe that the bodies were assembled and tightly wrapped before mummification—possibly to symbocially unite several different lineages into one ancestry—and then buried up to 600 years after death. The body of a teenager and a 3-year-old child were also found buried with the composite skeletons.

“Altogether, these results have completely changed our ideas about treatment of the dead in prehistoric Britain,” researcher Michael Parker-Pearson told LiveScience.com.

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