Before revision: The report found that livestock's contribution to greenhouse gas emissions was greater than that of the global transportation sector ; this conclusion was criticized in 2010 by Frank Mitloehner of the University of California, Davis, who noted that the authors had not performed a similar life-cycle analysis for transportation, causing the relative contribution of animal agriculture to be overestimated .
After revision: The report found that livestock's contribution to greenhouse gas emissions was greater than that of the global transportation sector .