Fast moving rotating objects can register in the brain as a blur. This is what happens when you look at the blades of a rotating window fan. It creates what is known as a “brain or motion smear”. In other words, the blades become invisible. There has been great controversy recently about the use of wind power provided by turbines causing the death of a large number of birds. Birds have excellent peripheral vision but do not see as well when looking straight on. In a recent study performed at the Norwegian Institute for Natural Research it was discovered that painting one of the four blades black reduced the number of bird deaths by 72%. The study was conducted on the Norwegian island of Smola and was published in Ecology and Evolution. There were 8 turbines in the research. Half had one blade painted black. It lasted 7.5 years and there were 1,275 sniffing dogs involved. Their job was to sniff out any birds that may have died. The larger birds of prey seem to have benefited the most. Now what to do about the number one cause of bird demise by cats.