Palaeodiet from Palaeofaeces

What?

Yes, you read that right, there is such a word as palaeofaeces. It's a word archaeologists sometimes use to refer to ancient human shit. It's pretty common knowledge that archaeologists work with human skeletons, so it's not that much weirder that they look at poop, right? Another word that is more commonly used is coprolite. Technically it means fossilised poop, and is the word for dinosaur poo that has turned to rock, cause it's like millions of years old. Ancient human poo isn't really old enough to be properly fossilized, but coprolite sounds much more polite than palaeofaeces doesn't it. Anyway, why I am posting about ancient poop? It's something I've talked about a lot over on my archaeology blog, and that's because it is probably one of the most useful things that we can examine in order to understand what people ate in the past. It can also tell us a lot about the gastro-intestinal health of ancient populations. So if we want to learn something about 'real' palaeodiets, it's a fun place to start.

What can you learn from ancient poo?

Just like a doctor can ask for a stool sample to check the health of your digestive tract, archaeologists can look as these little packages to get an idea of how healthy people were in the past, and what they were eating. Although a lot of the nutrients that you eat are absorbed by the body in the process of digestion, it's not a completely efficient process, and bits of the food and nutrients make their way through the body until they emerge at the other end, in an amorphous brown lump that we are all familiar with. This can include stuff you can see like fragments of bone, parasite eggs, bits of partially digested seeds and plant fibres, and also 'invisible' stuff, like chemical residues of fat and protein. We use pretty much the same tests that a doctor would to determine how much of this stuff is present, and where it came from. Unlike many of the other methods that archaeologists use to study ancient diets, looking at the stuff bundled up in a coprolite is a direct indicator of what someone was eating, over a very short period, probably a few days, along with an indication of their health. If the coprolite is well preserved, you can even slice it up into little bits to look at how the diet varied between each individual meal!

It's a bit like a detective game - not everything makes it's way through the digestive tract. Some stuff survives better than others (corn cobs anyone). So we have to be careful when we interpret the results. Ideally we look at lots of samples to get an idea of variations and whatnot. So finding ancient toilets is way more exciting than finding the next Stonehenge or some boring old precious metal object. If you're interested in palaeodiets anyway.

Next time...what sort of stuff do we know about palaeodiets that we learned from looking at palaeofaeces?

The famous Lloyds Bank turd - Viking coprolite