MIGRATIONAL PLASTICITY. “A strong evolutionary reduction of migratory activity has been observed in a blackcap population, presumably in response to climate change. These results suggest that the evolution of migratory behaviour in a resident population or of residency in a migratory population may be a common and rapid process.”
http://rspb.royalsocietypublishing.org/content/early/2011/02/11/rspb.2010.2567