A visit to a zoo increases science and environment knowledge in children more than books or classroom teaching alone, UPI cited a British study as finding. In research conducted at the London Zoo, researchers from the University of Warwick tested more than 3,000 school children ages 7 to 14 about to visit the zoo on their knowledge of animals, habitat and conservation, then tested them again after their visit. The findings showed a 53 percent positive change in educational or conservation-related knowledge areas, personal concern for endangered species or desire to participate in conservation efforts, a university release said Friday. When zoo visits were augmented by an educational presentation by zoo staff, the increase in learning almost doubled compared with self-guided visits, the study found. "Globally, more than a tenth of the world's population passes through zoos annually so the potential is there to reach a huge audience," Warwick sociology Professor Eric Jensen said. "In recent years zoos have come under criticism for failing to demonstrate educational impact with certain lobbying groups arguing that it's cruel to keep animals captive," he said. "But zoos have been changing for years now to offer more educational and conservation information, 'behind the scenes' access for visitors, learning about habitat conservation work -- all of which culminate in a better engagement experience for the visitor." Children came away from their zoo visit with an increased understanding of ideas such as conservation, habitat and extinction, the study found. "The research clearly shows the valuable role that zoos can play in children's science learning," Jensen said.