Caws and Effect (AMA)

"Reddit, what have I gotten myself into?"

Alex Taylor takes your questions on Reddit (AMA)

After the warm response yesterday that Redditors gave Alex Taylor and colleagues paper, "New Caledonian crows reason about hidden causal agents", the social media website have invited him to participate in an 'Ask Me Anything' (AMA).

Get your crow cognition questions ready for Alex Taylor as he takes on Reddit /science/ in an AMA (Ask Me Anything) - Sept, 19, 23:00 GMT

Link: Reddit.com/r/science

Crows can 'reason' about causes, a recent study finds

Curious crow is curious

(BBC Nature, 18, Sept, 2012) - Tool-making crows have the ability to "reason", say scientists.

In an experiment, researchers found that crows were more likely to forage when they could attribute changes in their environment to a human presence.

This behaviour may suggest "complex cognition", according to a study published in the Proceedings of the National Academy of Sciences.  Until now the ability to make inferences based on causes has been attributed to humans but not animals.

The study was a collaboration between researchers from the University of Auckland, New Zealand, the University of Cambridge, UK and the University of Vienna, Austria.

In their experiment eight wild crows used tools to remove food from a box.  Inside the enclosure there was a stick and the crows were tested in two separate series of events that both involved the stick moving.

In one instance a human entered the hide and the stick moved. In the other, the stick still moved but no human entered.  On the occasions when no human was observed entering the hide, the crows abandoned their efforts to probe for food using a tool more frequently than they did when a human had been observed.

According to the scientists, the study proved that crows attributed the stick's movement to human presence.

The results indicated that neither age nor sex was a predictor of the behaviour with juveniles, males and females displaying the same behaviour.  Scientists said that the kind of "reasoned inference" shown by the New Caledonian crows under these controlled conditions could also be utilised in the wild to anticipate danger or food.

The study is the first to suggest that animals have the ability to make reasoned inferences, although scientists added that the phenomenon could be more common among animals than previously thought.

Journal reference: New Caledonian crows reason about hidden causal agents - http://www.pnas.org/content/early/2012/09/10/1208724109

Crows can remember and differentiate human faces

"I know I know you"
 - The Crow (1994)

(New Scientist, Sept, 10, 2012) - You can run from a crow that you've wronged, but you can't hide. Wild crows remember human faces in the same way that mammals do.

Crows can distinguish human faces and remember how different people treated them, says John Marzluff of the University of Washington in Seattle.

To work out how the crows process this information, Marzluff had members of his team wear a latex mask as they captured 12 wild American crows (Corvus brachyrhynchos). The crows learned to associate the captor's mask with this traumatic experience. While in captivity, the crows were fed and looked after by people wearing a different mask.

After four weeks, the researchers imaged the birds' brains while they were looking at either the captor or feeder mask. The brain patterns looked similar to those seen in mammals: the feeder sparked activity in areas involved in motivation and reward, whereas the captor stimulated regions associated with fear.

The result makes sense, says Kevin McGowan of Cornell Lab of Ornithology in Ithaca, New York. Crows don't mind if humans are in their habitat – but they need to keep a close eye on what we do.

Journal reference: Proceedings of the National Academy of Sciences, DOI: 10.1073/pnas.1206109109