This article (minus the pictures) was blatantly plagerized from Sir David Attenborough's Stumbleupon website. I tried to to capture in order to give credit, but couldn't ... on Stumbleupon (which I dearly love) they neglect to provide the web address.

Are you all completely bored stiff reading about corvids yet? Sorry, I can't help myself.

The scene: a traffic light crossing
Carrion crows and humans line up patiently, waiting for the traffic to halt.

When the lights change, the birds hop in front of the cars and place walnuts, which they picked from the adjoining trees, on the road. After the lights turn green again, the birds fly away and vehicles drive over the nuts, cracking them open. Finally, when it’s time to cross again, the crows join the pedestrians and pick up their meal.

A Japanese carrion crow examines the fruit of its labors.

If the cars miss the nuts, the birds sometimes hop back and put them somewhere else on the road. Or they sit on electricity wires and drop them in front of vehicles.

Biologists already knew the corvid family–it includes crows, ravens, rooks, magpies and jackdaws–to be among the smartest of all birds. But this remarkable piece of behavior–it features in the final program of “Life of Birds”–would seem to be a particularly acute demonstration of bird intelligence.

The crows in Japan have only been cracking nuts this way since about 1990. They have since been seen doing it in California. Researchers believe they probably noticed cars driving over nuts fallen from a walnut tree overhanging a road. The crows already knew about dropping clams from a height on the seashore to break them open, but found this did not work for walnuts because of their soft green outer shell.

Other birds do this, although not with quite the same precision. In the Dardia Mountains of Greece, eagles can be seen carrying tortoises up to a great height and dropping them on to rocks below. The hapless Aeschylus (525-456 BC), a father of Greek tragic drama, is said to have met his end by this means.

A seer predicted he would die when a house fell on him, so the wary scribe departed for the hillsides, well away from any dwellings, where he believed he was safe. He wasn’t. An eagle is said to have mistaken Aeschylus’ bald pate for a stone, and dropped the creature in its “house” onto it.

Scientists have argued for decades over whether wild creatures, including birds, show genuine intelligence.

Some still consider the human mind to be unique, with animals capable of only the simplest mental processes. But a new generation of scientists believe that creatures, including birds, can solve problems by insight and even learn by example, as human children do. Birds can even talk in a meaningful way.

Some birds show

quite astonishing powers of recall. The Clarke’s nutcracker, a type of North American crow, may have the animal world's keenest memory.
It collects up to 30,000 pine seeds over three weeks in November, then carefully buries them for safe keeping across over an area of 200 square miles. Over the next eight months, it succeeds in retrieving over 90 percent of them, even when they are covered in feet of snow.



On the Pacific island of New Caledonia, the crows demonstrate a tool-making, and tool using, capability comparable to Palaeolithic man’s. Dr Gavin Hunt, a New Zealand biologist, spent three years observing the birds. He found that they used two different forms of hooked “tool” to pull grubs from deep within tree trunks.


Other birds and some primates have been seen to use objects to forage. But what is unusual here is that the crows also make their own tools. Using their beaks as scissors and snippers, they fashion hooks from twigs, and make barbed, serrated rakes or combs from stiff leathery leaves. And they don’t throw the tools away after one use–they carry them from one foraging place to another.

Some ravens certainly apply their intelligence for the good of the flock. In North America, they contact other ravens to tell them the location of a carcass. Ravens are specialized feeders on the carcasses of large mammals such as moose during the harsh winter months of North America. The birds roost together at night on a tree, arriving noisily from all directions shortly before sunset. The next morning, all the birds leave the roost as highly synchronized groups at dawn, giving a few noisy caws, followed by honking.

They may all be flying off in the direction taken by a bird, which had discovered a carcass the previous day. This bird leads the others to his food store, apparently sharing his prize finding with the rest of the flock.

Ravens share information about their findings of food carcasses because dead animals are patchily distributed and hard to find. Many eyes have a better chance of finding a carcass, and once one has been located, the information is pooled.

Although the carcass now has to be shared between more individuals, the heavy snowfall and risk of mammal scavengers taking the kill mean that a single bird or a small group could not eat it all alone anyway. Some are even believed to solicit help with the carving, by tipping off other predators, such as wolves, about the meat so they will rip it open and make it more accessible to the ravens.