“Little Foot” Hominid much younger, says new research
New research from James Cook University and the University of Johannesburg in South Africa has challenged assumptions about where humankind originated.
The age of “Little Foot”, an extremely rare, almost complete skeleton of the human ancestor Australopithecus africanus, has been hotly debated ever since its discovery at the Sterkfontein Caves, in the Cradle of Humankind world heritage area, South Africa.
Estimates have ranged from 2 to 4.2 million years, and the fossil is often thought of as an example of the oldest Hominid in southern Africa. The latest research has provided a new estimate of the age of Little Foot.
Little Foot was named for the four ankle bones which were found in 1980. The remainder of the skeleton was uncovered from 1997 onwards. In the years since, researchers from many countries have tried to determine Little Foot’s age and its place in the species classification of hominids, the early ancestors of humans who lived millions of years ago.
The new research by Prof Jan Kramers from the University of Johannesburg and Prof Paul Dirks from James Cook University adds the latest chapter in this debate.
In 2015, Prof D. Granger of Purdue University, USA and co-authors published an age of 3.7 million years for Little Foot in the authoritative science journal Nature. They used a pioneering technique to estimate the age of quartz crystals falling in from the surface into the cave sediments where Little Foot was found. Prof Granger’s result was soon accepted as the definitive age of Little Foot.
However this result, if correct, would make Little Foot older than Australopithecus afarensis hominids from east Africa, which include the 3.2 million year old fossils of “Lucy”.
Lucy is generally considered to be our ancestor. If 3.7 million years is correct, Little Foot would be an alternative candidate species from which we could have evolved, with implications for the exact location of our birth place in Africa. In addition, the fossils of Little Foot would then be at least a million years older than other dated hominin fossils in the Cradle of Humankind, contradicting earlier age estimates.
Using the same data as Granger, in this latest research Kramers and Dirks have now shown with new calculations and interpretations that Little Foot cannot be older than 2.8 million years.
In their analysis, they looked at the age of quartz crystals that accumulated directly around the fossils, but falling in from a now-eroded cave higher up, not from the surface. If correct, this means that the generally accepted sequence of hominids remain unchanged, and that Lucy is still considered the oldest human ancestor found.
The published research in the South African Journal of Science, which published a large number of papers about Little Foot over the years, is available here:
Prof Paul Dirks, James Cook University
P: (07) 747 81 5047
M: 0429 566 120
Prof Jan Kramers, University of Johannesburg
Johannesburg, South Africa,UTC + 2 hours at
P: +27 11 559 4755
M +27 76 045 1384