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A grave unearthed in 1960 led researchers to hypothesize that Neanderthals interred their dead with flowers — challenging the prevailing view that the ancient humans were dumb and brutish. Now scientists say a key piece of evidence from the site, which helped shape the study of Neanderthals, might have been misinterpreted.
Archaeologist Ralph Solecki discovered the flower burial, as it came to be known, while exploring Shanidar Cave in the Kurdistan region of northern Iraq. He found several Neanderthal specimens in the 1950s, and in 1960, he identified a male skeleton that became known as Shanidar 4. The 65,000-year-old remains were surrounded by clumps of pollen.
Arlette Leroi-Gourhan, an archaeologist and expert on pollen, hypothesized at the time that these clumps were anthers, the pollen-containing structures in flowers. She and Solecki proposed that Neanderthals had laid flowers on the grave, in much the same way that many humans do today.
“You will find that story in many archaeology textbooks to this day,” said Chris Hunt, a professor emeritus at Liverpool John Moores University in the United Kingdom and lead author of a new study on the Shanidar site. “It was one of the things that persuaded Solecki that Neanderthals weren’t just nasty and brutish, which was basically what people had thought up to that point. But actually, they were caring individuals, and they looked after each other.”
Over the years, scientists found further evidence of Neanderthals’ intelligence and complexity, including art, string, and tools. However, elements of the flower burial theory didn’t seem to add up.
Hunt and his colleagues were working in the Shanidar Cave in 2014 when they found traces of ancient pollen on the surface of the cave floor. If it had arrived in Neanderthal bouquets, it would have been under thousands of years’ worth of sediment and debris, just like the Neanderthal skeletons.
“That was, for us, an indication that maybe there was something going on with the flower burial,” Hunt said.
The new study published in the Journal of Archaeological Science puts forth an alternative hypothesis: Instead of arriving to the cave via funerary bouquets, the pollen might have hitched a ride with cave-dwelling pollinators.
The bee theory
Hunt said he initially assumed the traces were remnants of the decades-old excavation.
“My immediate thought was actually that Solecki had contaminated the site,” perhaps carrying pollen in on his shoes decades ago, Hunt said.
Analysis of the pollen showed that it was thousands of years old, so it wasn’t a modern contaminant. But the finding established the idea that pollen had been making its way into the cave independent of humans or Neanderthals.
Further exploration of the pollen clumps found alongside the skeletons cast more doubt on the original hypothesis. Some of the pollen came from flowers that bloom at different times of the year, making it hard to see how they could have arrived together. And when Hunt examined Leroi-Gourhan’s illustrations of the pollen found with Shanidar 4, he saw that one of the clumps contained pollen from more than one species of plant.
“That is a red flag,” he said, because a flower’s anther only contains pollen from that species. Even if two different kinds of flower were in the same bouquet, it wouldn’t make sense for the pollen of two different species of flowers to be so closely stuck together.
However, there is an easy way for pollen grains from different kinds of flowers to get stuck together: bees.
“There are plenty of accounts of bees foraging or more than one species,” Hunt said. “What the bee does is pack the pollen into a little bag that it carries on its legs. Those go back to the nest, and they’re either eaten by the bees or they’re put away for foods for the future.”
Hunt found examples of both ancient and modern burrows in Shanidar made by ground-nesting bees. While he and his colleagues have yet to find traces of pollen in those burrows, he said, “I still think it’s quite a likely method” of the pollen’s arrival near the Neanderthal graves.
Paul Pettitt, a professor of paleolithic archaeology at Durham University in the UK who was not involved with the new study, said, “it’s a piece of perfect science.”
“The big issue is why is all of the pollen comminuted and sort of squashed together into these little clusters,” Pettitt said. In his view, Hunt “seems to have really nailed it there, to show it was most likely of bees.”
While there’s no conclusive proof that the pollen arrived via bees, “this paper does make the original flower burial hypothesis very unlikely in the way that Solecki framed it,” said Fred Smith, a professor emeritus of anthropology and biological sciences at Illinois State University, who was not involved with the study. “And I do think that they have demonstrated by the flattening and the degeneration of the pollen that the pollen is ancient, it’s not been introduced by modern contamination.”
What the flower burial gets right
While Hunt and his colleagues’ work suggests that the flower burial hypothesis is incorrect, the recent work on Shanidar Cave Neanderthals supports the underlying message of the old theory: that Neanderthals treated their dead with care.
The cave itself seems to have carried some sort of meaning, since the skeletons in it were interred separately, years apart. “As far as I can see, they must have had stories in their groups about, ‘Well, this is what we did with Grandma, and now that young Joe has died, perhaps we should put him in the same place,’” Hunt said.
The skeletons in the cave share common orientations and positioning, indicating that there may have been some meaning associated with how they were laid to rest. Shanidar 4 and Shanidar Z, a more recent skeleton discovery published in 2020, were found near splintered pieces of wood; Hunt said he wonders if those might have been from branches laid over the bodies to protect them.
In particular, Hunt said Shanidar Z was positioned as if she were sleeping.
“There was tenderness there. They cared for that individual, quite clearly,” he said. “Because why else would you do it?”