Chimps are our closest living relatives, but just how similar are we really? How much can they tell us about our ancestors? That’s the interesting question from Neanderthal-phile. I would like to believe that’s there real name and there’s someone out there who loves Neanderthals just so much.
Does this mean that human-chimp comparisons are relevent and useful again?
This isn’t just a problem when studying chimps though; it also applies to hunter-gatherers. Can we use them as analogies for our more recent ancestors, given they seem to have a similar lifestyle? Or is each culture so unique (and there’s has been influenced by the modern world) that such comparisons are invalid?
Unfortunately there’s no real answer to these questions. If we could prove that a particular animal was very similar to our ancestors we could just go study them. Then we’d have this whole “human evolution” thing sorted in an afternoon. Does this mean that studying chimps and hunter-gatherers isn’t useful? No; I think there are two scenarios in which they can be a great help to our understanding of the past.
Top down research
Physics has laws. Maths has laws. What about our behaviour? Are there certain universals about how people and/or primates behave. Because if we could identify those laws we can apply to them to our ancestors and learn an awful lot about them. That’s the principle of top down research. If we can study a huge range of chimps or hunter-gatherers certain trends might become apparent. Those trends would surely also be present in our ancestors.
There are many examples of this working well, with my two favourite examples being:
- The social brain hypothesis examined several primate species. This revealed that there is a correlation between brain size and group size, suggesting sociality influenced the evolution of our brains.
- Studying hunter-gatherers revealed a correlation between how hard it was to gather food and the complexity of the technology. In risky environments, people make more elaborate tools to mitigate that risk.
Based on that, we could infer that early humans living in risky environments (like the ice age) were probably making fancier tools than those who weren’t. And that our earlier ancestors were probably very social animals. And where we can test these predictions, they do hold true. The Solutrean is one of the most elabourate and fanciest toolkits made during the stone age. And it was made by people trying to survive the ice age.
Bottom up research
If top down research tries to identify universal truths about all humans; bottom up research is the opposite. Instead it tries to draw analogies between specific groups based on their similarities. For example, you might compare Savannah chimps to our early ancestors living in a similar environment. Or the Inuit to people living in the ice age.
You aren’t trying to uncover universal truths about all humans, simply note that in one situation something happened; so it might have happened in other similar situations in the past. The key to this sort of research is just how similar those situations are. There’s all sorts of complex criteria you could use, with the more boxes being ticked the more reliable your conclusion.
- Are they as smart?
- How similar is the environment?
- What sort of resources do they have access to?
- Is predation risk similar?
- What about risk of resource failure?
- Is population density comparable?
The list goes on and on.
And much like top down research, this does have some success stories. Savannah chimps live in a similar locale to some of our early ancestors. And they have a similar sized brain as those ancestors. So many assumed they would have similar technological capacity. And lo’ we recently found that they were making very similar tools.
The bad research
So whilst I would say studies of chimps and hunter-gatherers can be very useful I’ll be the first to admit there are some bad examples out there. I think a lot of these stem from when people conflate the two types of research. They try and draw a universal rule from a group that is analagous, but not large enough to make such rules from.
But nevertheless, in the right context we can trust chimps to tell us about our past.