The study by David Bryngelsson from Chalmers University of Technology in Sweden examined various future scenarios to determine how the climate would be impacted if humans were to change their diet. "Cattle ranching is already responsible for 15 per cent of the greenhouse gas emissions that humans cause," observed Bryngelsson, who recently presented his doctoral thesis on land use, food related greenhouse gas emissions, and climate change. He noted that increased consumption of beef runs counter to the goal of limiting the temperature increase to two degrees Celsius. There might be ethical objections to the current chicken industry, but Bryngelsson believes that climate gains will prevail even with more animal-friendly production methods. Technical improvements in the production chain can to a certain extent also reduce the food industry's climate impact, but cattle are still the biggest problem, he noted. It is difficult to change the fact that they need a lot of feed and that they release methane as they ruminate. Furthermore, forests are being encroached upon to make room for the increasing number of cattle, which also impacts the climate, the study pointed out. "Since around 70 per cent of all agricultural land is currently used to raise cattle, converting to a more energy-efficient diet of poultry would free up land for cultivation of for example bioenergy," Bryngelsson explained. "You could say that chicken is like an electrical car -- it is a better alternative, yet still very similar to what we are accustomed to," he said. How large a space domesticated poultry has to move around in does not impact greenhouse gas emissions to any great extent -- rather, the issue pertains more to cost. For example, if chickens are given a space that is five times larger, the space is still small in relation to the space required for feed production and will probably not noticeably affect the chickens' impact on the environment. The difference between chicken and beef as regards area requirements and greenhouse gas emissions is so great that there is no doubt that the chicken leaves a smaller carbon footprint regardless of production method, the study noted.