There’s a certain shift in manner, not unlike a change of gear, that occurs with the move from pleasantries to business. You can see it in the walk of a tennis-player getting ready for the first serve of the match, or in the voice of a smart operator closing in on a deal.

I’ve seen it in lions as they move from socialising to hunting. I’ve seen it is leopards as they lock on to a target and shift from prowling to stalking. And last time I was in the Luangwa Valley in Zambia I saw it in a pack of wild dogs.

Dogs are merry things to observe, especially when there are pups around, as there usually are. We caught up with them them as the light was beginning to go; they were all busy greeting each other, so it seemed that every dog was on the best possible terms with every other dog.

Then the adults set off on a merry old canter, as if they were out for a jolly, and why not? Such a nice evening. And then, in a single instant of time they shifted gear. They didn’t so much as change pace as shift the level of intensity: one moment it was fun, the next it was serious. Now it was business.

Their backs lowered, their stride lengthened and the mood morphed from canter and banter to gallop and death, for this was the most serious business of them all. They were no longer looking at each other: they were focused on the puku before them. Puku are medium-sized antelopes, foxy-red, the males with neat horns.

The puku saw them coming and scattered, but the dogs were already among them. Two of them split a puku from the herd and it looked like a goner, but another dog brought down a puku all by itself and that was supper sorted, that was the day sorted, that was survival sorted for another 24 hours. All at once the rest of the pack were alongside and a fine male puku was now a meal.

One dog spilt off from the eagerly feeding crowd and went to the spot where the pups had been sitting as if watching a favourite film. He regurgitated a little meat: that’s what it’s all about, young’uns. After this fragrant appetiser they followed the adult back to the rest and ate their share.

A little later, the pups were playing a mad game with a bit of dead puku. It was all the best of fun: but there will come a time soon when such matters are – well serious. Deadly serious.

• I was co-leading a trip with Wildlife Worldwide https://www.wildlifeworldwide.com/discover/zambia