A 325,000-year-old elephant tusk has been discovered in Saudi Arabia by archaeologists from Oxford University.

The group, led by Prof Mike Petraglia found the tusk preserved in an ancient lake in the Nefud Desert. It is believed to have belonged to an extinct species of elephant known as the Palaeoloxodon.

Prof Petraglia said: “The discovery of the elephant tusk is significant in demonstrating just how much the climate could have changed in the Arabian Desert.”