This December, Discovery Channel (DStv Channel 250) presents 'Discovering Ardi' — a landmark two-hour special documenting the discovery of the 4.4-million-year-old Ethiopian hominid fossil Ardipithecus ramidus, nicknamed Ardi.

The oldest skeleton from the hominid branch of our primate family tree to be discovered to date, Ardi not only represents a missing piece in the human evolution puzzle, but also answers age-old questions about how hominids became bipedal (two-footed).

Ardi was discovered in an Ethiopian desert 15 years ago and since then scientists have worked to extract, examine, analyse and piece together the partial female skeleton, as well as compare it to other African hominid fossils, including those from South Africa's famous Cradle of Humankind.

This intensive investigation revealed that Ardipithecus was a woodland creature with a small brain, long arms and short legs. The pelvis and feet show a primitive form of two-legged walking on the ground, but Ardipithecus was also a capable tree climber, with long fingers and big toes that allowed its feet to grasp like those of an ape.

In highlighting the significance of Ardi to South African journalists this week ahead of the premiere of Discovery Channel's 'Discovering Ardi', Professor Francis Thackeray, director of the Institute for Human Evolution at Wits University, said the discovery marked an important milestone in modern humans' understanding of their origins.

"We are living in very exciting times with regards to human evolution discoveries. This year has been electric because of Ardi. It confirms Charles Darwin's conclusions that humans and chimpanzees had a common ancestor, and that humanity must have evolved in Africa — a theory that the South African specimens Taung Child and Mrs Ples have long spoken to," Thackeray said in addressing the media on the 150th anniversary of the publication of Darwin?s ground-breaking book, 'Origin of Species'.

Thackeray added that South Africa had a lot in common with Ethiopia in terms of hominid remains, and that millions of years ago the environment in the Cradle of Humankind would have resembled a similar woodland environ to that that Ardi inhabited.

"We've discovered sites at Bolt's Farm in the Cradle that are between 4- and 4.5-million-years-old — about the same age as Ardi. So the search is now on to find something comparable to Ardi or even a new piece to this puzzle," Thackeray said.

In fact, 'Discovering Ardi' actually comes as South African palaeontologists prepare to reveal yet another possible historic scientific discovery at the Cradle, heightening the relevance and importance of this fascinating documentary for local audiences.

'Discovering Ardi' profiles a team of international scientists' investigation into Ardi, the other hominids she lived with, and the rocks, soils, plants and animals that made up her world, which were analysed in laboratories around the globe. The premiere follows the October 2009 publication of the team?s highly acclaimed findings in the prestigious journal Science.

'Discovering Ardi' is the result of a 10-year collaboration between the Middle Awash research project and Primary Pictures of Atlanta. Director Rod Paul and his team worked closely with the scientists to develop an unprecedented level of detail, accuracy and coverage of the discovery of Ardipithecus ramidus, much of it as it happened, on location in Ethiopia.

Viewers can further immerse themselves in the Ardi story at www.discovery.com/ardi, a special companion website to the 'Discovering Ardi' documentary.