More than seven millennia ago, Stone Age mourners in what is now Sweden buried a boy with a crown of woodpecker feathers and, in another grave, interred a woman with multicolored fur-and-feather footwear, a new study finds.
These details were unearthed thanks to a newly developed technique that can identify traces of hair and feathers in soil taken from ancient graves, the researchers said.
"In general, fur, plant fibres and other soft organic materials have been recovered only under specific conditions, such as in underwater sites or in glaciers," Tuija Kirkinen, an archaeologist at the University of Helsinki, said in a statement. "With our method, it is possible to find microscopic fibres even in areas with poor preservation conditions."
In the study, published Feb. 20 in the journal Archaeological and Anthropological Sciences, Kirkinen and colleagues detailed the evidence of perishable materials that they found in 35 burials at Skateholm, a Late Mesolithic archaeological site in southern Sweden near the Baltic Sea coast that hunter-gatherer groups used as a cemetery from 5200 to 4800 B.C.
The researchers analyzed a total of 139 soil samples taken from the Skateholm graves. First, they identified fragments of bone, flint, charcoal and seeds in the soil. Then, they sieved and centrifuged the samples and looked at the remaining microparticles — fibers, hair and feathers — under a microscope.
Mammalian hairs were recovered from 20 graves, but only 25% of them could be matched to a type of animal, including otters, deer and cows. In one grave, however, the researchers found evidence of hairs from a lagomorph (mountain hare), a mustelid (weasel or stout), a bat and an owl, all recovered from the head area of a young adult male burial. Beads made from red-deer teeth that were also recovered from the head area suggest the young man was buried with decorative headgear.
From the analysis, the researchers concluded that at least 21 people were buried with feathers, many from species of waterfowl. Several of the feather particles were found in soil taken from the deceased individuals' head-and-neck area, suggesting they might have been used in headdresses.
In one grave, excavators found the skeleton of a child and an adult male buried with brown-bear teeth, amber beads, bone and stone tools, and red ocher. A soil sample taken from the space between them contained one deer hair and a possible woodpecker feather. These microparticles suggest that the child may have been wearing a deerskin garment and a headdress featuring woodpecker feathers.
And in the grave of an older woman, soil samples from around her neck revealed waterfowl feathers that likely made up a headdress or feather-fringed cape. At her right heel, soil samples produced a white hair from a weasel or stoat and a brown hair from a carnivore, suggesting she had been dressed in multicolored footwear that disintegrated over the centuries.
"The study underlines the significance of birds and their feathers, and it produces fascinating new knowledge," study co-author Kristiina Mannermaa, an archaeologist at the University of Helsinki, said in the statement.
Although the new technique works well, Kirkinen said, "species-level identification of microscopic feather and hair fragments is difficult, and this aspect of the analysis method can still be developed further."
Future research may involve analyzing more recently collected soil samples and using sediment DNA analysis to increase the likelihood of finding soft organic remains, the researchers concluded.
