YOU learn something every day, so they say.

I'm sure that's true, although Mother Nature, always a keen believer in equilibrium, tends to balance things out by making sure we forget a few things along the way. That's my excuse for failing to remember my niece's 18th birthday at the weekend - the fact that my jaded bonce was required to absorb a piece of new knowledge. This time it concerned a pantomime villain of the bird world, that avian Captain Hook, the magpie.

Technically, I suppose, this wasn't a new entry in the databank; it was merely updating an erroneous item. It turns out that contrary to popular belief, magpies don't steal trinkets.

As we learned in The Herald on Saturday, tests carried out by Exeter University have shown that far from being attracted to shiny objects, they tend to avoid them. It's largely down to the fact that the poor things have neophobia - a fear of new things. Well, snap.

Of course, the magpie myth is not the only one to have been debunked recently. Take the one about goldfish only having a three-second memory, for example. Experiments by scientists at the Technion Institute of Technology in Israel, who trained fish to associate a sound played through a loudspeaker with feeding time, found that they remembered the sound five months later. This is good news for any 18-year-old goldfish out there, who can surely expect birthday cards from their uncles.

Similarly, it's not true that the Great Wall of China is the only man-made object you can see from space; in fact, when China's first astronaut, Yang Liwei, went into space in 2003, he said he couldn't see it from his capsule window, certainly not with the naked eye. You can, however, see the Great Pyramids of Giza, the Kennecot Copper Mine in Utah, and Sir Cliff Richard's penthouse flat (this last is an assumption, since you could see it from everywhere else at the weekend).

And don't believe that old chestnut about elephants being the only mammal that cannot jump. If jumping is defined as having all your feet in the air after being in a standing position, Jumbo is not unique; that distinction is shared by the sloth, the rhino, the hippopotamus and at least three Hibernian centre-forwards of my unhappy acquaintance.

One more myth blown apart concerns Bonaparte: Napoleon wasn't short. At 5ft 7in, he was taller than the average man of his time. It so happens that at 5ft 3in, I'm not short, either; it's just that I was born about 200 years too late. Fact.