Source: Nature: "Ravens"
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Ravens demonstrate several of the commonly accepted indicators of animal intelligence. Some of these indicators can best be observed when ravens are scavenging for food. In this video segment from Nature, ravens exhibit their bird brain power by counting and hiding their food.
Transcript (Document)
The traditional view of birds was that they simply acted by a set of inherited instincts, but new scientific research is revealing a larger role for complex cognitive processes in their behavior, including communication, counting, memory, and basic problem solving. Ravens, known as the brainiest of all birds, demonstrate several of these commonly accepted indicators of animal intelligence.
In the depths of winter in Ely, Minnesota, ravens are taking advantage of another animal. Us.
A place like this is raven heaven.
When trash is left out for collection the big black birds descend, helping themselves to choice leftovers.
But even a trash raid requires some strategy. This raven knows it can carry four hot dogs at once - so it counts them out.
But in this town, they don't even need to scavenge - it's a local tradition in Ely to feed the ravens.
Whenever so many ravens come together, they have to have a social structure to communicate with each other. They use a complicated language of different sounds. Body language is also important - between ravens, different postures mean different things.
John Marzluff: A good example of the posturing involves the throat feathers, and the head feathers will pop up in what we call ears. In an adult territorial bird, these feathers stay right in the side of their head and that's a very aggressive posture...they do that...their throat feathers come out, their pants go down, as they let the feathers around their legs get very bushy. It makes them look big. It makes them look certainly more formidable.
Ravens are quick, sociable, ingenious, intelligent. And they get the most out of the company of others. Birds, mammals, and especially humans – ravens have learned to use other creature's skills to their own advantage.
Ravens even do a little planning for the future.
A dead hare is more than enough for one raven, and it can't eat it all at once – although it tries its best.
The word ravenous says it all.
But once it's eaten its fill – it’s so heavy it can hardly take off – it carries the rest of the food away to hide.
Now it must find good hiding places and remember where they are.
Hiding food for future use - a behavior called 'caching' - is a good way to protect against uncertain food supplies.
That is unless another raven is watching. When the rightful owner leaves, this raven just helps itself.
There's no honor among these thieves.