Researchers have confirmed the age of possibly our oldest direct human ancestor at 1.98 million years old. The discovery was made after researchers conducted further dating of the early human fossils, Australopithecus sediba（南方古猿人） , found in South Africa last year.

A series of studies carried out on newly exposed cave sediments at the Malapa Cave site in South Africa, where the fossils were found, has assisted researchers to determine their more precise age at 1.98 million years old, making the Malapa site one of the best dated early human sites in the world.

A series of papers published in a special issue of the journal Science provide a new, more precise age for the fossils, as well as more detailed studies of the hands, feet, pelvis（骨盆） and brain.

Uranium lead dating of the flowstone, conducted by the University of Melbourne combined with palaeomagnetic（古地磁的） analysis sediments surrounding the fossils, conducted by La Trobe University provide the tightly constrained new age.

The team was able to pin down the age of the fossils to within 3000 years of 1.98 million years, a massive advance on the age range of around 200,000 years from the 2010 estimate.

Dr Robyn Pickering of the University of Melbourne's School of Earth Sciences, a lead researcher involved in the dating of the flowstone surrounding the fossils said researchers had long been searching for fossils from this time period to answer questions about the beginnings of our own genus（类，种） Homo.

"Knowing the age of the fossils is critical to placing them in our family tree, and this new age means that Australopithecus sediba is the current best candidate for our most distant human ancestor."

"The results of these studies present arguably the most precise dates ever achieved for any early human fossils," she said.