Trump: 'We Will Build a Great Wall Along the Southern Border'

The Republican Presidential candidate Donald Trump has set out his policy on immigration, reiterating his plan to build a wall along the US border with Mexico following a meeting with the Mexican president.

The first ever continent-wide survey of elephants population in Africa shows that it has been cut by a third in the last decade.

Scientists have found what they believe may be the oldest fossils on earth in Greenland. They take the form of wavy lines in rocks more than three-and-a-half billion years old.