for National Geographic News
Through the ages, ancient texts have survived wars, fires, theft, and neglect.
But so far scholars have only been able to draw upon anecdotal evidence to estimate how many handwritten texts created before the advent of the printing press in the 15th century have survived.
A new study, however, uses population biology to calculate the likelihood that an ancient text has survived from the eighth or ninth century to the present.
"The basis of the model is that manuscripts are like organisms," said John L. Cisne, a paleontologist and evolutionary biologist at Cornell University in Ithaca, New York. "A manuscript is going to behave just like an individual in a population. It can divide and reproduce or it can die."
Cisne's calculations may help historians to better establish the quantity of knowledge and science that we have inherited from antiquity and the Middle Ages. Cisne's study suggests that certain works have a greater chance of survival than has been guessed from anecdotal evidence.
The research is published in the current issue of the journal Science.
Turbulent times such as the Viking invasions, the Reformation, and the French Revolution, claimed untold numbers of medieval manuscript copies of ancient texts. The percentage that escaped has intrigued manuscript scholars for decades.
The late Bernhard Bischoff, considered the foremost authority on medieval paleography (the study of old writings and inscriptions), estimated that one in seven manuscripts produced during the reign of European king Charlemagne and his heirs (780-810 A.D.) has survived to the modern era.
"That's a really well-educated guess," Cisne said. "[Bischoff] based it on an encyclopedic knowledge of all the manuscripts of early medieval Europe."
But instead of examining the Latin manuscripts themselvesa painstaking and training-intensive process performed by paleographers and codicologists (a sort of manuscript archaeologist)Cisne suggests that equations from population biology can be used to estimate a text's likelihood of survival.
Cisne treated handwritten copies of ancient texts like fossils from an extinct population. He studied the Saint Bede the Venerable's De Temporum Ratione (A.D. 725), a standard early medieval textbook on arithmetic and calendar calculations. Popular from the 8th to the 16th century, the text's finger-counting chapter for years served as an instruction manual for low-tech "pocket calculators."
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