SAN FRANCISCO, CALIFORNIA—According to a report in The Guardian, analysis of surviving Neanderthal DNA in the modern human genome by epidemiologist John Capra of the University of California, San Francisco, suggests that some Neanderthal genes may help some modern humans to rise earlier in the morning and go to bed earlier in the evening. After identifying gene variants related to circadian rhythms in Neanderthals and modern humans, Capra and his colleagues analyzed data from UK Biobank, which holds genetic, health, and lifestyle information for some 500,000 people. The study found that many of the people in the sample carried the Neanderthal variant, and reported that they woke up early. This trait may have helped modern humans adapt to life in areas with shorter periods of daylight as they migrated out of Africa, Capra said. “At higher latitudes it is beneficial to have a clock that is more flexible and better able to change to match the variable seasonal light levels,” he explained. Read the original scholarly article about this research in Genome Biology and Evolution. For more on Neanderthal gene variants in modern populations, go to "Painful Past."