A small stream once ran through an Ethiopian gully 700,000 years ago. Footprints preserved in the sediment reveal many animals travelled alongside it, including birds, hippos, and gazelle1.
However, one set of tracks is particularly interesting. It turns out there a family of Homo heidelbergensis, including children as young as 1 years old, also travelled this route1.
They were the dominant human species of the period, and likely our ancestors2. As you might expect, this means they shared some similarities with us, such as enjoying a family day out. However, this set of footprints also highlights some key differences between our species, particularly amongst children.
The site in question comes from the upper part of the Awash Valley in Ethiopia1, carved by the Awash river. This area of the world has already earnt some human evolution fame, as the lower part of the valley is where Lucy was discovered. This earnt it a place on the UNESCO world heritage list.
So it’s nice to see the upper valley also getting some archaeological love, wouldn’t want it feeling left out.
The footprints themselves come from a part of the valley called the “Gombore Gully”, from which the footprint site’s creative name stems – Gombore II. The site was first discovered in 1965, and since then more than 5 metres of sediment have been excavated across several dozen square metres3. No wonder it’s taken us so long to study!
One layer of this sediment revealed a massive stretch of footprints. These were sandwiched by datable sediments above and below, indicating they were deposited in the interim around 700,000 years ago.
These tracks appear to have been quickly buried, which would normally lead to excellent preservation. Not in this case I’m afraid. Several animals returned to the site later, damaging any buried footprints. The hippo tracks above highlight an extreme example of this, not just damaging underlying footprints but pushing through deep into lower layers3.
The result is that any sequence of footsteps for a specific animal was annihilated. However, a few individual footprints remained for each. Some of these revealed a group of early humans travelling through the area1.
Based on the age of these footprints and the stone tools recovered from the site, it was inferred they were made by Homo heidelbergensis1. This species appears to have been the last common ancestor between us and Neanderthals2.
Given the quick burial of the footprints, they likely represent a very short period of activity for these early humans1, possibly even a single day. So what was a day trip like in the time of Homo heidelbergensis?
Well, it was busy. They made stone tools at this site, then used them to butcher a hippo carcase. In fact, they may have even killed that hippo. It does have carnivore damage, but it overlays the butchery marks. This suggests the carnivores only gained access to it after the human were done with it.
Perhaps they sought out and hunted this hippo as punishment for stomping all over this archaeological site.
So far all of this seems normal. Modern hunter-gatherers will also gather around food sources, making new tools as needed4. So it seems that, despite being separated by close to a million years, much of Homo heidelbergensis life was similar to ours.
However, things differences emerge when you start looking at the smaller footprints.
Some of the early human footprints found at the site were very small, suggesting there were very young children at this butchery and tool making site. It’s hard to make precise age estimates from mangled footprints, but it seems that the kids responsible for these tracks may be as young as six months old1.
This is fascinating for two reasons.
First, it highlights a difference in behaviour between Homo heidelbergensis and us. Modern hunter-gatherer children don’t typically join a proper hunt until their much older. Part of this may stem from the kids’ primary caregivers, the mothers, don’t take part in the hunts5. The presence of young children on a Homo heidelbergensis hunt might imply that there wasn’t this division of labour amongst them, with hunting being something both males and females did.
The second is that it highlights a possible biological difference between us. Modern kids are a bit rubbish, so normally don’t start walking until after the age of these footprints. If these Homo heidelbergensis kids were actually walking – their parents could have just plopped them in the mud – then it would imply they were maturing faster than modern babies1.
Of course, these inferences are based on tracks that have since been trampled and damaged. As such, you need to take it with a few grains of salt.
Still, it’s a fascinating glimpse into the childhood of our ancestors. A childhood where you might have had to have started helping with chores much earlier in life. That hippo isn’t going to butcher itself!
- Altamura, F., Bennett, M.R., D’Août, K., Gaudzinski-Windheuser, S., Melis, R.T., Reynolds, S.C. and Mussi, M., 2018. Archaeology and ichnology at Gombore II-2, Melka Kunture, Ethiopia: everyday life of a mixed-age hominin group 700,000 years ago. Scientific reports, 8(1), p.2815.
- Stringer, C., 2016. The origin and evolution of Homo sapiens. Phil. Trans. R. Soc. B, 371(1698), p.20150237.
- Mussi, M., Altamura, F., Bonnefille, R., De Rita, D. and Melis, R.T., 2016. The environment of the Ethiopian highlands at the Mid Pleistocene Transition: Fauna, flora and hominins in the 850-700 ka sequence of Gombore II (Melka Kunture). Quaternary Science Reviews, 149, pp.259-268.
- O’Connell, J.F., Hawkes, K. and Blurton-Jones, N.G., 1992. Patterns in the distribution, site structure and assemblage composition of Hadza kill-butchering sites. Journal of Archaeological Science, 19(3), pp.319-345.
- MacDonald, K., 2007. Cross-cultural comparison of learning in human hunting. Human Nature, 18(4), pp.386-402.