Review and outlook: the role of UAs in transitions
Roles of urban agriculture in ecological transitions

Controversies allow us to move away from an overly positivist view of scientific activity, bringing out the artificial and conventional aspects of the practices and beliefs that accompany it (as with any activity). Arte, for example, reports that over 20% of the countryside has been nibbled away by Europe's metropolises since the early 1960s, raising the question: at this rate, filling our plates will be a feat. To survive, will city dwellers...