Scientific Reports, 2016 Jan 5;6:18989.
Air pollution is good for something …. if you are a pigeon racer. It seems that in northern China, homing pigeons fly home lots faster through polluted air.
The authors say it isn’t yet clear whether this is because the birds just want to get out of the area faster (officially, they have “enhanced homing motivation”) or whether the increased amount of smelly stuff in the air helps them create an “olfactory map” that can help them find their way.