Archeologically useful allergens

I found an intriguing pair of articles on the BBC recently that seemed to have a common theme: the usefulness of ancient allergens in archeological study. I grant you, the fact that they’re allergens is not mentioned in the articles, but to an allergy sufferer, that was what made the link for me and I now find it odd that both articles were up on the same day.

The first article was about using ancient pollen to find the origins of the various types of terra cotta soldiers at the Emperor’s tomb in Xi’an, China. I have had a fascination with the imperial tomb for a while, since I wrote a paper on Qin Shihuang during college, and then traveled to China, where I actually got to stand on top of the tomb itself, imagining what was inside.

But anyway, back to the article. The traces of pollen in the clay of the soldiers can be used to figure out where all the different figures were made. As the article states:

Soils from different regions contain distinct pollen “signatures”, reflecting variations in vegetation.

However, it may not be an entirely accurate technique, because:

…if the clay came from an area near a river or stream, it could contain pollen from many sources washed in by the water. And if the clay was from a very old source, it could preserve information about vegetation that existed long before the time of the terracotta army.