Eduardo Paes : More than half the world 's people now live in cities . Paes : Cities must be environmentally friendly , must find answers to congestion , pollution . Rio is using `` bus rapid transit '' as an alternative to building costly subway lines , he says . Our Olympic bid had to be selected over strong candidates such as Madrid , Tokyo and Chicago . Comment:
Eduardo Paes : More than half the world 's people now live in cities . Paes : Cities must be environmentally friendly , must find answers to congestion , pollution . Rio is using `` bus rapid transit '' as an alternative to building costly subway lines , he says . Comment: