Whether you savour Ottolenghi’s recipes or prefer a feast from Nigella’s cookery books, humans enjoy mixing flavours and textures when preparing food. Now research suggests some cockatoos do too.
Researchers have previously discovered that some of the birds dunk dry rusks in water before eating them, just as some people enjoy dunking a biscuit in tea, apparently reflecting a penchant for a soggy texture.
Now they have found the birds also enjoy dipping pasta into blueberry soy yoghurt.
“The birds [in an experiment] had a problem that their food was not tasty enough, and so they went to the yoghurt, really dunked it in like we would do with fries and ketchup, and then they ate it together,” said Jeroen Zewald, first author of the research from the University of Veterinary Medicine in Vienna. “And if they ran out, they did it again.”
The team note the only previous work to suggest animals flavour their food was a study published in the 1960s in which Japanese macaques were found to dip potatoes in salt water.
Writing in the journal Current Biology, Zewald and his colleague Dr Alice Auersperg report how they initially noticed two captive Goffin’s cockatoos dunking cooked pieces of potato into blueberry soy yoghurt during breakfast.
The duo then carried out 14 trials, each lasting 30 minutes. During each trial, a group of 18 birds was presented with bowls of either pasta and cauliflower or potatoes and carrots alongside three dips: blueberry soy yoghurt, plain soy yoghurt and fresh water.
The birds did not dunk carrots or cauliflower into any of the dips. However, nine of the cockatoos tumbled pasta, potatoes or both into the soy yoghurt, preferring the blueberry flavour over the plain – a finding that suggests the behaviour was not just about texture. The cockatoos also preferred to directly eat the blueberry soy yoghurt rather than the plain option.
The team say it is unlikely the birds were dunking the food to make it soggy as the snacks were already soft, the birds did not dunk food in water, and the cockatoos only dunked food in soy yoghurt for about three seconds – as opposed to more than 20 seconds when previously observed dunking dry rusks in water.
Instead, they say the birds were probably dunking their food to flavour it, adding that further trials suggested the preference for blueberry soy yoghurt was not down to its colour.
The team said the birds were very vigorous in their dunking: dragging, rolling and pressing the food in the soy yoghurt – possibly to increase coverage.
“They ate the food and yoghurt together and never licked the yoghurt off before eating the food, indicating their preference for the combination of both food items,” the authors write.
Zewald said the behaviour appears to be a new innovation, although it is not clear if one bird taught others, or if it arose independently in different birds.
“You would expect that, if it was an innate behaviour, the entire group would show this behaviour, but we know that not all of them do this, and that in the wild, we also have not seen it,” he said.
Zewald added that the birds were particularly keen on dunking pasta in blueberry soy yoghurt
“I must say, I’ve tried it myself. I don’t know what they really like about it,” he said. “It is not a recommendation.”
