Rainfall patterns in the Sahara during the 6,000-year "Green Sahara" period have been pinpointed by analyzing marine sediments, according to new research led by a UA geoscientist.What is now the Sahara Desert was the home to hunter-gatherers who made their living off the animals and plants that lived in the region's savannahs and wooded grasslands 5,000 to 11,000 years ago.