Carnivorous plant mystery solved
In 1995 Sir David Attenborough shared the latest scientific theory about how a tropical pitcher plant, Nepenthes rajah, gained nitrogen by digesting rodents.
A tree shrew was found inside one of the plant's fluid-filled, pitcher-like cavities and researchers believed it had been tempted there by nectar.
But last year, researchers from Monash University, Victoria, Australia, revealed that the tree shrews were not the prey of the plants.
Instead, the mammals were filmed using the pitcher plants as toilets, leaving their nitrogen-rich droppings in the bowl.
In this video clip, Sir David describes how the mystery was unravelled.
Attenborough: 60 Years in the Wild begins at 2100 on BBC Two, Friday 16 November.