Pictures this week of goats grazing on a precipitous dam wall in Italy are jaw-dropping. But why and how do they do it?

These newly released pictures of Alpine ibex goats scaling the 160ft face of the Cingino Dam in northern Italy are fascinating, but not unusual. It's a classic illustration of how well this species has adapted to its environment.

Ibex spend their life climbing up mountains to graze; then, at a certain time of day, they climb down again. They get different foods this way. They go uphill because the grass is better there in the summer, while in the winter it is better below. Here, I think, they are licking the stone for its minerals and salts. At a lower level there's plenty of grass, but they do need salts and minerals, and this must be a favourite place for them.

The ibex have soft, split hooves that can grip like a pincer. Big and supple with shortish, powerful legs, they are very sure-footed and have good eyesight. In the north of Italy or the Alps, there are predators – their calves, for instance, are eaten by eagles – so they have to be on the lookout all the time.