click here to investigate western Colorado.' align='left' /> But the new study suggests how extreme its impact can be. Cattle in western Colorado. Photograph: John P Kelly/Getty Images “The fact that over half of that water is going to cattle-feed crops just floored us,” Richter said. “We had to double and triple check to make sure we got the numbers right.” Lake Mead, in Arizona and Nevada, for example, hasn’t been full since 1983, and has fallen by almost two-thirds in the last 20 years alone. According to Richter’s analysis, almost 75% of that decline can be attributed to cattle-feed irrigation. In the Colorado River Basin as a whole, which services about 40 million people in seven states and is overtaxed to the point that it rarely ever reaches the ocean anymore, that number is 55%. It takes a lot of water to make a double-cheeseburger. One calculation puts it at 450 gallons per quarter-pounder. The study also found that most of these water-intensive beef and dairy products are being consumed in western cities. “Beef consumers living in the Los Angeles, Portland, Denver and San Francisco metropolitan areas bear the greatest responsibility for these hydrological and ecological impacts,” Richter and his colleagues reported.
Figure 1. Brain Mapping Downstream of AGRP or SFONOS1 Neurons (A) The three phases of motivated behavior. (B) Intersectional strategy for anatomical (HSV) and functional (Fos) polysynaptic mapping of circuits downstream of AGRP or SFONOS1 neurons. (C) Pipeline for data acquisition and registration to the Allen Institute Mouse Brain Reference Atlas. Scale bar: 1 mm. (D) Intersection of labeling from HSV or Fos mapping across AGRP groups and SFONOS1 groups. Inset: 8 brain regions in and around the PCG. Red: anatomical or functional intersections. Yellow: four-way intersections. Gray: not determined.