Advertisement

The fossilized poo of man, and man's best friend

You are what you eat - that's also true for humans and animals who walked the earth thousands of years ago.

Archaeologists have been excavating fossilized poop, also known as paleo-faeces or coprolite, to understand the health and diet of ancient man.

But researchers ran into a problem, says professor Christina Warinner from the Max Planck Institute for the Science of Human History:

(SOUNDBITE) (English) PROFESSOR CHRISTINA WARINNER, MAX PLANCK INSTITUTE FOR THE SCIENCE OF HUMAN HISTORY SAYING:

"Faeces tell an amazing story about people. It’s this extremely humble material but in terms of archaeology it’s a goldmine. But the issue here is we have to be able to distinguish the humans from the dog poop. And I think something that was really surprising to me is just how much dog poop there is in the archaeological record."

Professor Warinner and her team came up with a new tool to identify the origin of fossilized faeces - a system called coproID.

It uses machine learning to compare DNA analysis of ancient and modern faeces.

CoproID can then reliably predict the sources of poop, showing the combination of DNA and the distinct colonies of microbes living inside humans.

Dogs faeces can also be accurately distinguished.

(SOUNDBITE) (English) PROFESSOR CHRISTINA WARINNER, MAX PLANCK INSTITUTE FOR THE SCIENCE OF HUMAN HISTORY SAYING:

"I’m kind of imagining is just like people are cleaning up the dog poop in their back yard today, ancient people were also picking up the dog poop and throwing it into the garbage and so it all just sort of ends up in the same place and it can be really hard to tell where it originally came from and so that’s what originally gave us the idea to leverage the power of genomics to use DNA to distinguish the different faeces and this we’ve found to be really powerful.”

The team hope their research will help study changes in the human gut microbiome throughout time, which could explain a host of issues in human health.