Ravens can remember people who have tricked them

Ravens have long been said to posses impressive intelligence and it seems they also remember people who treat them unfairly. Researchers have found that the creatures could recall trainers who gave them a raw deal by stealing their food up to a month later. The findings add to a growing understanding of the highly intelligent behaviour demonstrated by the corvid family of birds, which includes crows, ravens, magpies and others. Researchers from the University of Vienna have found that ravens (pictured) can remember being conned by human trainers up to a month after they last had contact. A group of ravens were trained to trade chunks of bread for lumps of cheese.