Parrots can make complex economic decisions, at least according to German scientists.

33 macaws and African grey parrots were taught to recognise the value of tokens which could be exchanged for food as part of the experiment at the Max Planck Institute in Germany.

The birds then had to invest their tokens, either in low-value immediate rewards, or high-value but more expensive rewards.

The most patient parrots could exchange their tokens for pieces of walnut, while the less determined traders were stuck with dry corn or sunflower seeds.

Scientists found that when offered a low quality food or a token, the parrots would consistently choose the token if it could get them a better food prize.


Lead researcher Dr Auguste von Bayern, from the Max Planck Institute of Ornithology in Starnberg, Germany, said that because wild parrots are difficult to track it is hard to know whether these kind of decisions are a part of the parrots' natural life.

She said: "In our experimental setting we have found that they are capable of making surprisingly subtle decisions to maximise their payoff while minimising their effort.

"This is a fascinating indication that such decisions may matter greatly in their natural environment."

Nine great green macaws, eight blue-throated macaws, eight blue-headed macaws and eight African grey parrots took part in the study.

Von Bayern's team said the parrots had performed as well as chimpanzees being tested on the same parameters.

Overall, the great green macaws came out on top, making the right decisions significantly more often than expected by chance in every test.