The ancient Nazca people of Peru are famous for the lines they drew in the desert depicting strange animal forms.

A further mystery is what happened to this once great civilisation, which suddenly vanished 1500 years ago.

Now a team of archaeologists have found the demise of the Nazca society was linked in part to the fate of a tree.

Analysing plant remains they reveal how the destruction of forests containing the huarango tree crossed a tipping point, causing ecological collapse.

The team have published their findings in the journal of Latin American Antiquity.