Washington, February 5 (ANI): A new study found that male Eurasian Jays in committed relationships have the ability to share food with their female partner according to her current desire.
The behaviour suggests the potential for 'state-attribution' in these birds - the ability to recognise and understand the internal life and psychological states of others.
The research was carried out in Professor Nicola Clayton's Comparative Cognition lab at Cambridge University's Department of Psychology.
Researchers tested mated jays and separated males from females. The females were fed one particular larvae, either wax moth or mealworm - a treat for the birds, like chocolates - allowing the males to observe from an adjacent compartment through a transparent window.
Once the pairs were reintroduced and the option of both larvae was presented, the males would choose to feed their partner the other type of larvae, to which she hadn't previously had access - a change in diet welcomed by the female.
Through different tests using variations on food and visual access to the females during feeding, the researchers showed that the males needed to actually see the females eating enough of and become sated by one type of larvae - called 'specific satiety' - to know to offer them the other type once reunited.
This demonstrates that the males' sharing pattern was not a response to their partner's behaviour indicating her preference but a response to the change in her internal state.
"Our results raise the possibility that these birds may be capable of ascribing desire to their mates - acknowledging an 'internal life' in others like that of their own," said Ljerka Ostojic, who led the research.
When there was no opportunity to feed the female, males chose between the two foods according to their own desires. Only when they could share with the female did they disengage from their own desires and select food the female wanted.
The researchers believe that this ability to respond to another's internal state in a cooperative situation might be important for species living in long-term relationships.
Food-sharing is an important courtship behaviour for the Jays - so the ability to determine which food is currently desired by his partner might increase the male's value as a mate.
The research has been published in the journal PNAS. (ANI)