Is this shrunken head really human? Combining imaging methods provides cluesThank you for reading this post, don't forget to subscribe!
We rarely have time to write about every great science story we come across. So this year we’re running a special Twelve Days of Christmas series of posts again, highlighting a science story that fell through the cracks in 2020, every day from December 25th to January 5th. Today: Sophisticated imaging methods can be used to verify that shrunken heads (clean) in museum collections are original.
In Tim Burton’s 1993 animated film The Nightmare Before Christmasthere is a scene where a little boy gets a shrunken head as a Christmas present from Jack Skellington. It does not go well with the boy or his parents. But there was a time in the early 20th century when these macabre objects were so sought after by Western collectors that it spawned a lucrative market for fakes. Many museums around the world count shrunken heads (known as clean by Put people out) among their collections, but how can curators determine whether these items are authentic? Some sophisticated imaging methods can help, according to an August paper published in the journal PLoS One.
The practice of headhunting and making shrunken heads has been documented mostly in the northwestern parts of the Amazon rainforest, as well as among some tribes in Ecuador and Peru, such as the Shuar. The accounts contradict the specific details of the production process. But on clean usually created by removing the skin and flesh from the cranium of the skull through an incision at the back of the ear and then discarding the skull. The nostrils were filled with red seeds and the lips were sewn shut. The skin is then boiled in water infused with tannin-rich herbs for 15 minutes to two hours so that the fat and grease float to the top. It also caused the skin to shrink and thicken. The head was then dried with hot stones and shaped back into something resembling human features, and the eyes were sewn shut. As a final touch, the skin was rubbed with charcoal ashes—apparently to keep the vengeful soul from escaping—and sometimes beads, feathers, or other trinkets were added for decoration.
The traditionally finished ones tsantas were displayed on poles inside houses – not worn, according to the authors of the August report, despite what can be read in the existing anthropological literature. The shrunken heads were a popular collectible among Victorian-era priests, Europeans and American explorers eager to bring back exotic items for their private collections. Eventually a commercial market developed as the practice became more widely known after 1860. But these commercial clean they were often made from animal skins (usually pigs, monkeys, or sloths), although some were made from human heads collected from corpses in morgues. However, the manufacturers claim that their goods are original.
Lauren September Poeta of Western University in London, Ontario, and her coauthors estimate that up to 80 percent of clean currently held in collections around the world are of commercial origin and there are very few reliable methods capable of determining their true provenance. Curators typically rely on visual inspections or CT scans for authentication. But the Poet et al. note that four key features are poorly resolved using a standard CT scan: the sutures, eye anatomy, ear anatomy, and scalp anatomy. So they decided to see if they could improve the resolution of these features by combining CT scans with high-resolution micro-CT scans, an approach known as correlative tomography.
The team uses a clean from the collection of the Chatham-Kent Museum in Chatham, Ontario, acquired by the museum in the 1940s from a local family who purchased it while exploring the Amazon basin. The only note of origin was that it came from “Peruvian Indians” and there was no definitive proof that Chatham clean was the genuine article. The researchers took a clinical CT scan of the entire object and two micro-CT scans — one of the entire head, the other a high-resolution scan of part of the scalp — using a machine at the Ontario Museum of Archaeology.
The poet and her colleagues confirmed that Chatham clean was made from real human remains, although they cannot determine whether it was made ceremonially or commercially. The crude incision at the back of the skull and the use of double concealment are consistent with the former, but modern thread was used to sew up the incision, eyes and lips, suggesting commercial production. “In fact, it may be that the division between ceremonial and commercial production is more difficult to define than is commonly thought, since the practice of creating clean likely exists on a spectrum rather than an either/or dichotomy,” the authors write.
More can be learned through exposure clean of known origin for correlation tomography images. The authors conclude that while conventional CT scanning remains useful for reconstructing a basic visualization of these fascinating artifacts—allowing researchers to examine them closely without risking damage from repeated handling—micro-CT scanning can determine whether a given clean is made of human materials and provides higher resolution details for specific functions.
#shrunken #human #Combining #imaging #methods #clues