Last updated at 10:07 26 April 2007

Viewed from such a height, these majestic elephants look like nothing more than black mirages against the barren landscape.

They are trudging across the sands, dry river-beds and rocky outcrops of Damaraland in Namibia, where they will use their trunks to burrow deep into the arid ground in search of lifegiving water.

The African elephant is the only animal on the continent that digs for water, delving several feet into the earth until they hit an underground spring to quench their thirst.

Once they have hit liquid gold, they will suck it up through their trunks, then spray it into their mouths, drinking as much as two gallons at a time, and swallowing up to 50 gallons a day.

Afterwards, they will move on and other creatures will rush to drink at the open wells they have left behind.

Elephants are thought to teach each other about likely water sources, and a typical herd roams over an incredibly large distance in search of food, travelling up to 500 miles from home at a normal walking rate of 3.5mph to 5mph.

But, despite their bulk, they are still capable of far faster speeds if threatened - a charging elephant can rush at speeds hitting 25mph.