(p. D3) Chalk up another achievement for parrots, . . . .
Anastasia Krasheninnikova and colleagues at the Max Planck Institute for Ornithology in Germany tested four species of parrots in an experiment that required trading tokens for food and recently reported their findings in the journal Scientific Reports.
. . .
A metal hoop could be traded for a piece of dry corn, the lowest value food, a metal bracket for a medium value sunflower seed and a plastic ring for the highest value food, a piece of shelled walnut.
The birds were then offered various choices, like a piece of corn or the ring. They all reliably chose to forgo the corn and take the ring. Then they were able to trade the ring for a piece of walnut.
They also did well choosing a bracket instead of the corn, and in other situations where the token was of higher value than the food.
For the full story see:
(Note: ellipses added.)
(Note: the online version of the story has the same date as the print version, and has the title “Parrots Think They’re So Smart. Now They’re Bartering Tokens for Food.” Where there is a small difference in wording between the versions, the passages quoted above follow the online version.)
The paper published in Scientific Reports and mentioned above is: