The discovery of a skull (KNM-ER 1470) in East Turkana, Kenya, originally attributed to Homo habilis and later reclassified as Homo rudolfensis, was a landmark in paleoanthropology. This find, along with others, definitively proved the 'single species' hypothesis wrong, demonstrating that multiple early human ancestors, such as Paranthropus boisei, coexisted in the same place at the same time. It transformed the human family tree from a ladder of progress into a branching bush.

The 'bush' model of human evolution, powerfully illustrated by the KNM-ER 1470 find, has had a profound impact on how poets and thinkers imagine our origins. It has moved us away from a simple, heroic narrative of linear ascent towards a more complex and humbling view of a diverse and often dead-end evolutionary history. This idea of a branching bush, with its many offshoots and extinctions, has inspired a richer and more nuanced poetic engagement with the concept of human identity and the contingency of our existence.