WHAT would you name as the cleverest animals on the planet? Humans, obviously. Chimpanzees and the other great apes, too. What next? Dolphins, whales and dogs, perhaps. Maybe even rats. Well, now theres a new species to add to your list: the humble crow - or rather, its whole avian family, the corvids, which as well as crows includes ravens, rooks, magpies, jackdaws and jays. These unlikely brainboxes have been stealthily jumping up the animal IQ ladder for some time now. Indeed, in the past decade, scientists have made some startling discoveries that some crows could even be as intelligent as a human toddler. This week, the journal The Proceedings of the National Academy of Sciences published a report about a British rook that has been observed fashioning a piece of wire into a hook, which it then used to fish a small bucket of worms out of a plastic tube. A remarkable achievement for any animal. But this isnt the first time that rooks and their close relatives have demonstrated tool-making and tool-using abilities on a par with apes. In fact, rooks have demonstrated some quite spectacular feats of mental agility. In 1998, the BBC series Life Of Birds showed extraordinary footage in which a group of crows in Japan dropped nuts onto a road. Using passing cars to break open nuts is clever in itself - but what was particularly impressive, in this case, was the fact that the birds had picked a stretch of road at a pedestrian crossing. They would then wait for someone to press the button at the crossing, making the lights go red, before descending to collect their cracked nuts in safety. This demonstrates a clear comprehension of cause-and-effect, as well as an appreciation of a wholly alien (human) concept: traffic lights. Similarly, Science magazine reported in 2002 that a female New Caledonian Crow called Betty had, like the rook in the latest study, managed to work out how to fashion bits of wire into tools to retrieve food from a variety of hard-to-get-to places. What was really extraordinary was that the hooks made by Betty were constructed from flexible steel wire - not a material readily available in the birds natural habitat, a small Pacific island. And even more impressive still was how Betty made the hooks. Lacking hands, she had to first wedge one end of the wire against something solid, and then twist the other end at right angles with her beak. Now some animals do show a capacity to learn: but Betty had no prior training, nor had she watched another crow doing this. Instead, she had created her own complex solution to a new problem. Some chimps can make tools like this, but usually only after seeing humans or other chimps doing it first. Even some humans would struggle to come up with a solution as elegant as Bettys. Daily Mail Nor is this the limit to corvid intelligence: these birds also exhibit powerful 'social reasoning and excellent-memories. Several studies for example, have shown the extraordinary lengths to which they will go to protect food from their rivals. Many animal species hide their excess food, often by burying it in the ground. But, perhaps because they are notorious thieves themselves, rooks and crows (rooks are slightly smaller and have a patch of bare skin in front of the eyes) are also clever enough to know when they have been seen burying their food by a potential thief. If they think they have been spotted, they will quickly dig it up and hide it elsewhere. Cleverest of all, to throw rivals off the scent, some jays will even pretend to hide food by picking at the ground, before burying it elsewhere. And there is more. Another recent study demonstrated that crows and rooks are extremely adept at 'reading human faces and eye movements - better, in fact, than dogs or even apes. The birds in the study hesitated before taking food that they could see was being watched by a human, but were much more likely to pounce if they detected a lack of concentration or interest. Indeed, I have personal anecdotal experience of corvid cleverness - and deviousness. A few summers back, while out on my evening jog around a local park, I was attacked by a large crow as I ran under a tree. I remember a lot of flapping, a great deal of angry squawking and plenty of pain as its beak jabbed into my skull. The wretched thing had actually drawn blood. Bad enough. But what was truly unsettling was that 24 hours later, during which time hundreds of people must have passed by the same tree, exactly the same thing happened to me. Same tree, same bird. But this time I was prepared, and carrying a stick. I batted the bird away, leaving it to watch me run past with an evil stare. Finally, on day three, I went to the same spot at exactly the same time. And from a distance of about 30 yards, I saw my avian enemy sitting on her perch. She saw me, flew over, but did not attack, satisfied to merely squawk loudly. Perhaps she was also intelligent enough to have learnt to avoid being hit by my stick. Daily Mail