In 2013, an astounding new discovery shook up the field of early human evolution.
The bones of a new species of extinct hominin called Homo naledi were discovered in the Rising Star Cave in South Africa and unveiled to the world in September 2015.
The new species had a primitive braincase but fairly modern hands and feet, which is a strange mixture.
To find out more, BBC Earth spoke to Professor Chris Stringer at London's Natural History Museum, where the reconstructed hand and jaw of H. naledi was on display as part of a new exhibition on human evolution.
The new species has not yet been dated, and is not expected to be until at least the end of 2016. But researchers believe it could sit right at the base of the line Homo, that led to us.
If it does, it was one of the earliest humans ever to walk the Earth, as Stringer explains in the video above.
Video produced by Pierangelo Pirak and Melissa Hogenboom.
Human evolution is a permanent exhibition at the Natural History Museum in London, UK.