Evolutionary biologists explore ancient books to retrieve DNA and protein samples and get biological information on animals and people in past times. The process is very delicate and difficult, especially since ancient books are kept in extremely safe conditions and no physical intervention on them is allowed.
At a symposium that took place in May, with biologists, librarians, medievalists and other specialists, the possibility to find traces leading to information about medieval life was discussed. According to biochemist Matthew Collins, medieval manuscripts are filled with biological information. Since he could not access the books to retrieve samples, as no library or collector would allow an intrusive examination, he had asked his postdoctoral fellow in York, Sarah Fiddyment to develop an a non-destructive method to extract ancient proteins from parchment. That is when they decided to use tiny fibres from the debris gathered when librarians clean rare manuscripts with the use of a polyvinyl chloride eraser. Collins’ lab examined the Gospel of Luke, a rare 12th century manuscript to define the kind of animal the white leather cover was made of, an investigation commissioned by book historian William Zachs who had possession of the book. With the use of the technique found by Fiddyment they found that the cover was made of the skin of roe deer and the strap from a larger deer species. They also found that not all pages were made of the same animal skin, some having been made of goat, a rare material used in less wealthy animals.
All this offers information about the animal skin and therefore the animals, since it seems some were not so easy to find or others were in stock. When the relevant scholars saw the analysis of the materials used to make the book they were surprised, as there was an unexpected interleaving of calf and sheep.
Evolutionary biologist Blair Hedges, who works at Temple University in Philadelphia, Pennsylvania, examined the Gospel of Luke at the Bodleian, by inserting a tiny brush in a microscopic hole to collect bookworm excrement for ancient DNA analysis. Then, Andrew Honey of the University of Oxford noticed the holes went all the way to the oak boards beneath the binding, an indication that furniture beetles laid eggs in the oak before the bookmaker bound the wood in leather. This could be the oldest example of wormholes and the new method might help researchers trace the evolution of the bookworms.
The same way studies can find traces from bookworms, the animals the skin of which was used, or even people who left microbes by using the books.
Other medieval manuscripts from the Bodleian were also examined during the symposium and another specimen with the use of the same materials at the same period. One example is the York Gospels, written around 990 CE. Again there was a surprise for specialists, as they found that many pages were made of calf aside from sheep. They could thus conclude that a disease affected older cows, and that’s why the skin of younger calves was used. They also found that 20% of the DNA extracted from the book came from humans.
The discovery led to a boost of the new research field opened, with Collins travelling around the world with EU and book owners’ funding to gather specimens from various books. Even researchers studying the Dead Sea Scrolls in Israel are examining the option of getting ancient DNA from the parchments.
But there needs to be some collaboration between biologists and humanities scientists on the handling of the books and information that can be retrieved so that the huge amount of data gathered will be narrowed down to the most useful and actually new ones.