todaysbird:

crows and ravens have demostrated a knowledge of ‘fairness’ – and demand equal treatment. researchers did an ‘inequity test’ on the birds. some birds received cheese, a high value treat, and others received a piece of grape, which was not desirable. those who received the grape started refusing to accept it. the researchers then performed an ‘effort control’ test. some birds were given a piece of cheese with nothing required of them. other birds could choose from cheese or a grape – but had to exchange a token for them. again, the birds that were being treated unfairly refused to cooperate.

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