The AP had a nice wire article today about new research on smelling and how the human nose works. Some researchers had college students sniff their way to chocolate through 30 feet of grass while blindfolded. Then they had them try it with one nostril plugged up, and with a tube over the nose so that both nostrils are getting the exact same airflow. The evidence revealed that the brain does actually treat signals from the nostrils separately, something that was thought to be impossible with our nostrils so close together, but the people using two nostrils did better than those with one.