Wearing a toilet seat on his head, David Hu, associate professor of mechanical engineering and biology at Georgia Institute of Technology, walks away with his team’s Ig Nobel Prize in Physics. The team studied the time mammals need to empty their bladders and found that nearly all of them do that in about 21 seconds (plus or minus 13 seconds). The 25th Ig Nobel Prizes awards ceremony was held on Sept 17 at Harvard University. The annual prizes are meant to entertain and encourage global research and innovation.