ORLANDO, FLORIDA—The number of births for the Kellis community living at Egypt’s Dakhleh Oasis 1,800 years ago probably peaked in March and April, indicating that most conceptions took place in July and August, during the annual flooding of the Nile River. “Even though this was a Christian community, we know that they were still practicing, or having these social beliefs of, fertility being at its highest in the months of July and August,” said Lana Williams of the University of Central Florida. Her team examined the well-preserved remains found in 765 graves, including remains of individuals who died between 18 and 45 weeks after conception. This information was combined with the month of death, determined from the position of the graves, which were oriented toward the rising sun. They found that the death rate of women of childbearing age and infants was greatest in March and April.