If you haven’t sent your Christmas cards by now then it may be too late.

Yesterday was the Royal Mail’s last posting day for guaranteed arrival before Christmas Day. So I sat writing all mine on Wednesday night, in a hurried attempt to meet the deadline.

There were two card designs among those I sent. Some had the three wise men on the front, all holding their presents of gold, frankincense and myrrh - suggesting that the commercialism of Christmas is nothing new, and started very early.

The other cards had robins on them, which is hardly surprising. Robin redbreasts are regularly voted Britain’s favourite bird, and are never more popular than at this time of year.

They remain in Britain for the full 12 months - not flying south to avoid our winters like many others - and they also sing almost all year round.

Aren’t they sweet, loyal and melodious, we’re meant to think.

I have an instinctive mistrust of anything that seems hugely popular, whether it’s The Great British Bake-Off , Strictly Come Dancing , Brexit, royal weddings, raindrops on roses or whiskers on kittens. And where I grew up brown paper packages tied up with strings were often suspected.

So allow me to dispel a couple of myths about Britain’s favourite bird.

For a start, the robin’s breast isn’t red at all but orange. The word “orange” didn’t exist in the English language until the 1500s, when the fruit of that colour was first introduced here. So when they named the bird, “red” was the nearest equivalent.

And robins are not as nice as they look or sound. In fact they’re hooligans.

I was once told of a rampaging robin that was forever attacking its reflection in the wing mirrors of a builder’s van.

Believing the reflection was another bird muscling in on its territory, the robin would spend much of its day flying at it or messing over the mirror.

The van’s owners got so aggravated that they once left its doors open, waited for the robin to fly in, and then drove 25 miles south before releasing it.

By the time they returned to the site the bird had already flown back, ready to do battle with its reflection again.

I asked an RSPB expert whether this was typical behaviour for a robin and was told that it was absolutely.

People think they’re cute Christmassy creatures, the expert explained, but in actual fact they are some of the most aggressively territorial birds we have, always quick to attack another bird, whether or not it's an intruder.

They generally come to realise that an image in a mirror isn’t a threat. This bird was either unusually aggressive or unusually stupid.

But all robins are violent. According to researchers, their year-round singing is a warning to other birds to keep off its patch.

I’ve never been a “cat person” and my feelings about them are rather mixed. I don’t like the way they kill garden birds but I’m quite happy for them to kill rats. I’m not a rat person either.

But it sounds like robins are just as ruthless as cats. They have razor-sharp claws and will lash out at other birds without provocation.

It’s other robins that the robin dislikes most - and when it sees another orange breast it sees red. Males will peck at the napes of other ones until they break their spinal cords, and 10 per cent of all the deaths of adult robins are inflicted by other robins.

They’ve even been known to attack mounted specimens of stuffed robins until the stuffed ones are destroyed. You could say they’ll kill another bird even if it’s already dead.

Yet despite the endemic robin-on-robin violence they aren’t as endangered as some of our other birds. The RSPB reckon there are more than six million breeding pairs of robins in the UK, while numbers of other once-common species like the house sparrow are in sharp decline. They’ve almost halved in the last 40 years and are down 60 per cent in towns and cities.

Dunnocks and gold finches are also in serious trouble. So are starlings - whatever their massive November gatherings in the skies over Gretna might seem to suggest.

I think we should choose another bird as our favourite, something gentler, one of those endangered ones that could do with the attention.

For next year’s cards I’m going to choose a partridge in a pear tree.