The passerines form a family of birds with two toes pointing forward and one in reverse, engineered to grasp onto twigs, branches, wires and cables. This useful poise is better known as perching, a feat (forgive the pun) impossible to all except perhaps the deformed and the tightrope walkers.

The passerines are also characterised by their insistence on singing. They are better known as the songbirds. They tweet, they warble, they twitter and chirp, they cheep and chirr and chirrup and peep and trill. Among their ranks are the nightingales, the skylarks, the wagtails and the swallows.

So the passerines perch and sing. Some can be said even to belt out their little lungs, every bit the pocket soprano. Nature’s little clarinets do it both alone and in a choir, in the morning at the coming of the light and in the evening at the putting of the sun. Their voices can be so weightless they are carried on the wind, while others drown out the silence of molecules with a cacophony so intense that the passersby walking their dogs and the housewives by the open kitchen window can only stand in wonder at why the tree canopies are trilling as if their lives depended on it.

Do the songbirds know they sun will come round again, that their plaintive cries have been heard 93,000,000 miles away? Therein may explain the distance these passerines can travel to seek that sun half a world away. Some weigh no more than a pocket watch yet travel through time more than either the big or the little hands. The swallow claps its perfect wings a million times and some, over the length of Africa and some. He wheels and dips all summer long over hill and dale and seas of corn, market towns and football fields earmarked for development. And when he has seen enough and eaten enough he summons the brood and does it all again, back to South Africa and the sun inching south.

The passerine knows no boundaries. On signs reading – NO TRESPASSING, PRIVATE PROPERTY – he perches and warbles, singing his cares away.