Why is Dinka so tall?

Though there has been a lot of speculation about the cause of the tall height of the Dinka people, the most common explanation is their nutrition which is said to primary milk and organic food.

Who are the tallest tribe in the world?

The tallest major tribe in the world is the Tutsi (also known as the Watussi) of Rwanda and Burundi, Central Africa whose young adult males average 1.83 m (6 ft).