Hundreds of thousands of people - possibly even a million or more - across southern Africa died from starvation and war during the 'crushing', the Difaqane or Mfecane, of 1816-17. One of the main causes of this often-forgotten catastrophe is finally being revealed by a network of ancient trees.
In the heart of a Cape cheesewood tree that had fallen among the stone walling of a forgotten civilisation is the story of one of the worst catastrophes ever to hit South Africa.
This disaster collapsed societies, killed perhaps two million people and changed what was to become South Africa forever.
The Zulu referred to this time as the Mfecane, the "crushing" - the Xhosa called it the Difaqane. It was a period in the early 19th century marked by widespread chaos, warfare, starvation and it even drove some to cannibalism. What fuelled this troubled time has been a source of debate. Some historians pointed to the slaving happening in Delagoa Bay, others argued it was caused by the rise of the Zulu state under Shaka.
But a picture is emerging of what was driving this chaos, and it is being provided by a number of ancient trees scattered across southern...