One does not often see snakes in the road and so it was interesting to see this puff adder (Bitus arietans) crossing a dirt road.
Notice how its body seems to dent in as it passes over small pebbles. Unlike several other snakes that seem to move at great speeds, the heavy-bodied puff adder moved slowly enough for me to observe its passage from one side of the road to the other. You can see its tongue more easily in this photograph:
It is commonly accepted that snakes use their tongue as a primary sensing device. They can ‘smell’ by flicking their tongue up and down to pick up various particles in the air. The chemical information collected is used in conjunction with the Jacobson’s organ, situated in the roof of the mouth. Puff adders mostly rely on their camouflage and the ability to lie still in order to catch their prey. When a Puff adder detects movement in its immediate vicinity, it will use its tongue to determine the source of the movement. This Puff adder headed up the raised bank at the side of the road.