In the 1980s archaeologists found a 400,000-year-old hominin bone in Sima de los Huesos, Spain. But the discoveries didn't stop there. By 1997 they had found more than 2,000 human fossils representing more than 30 individuals. Was this the worlds oldest grave 1?
At nearly twice the age of our species, this ancient grave is way older than we might expect the first burials to be. But surely such a large collection of remains had to be deliberate. After all, they clearly weren't living in the cave. No tools or other habitation signs were found2.
However, not all are convinced it was a grave. At the time the cave it was inaccessible except through a vertical "chimney" in the roof. This turned the cave into a deathtrap, with animals plummeting into the pit 3. AI suggests the humans may have been accidental victims.
But can we trust the robots?
Ruling out accident
We've known about Sima de los Huesos since the 80s. The archaeological investigations there are older than me! Despite all this research, we're still finding out new things about the cave. These discoveries have implications for the grave hypothesis.
The latest discovery at the site is how it formed. Researchers painstakingly examined each archaeological layer to figure out how it came to be, revealing there were 7 main phases of sediment formation 3.
The 6th is the one of interest to us as it contains most of the hominin fossils. This sediment appears to have been mud gradually seeping into the cave, burying the human remains in the cave. It was a fairly sedate process, causing little damage to the fossils 3.
The overlying 7th deposit has a more dramatic history. This mud appears to have washed in from outside, perhaps during a flash flood or rainstorm, smothering the hominin layer in the process. As it came tumbling in, a few hominin fossils from the 6th layer got mixed in; but don't really belong there 3.
And that's the crucial fact. It turns out Hominin remains only really come from this 6th deposit. Conversely, the other animals, which likely fell in, are found in just about every deposit 3.
In other words, remains which wound up in the accidentally built up slowly, over a long period of time. The human remains are the opposite. Could this prove it was a deliberate burial?
But was it a grave?
All of this shows the site was formed by human choices. Something they decided to do meant there were a lot of human remains deposited, then it stopped. But that doesn't mean it was a grave.
Their choices may have been as utilitarian as "Hey, people keep falling down this hole. Let's move away and never come back". Or noting that prey was sparser in the area (perhaps because they were also falling down holes) and deciding to move on.
Even assuming people were deliberately chucking remains down the cave doesn't prove it was a grave. Some have pointed out how this seems almost careless and callous. Not the sort of care you might associate with a grave. So again, perhaps the choices were more utilitarian "this body stinks, let's throw it away" 2.
So we still have some work to do before we can determine if this cave is a grave. However, it does seem clear that it wasn't an accident either. Which, at the very least, is good for the reputation of these ancient humans.
We know they weren't blundering idiots who kept falling into holes.
References
- de Castro, J.M.B. and Nicolás, M.E., 1997. Palaeodemography of the Atapuerca-SH Middle Pleistocene hominid sample. Journal of Human Evolution, 33(2-3), pp.333-355.
- Stiner, M.C., 2017. Love and death in the Stone Age: What constitutes first evidence of mortuary treatment of the human body?. Biological Theory, 12(4), pp.248-261.
- Aranburu, A., Arsuaga, J.L. and Sala, N., 2017. The stratigraphy of the Sima de los Huesos (Atapuerca, Spain) and implications for the origin of the fossil hominin accumulation. Quaternary International, 433, pp.5-21.
