COPENHAGEN, DENMARK—Veterinary scientist Martin Søe of the University of Copenhagen led a team of researchers who examined excrement for evidence of diet and health in northern Europe between the early eleventh and eighteenth centuries, according to an NPR report. This new study offers a more detailed analysis than previous investigations of feces and parasites, and has created data that could fuel further research into pathogens and diseases. Most of the samples came from Denmark, the Netherlands, and Lithuania. The scientists filtered them through fine meshes to collect parasite eggs, and washed them to collect plant and animal DNA. The DNA sequences were then compared with known databases to identify what the people had eaten. Certain parasites, such as fish tapeworms, also offer clues to human diets. For example, in addition to fish tapeworms, Søe detected tapeworms associated with eating raw or undercooked pork in samples from seventeenth-century Denmark. Viking-era samples yielded fin whale DNA. Waste and parasites from cats, horses, rats, and mice were also detected in the samples. Søe thinks their waste may have been cleaned up from other locations and deposited in the toilets. For more, go to “Vikings, Worms, and Emphysema.”