LONDON, May 12: Scientists from 15 countries are calling for a better political response to the provision of water and energy to meet the challenge of feeding a world of 9 billion people within 30 years. The joint statement by some of the world’s leading science academies was issued on Thursday ahead of the G8 summit in the United States. It is part of the annual lobbying effort aimed at focusing the attention of world leaders on issues the scientific community regards as crucial. (agencies)