Flight. To us earthbound human beings, it is the greatest miracle of them all. So much so that we keep trying to do it ourselves: by flawed means such as running, skiing, riding horses, bungee-jumping, even playing golf (making that ball fly off the tee ... ). Birds are the most studied and the most watched of all living things, because they can fly.

But when it comes to the greatest aeronauts of them all, in terms of agility, accuracy and control — creatures that we go so far as to name for their powers of flight — we feel little more than irritation. Flies can fly like nothing else on Earth. Flies are the miracle that we flap out of our faces.

I was walking along a hedgerow path with the sun in my face and became aware that the path ahead was glistening with flakes of gold: little scraps of life backlit, wings gilded by the sun. Naturally, I tried to get a better look at one of them and eventually managed it. I didn’t quite know how to react when I saw that it was a fly.

Only a fly. Only a miracle. What species? Oh, just one from the great groups of insects with a single pair of wings, the diptera, sometimes rather confusingly called “true” flies. The point is that we mustn’t confuse true with dragon or may or stone or fire or snake or saw or butter. They are profoundly different, if we take a moment to look.

And here was another: a fly that was unquestionably true. It was basking in the autumn sun, and if it wasn’t a fly and therefore a creature of ill-repute, we would admire it for its looks alone, never mind its extraordinary flying skills. It seemed to be wearing bright red goggles and a cream and black striped pyjama jacket, with the trousers dark and picked out tastefully with more cream.

It was a striking and elaborate-looking creature: I wonder how many times I have seen one. This was probably the first time I had really looked at one, being put in the mood to do so by the flying flakes of gold. I discovered that it was a flesh fly. Not an attractive name, I grant you; not a very attractive way of life, either. They are keen on rotting flesh: they like to land on it, mumble it and then drink it up as flesh soup. If flight excites our imagination in a good way, this sort of thing has rather the opposite effect.

Then you discover that flesh flies like to breed in carrion or dung or in the open wounds of mammals, and you find your sense of admiration rather compromised. But really, one should rise — fly — above such squeamishness and admire one of the most handsome flying machines that the world has managed to come up with.

Now, when you describe something as a fly you don’t narrow the field a whole lot. There are about 120,000 species in the world so far described: as soon as you get involved, even peripherally, with the smallest scraps of life, you have to deal with the largest sorts of numbers. There are many different species of flesh flies, and if you want to be precise about identification you have to dissect their genitalia — not something that you normally have time for on a dog-walk.

If a fly is going to be a true fly, it has to have two wings. Instead of having a second pair of wings — like flies of the butter and dragon persuasion — it has a pair of funky little organs called halteres that provide balance and a stunningly accurate appreciation of three-dimensional space. This is the secret of the fly — why a fly can fly like a fly.

All the same, flies are perhaps the only group of animals that I can kill without compunction. When there are fat horseflies on one of my horses, I slap without restraint, for affection towards horses rather than hatred of flies, but it’s all one to the flattened corpse. I have swatted tsetse flies in Africa with something approaching glee: the nip that a tsetse gives you is horribly sharp. And as for mosquitoes, also true flies, I expect that we all have blood on our hands, most of it our own.

I came upon an oak tree. On its trunk there were half a dozen more insects, squatting with the horrible indifference to gravity that flies possess. Is this another reason for human distaste, their habit of lolling at their ease on walls and ceilings, as if they weren’t creatures from the same world? I knew these flies. That’s mainly because they’re pretty distinctive: a shining black body and the bases of the wings a handsome deep chestnut: noonday flies. They are splendid things, if you don’t mind that they tend to be born — hatch out, anyway — in a cowpat.

But here is one of the thrilling truths about what happens when you start accustoming your eye, and with it your mind, to wild things and wild places: you look more, and so you see more. As a result, the miraculous nature of the ordinary is displayed before us as a rich gift day after day.

If you can bring yourself to look at the small and the disgusting, you will find things of beauty and wonder. The discovery of a new bit of life in an English hedgerow is as thrilling in its way as a journey to India to see tigers: and I’ve done both this year, so I should know. A journey into the small: an arrival at the miraculous.