Africa's tallest dam takes shape in Ethiopia

The construction site on the Omo River in southern Ethiopia, where Africa's tallest dam is being built Photograph: Xan Rice Photograph: guardian.co.uk The Karo ethnic group lives near the Omo river. In these traditional societies of livestock farmers, the kalachnikov rifle brought in by Sudanese refugees is displayed as a trophy and constitutes the household's wealth Photograph: Sipa Press /Rex Features Photograph: Sipa Press /guardian.co.uk The canoe of the Karo tribe crossing the Omo river, Ethiopia Photograph: Remi Benali/Getty Images Photograph: Remi Benali/guardian.co.uk In the village of Korcho, a Karo warrior overlooks the Omo river. The Karo are one of the most endangered ethnic groups in Ethiopia. They number today less than 500 individuals Photograph: Remi Benali/Corbis Photograph: Remi Benali/guardian.co.uk A Karo tribesman carries a gun over his shoulder as he guards his goats on a bank of the River Omo that snakes into neighbouring Kenya Photograph: AP Photograph: guardian.co.uk A Karo boy, carrying his little sister, looks across the Omo River from the hills of Korcho Photograph: Gianni Giansanti/Corbis Photograph: Gianni Giansanti/guardian.co.uk