Though its physical features are the most human -
like of any australopithecine yet discovered, A. sediba is hundreds of thousands of years younger than the oldest fossils assigned to the genus Homo, meaning it is unlikely to be our direct ancestor.
Brain or no brain, A. sediba is significant because its anatomy is the most similar
of any australopithecine yet found to the true humans that evolved into us.
Connecting the dots between one
of these australopithecine species and Homo has been difficult, however, because the oldest known Homo remains are so few and fragmentary.
(The skulls in the two nonhuman pelvises are human baby skulls scaled down to the likely
size of an australopithecine baby's head, of which no fossils exist.)
Anthropologists have long assumed that the short
stature of australopithecines like Lucy was related to treetop living: Having short legs makes it easier to climb trees and gives stability when balancing on branches.
«What we really need are more specimens and some trail of fossils that shows us how LB1 got to Flores» while retaining
characteristics of australopithecines for more than a million years, Schoenemann observes.
Martin Häusler and Peter Schmid compared casts of Lucy's reconstructed pelvis (center) with a modern woman's pelvis (bottom) and the
cast of another australopithecine specimen from South Africa (top).
He was rummaging through boxes of animal bones previously excavated in the Sterkfontein caves, about 40 kilometers northwest of Johannesburg, where a number of
fossils of australopithecines — advanced apes similar to the famous Lucy — have been discovered.
In 1924, mining blasts at the Buxton Limeworks near Taung, South Africa, exposed a cavern containing the fossil bones of many small animals — and the two - and - a-half-million-year-old
skull of an australopithecine child.
The shape of the pelvis and the proportions of the limbs looked primitive —
reminiscent of australopithecines, or the earliest of human species, Homo habilis, from around 2 - 3m years ago.
But despite some modern traits, it has a
number of australopithecine features, and a brain size of only about 750 cc (compared to the modern human average of at least 1350 cc).
However, even from the bones that have been revealed so far, Little Foot looks like being at least as complete and important as Lucy, and will add tremendously to our
knowledge of australopithecines.
Consequently, we may emphasise the conclusions by Grabowski et al. (2015) and Jungers et al. (2016), who reported that the body
sizes of the australopithecines and of the early Homo representatives were similar, but also that certain australopithecine individuals (at least of Au.
For this reason, a few anthropologists, such as David Begun at the University of Toronto in Canada, have suggested that our ape ancestors spent a formative period in Europe — although they still agree that later hominin evolution, including
that of the australopithecines and the origin of our own species, occurred solely in Africa.
The list of prime suspects features several species
of australopithecine, but Harmand and Lewis also have their eye on Kenyanthropus platyops, a fossil discovered in 1998 very close to the Lomekwi 3 site.
Intriguingly, H. naledi's pelvis was more like
that of australopithecines such as Lucy, flaring outward more than that of modern humans.