In 2003, archaeologists excavating in a cave on the Indonesian island of Flores made a discovery that forced scientists to completely rethink conventional theories of human evolution.

They reported the discovery of a new species of human, one that lived as recently as 12,000 years ago, at the same time as modern humans.

But others disagreed, arguing the one-metre-high skeleton was a modern human that suffered from a deformity known as microcephaly.