The puff adder is one of the deadliest snakes in Africa, and also an expert at camouflage. Can you spot the puff adder in the accompanying image, or in the footage before the narrator zooms in?

Puff adders, one of Africa's most widespread snakes, could be agricultural heroes in disguise. New research from the University of the Witwatersrand in Johannesburg, South Africa, has revealed that ...