SOUTHWESTERN ENGLAND—Mesolithic hunter gatherers living in the Severn Estuary, at the mouth of the Severn, Wye, Usk, and Avon Rivers, used fire to encourage the growth of hazelnuts, crab apples, and raspberries. “Previously it was thought that these people were mainly hunting deer and simply responding to the spectacular environmental changes around them, such as sea level rise. Now there is increasing evidence that they were adept at manipulating their environment to increase valued plant resources,” said Martin Bell of the University of Reading. The researchers have also found ancient footprints left behind by animals, birds, and human adults and children.