Note: One standout aspect of paleoanthropology is the lack of attention to female humans. Reconstructions often are scaled-down from male bones or are simply fabricated from fragments of skulls of undetermined sex. Some archaic species show little male / female dimorphism and it is not possible to conclusively identify the person’s sex from a few bones. The Gona discovery is therefore hugely important.
Turkana Boy: His skeletal parameters were used for “reconstruction” of female H. erectus pelvic anatomy. Why not? God made woman from Adam’s rib!
Predictably, the result was misleading and inaccurate!
PRESS RELEASE on “The First Female Homo erectus Pelvis, from Gona, Afar, Ethiopia”
Published in the Journal Science 14 November, 2008
Prepared by the Gona Palaeoanthropological Research Project
CRAFT Research Center, Indiana University, Bloomington, IN 47405
Scientists conducting fieldwork at the prehistoric site of Gona in Ethiopia have discovered the first documented complete pelvis of a Homo erectus female dated to around 1.2 million years ago (Ma). The soil formation that yielded the fossils is dated between 0.9 and 1.4 Ma, and we estimate the pelvis to be ~1.3 Ma. The new hominid pelvis was discovered by Ali Ma’anda Datto, an Afar colleague, on February 12, 2001. The pelvis was found in the deposits exposed north of the Busidima River, a seasonal river that feeds into the Awash River. Research continued in the area, and the excavation carried out in 2003 yielded the right and left os coxae (hip bones), and the last lumbar vertebra from one ancient woman. Numerous animal fossils, including a variety of wild antelopes, pigs, rats, horses, and reptiles were also found at the pelvis site. Gona is known for the discovery of the oldest stone tools in the world dated to 2.6 Ma. The Busidima hominid pelvis site is located ~12 Kilometers from the site of the oldest stone tool discovery.
The oldest female pelvis belonging to a hominid comes from the famous 3.2 Ma fossil skeleton widely known as ‘Lucy,’ (Australopithecus afarensis) also from Ethiopia. Lucy was discovered at Hadar in the Afar, a site that is contiguous to Gona, and located just a few Kilometers to the east. Additional fossil pelves known from the Plio-Pleistocene of Africa include the 2.8-2.5 Ma Australopithecus africanus (Sts14) from South Africa, and the Homo erectus juvenile male partial skeleton known as the “Turkana Boy,” (KNM-WT 15000, also sometimes known as the “Nariokotome Boy”) from Kenya dated to 1.53 Ma. Besides the Turkana Boy, few other pelves are known from this important period of human evolution. Because of the lack of a female pelvis in the paleontological record before this discovery, scientists relied heavily on information derived from the Turkana Boy, an important fossil that has been central for assessing the general morphology of female Homo erectus and for estimating female Homo erectus birth canal dimensions.
Can you imagine what a contemporary H. sapiens female reconstruction would look like if it was based solely on contemporary male H. sapiens skeletal evidence? Any history of human evolution without integration of female anatomy and behavior into “the story” is ridiculous, but “male-centric” science dominates.
Based on the Turkana Boy, the female pelvis has been inferred to be small and it was speculated that the birth canal could accommodate a neonate with a brain size of ~230 ml. As a result, before the new Gona discovery, Homo erectus females were believed to have delivered developmentally immature offspring with rapid brain growth after birth, also requiring a significant amount of maternal care similar to that of modern humans.
The new Homo erectus pelvis from Gona
The Busidima discovery includes a complete pelvis and last lumbar vertebra. It stands as the only complete and first female Homo erectus specimen known from the entire Early Pleistocene (dated between 1.80 to .78 Ma) of Africa. With this new discovery now we can confidently and accurately reconstruct female Homo erectus pelvis anatomy and draw important functional and behavioral conclusions. The Busidima pelvis is from a short-statured adult Homo erectus female.
However, the individual’s pelvis is obstetrically capacious and falls within modern female ranges. The size of the birth canal dimensions of a modern human female approximates the size of the head of their newborns making birth in humans difficult and often a traumatic process. Based on study of the relationships of modern human female birth canal and neonate head size, we estimate that the Busidima Homo erectus female was capable of delivering a baby with a maximal cranial capacity of 315 ml, which is 30% greater than previously estimated based on the incomplete juvenile male pelvis from Kenya (KNM-WT 15000). Modern humans at birth have a mean cranial circumference of ~347 mm (ranging between 320-370 mm, based on a large sample studied for this announcement publication) and we estimate that the Busidima pelvis is capable of birthing a neonate with a fetal head circumference of 318 mm, which is at the low end of modern human neonatal head circumference at birth. Modern human female pelvic inlet circumference averages ~385 mm compared to the ~353 mm that we estimate for the Busidima Homo erectus pelvis.
Comparison of three female pelves over the course of the last three million years. The pelvis of “Lucy” (Australopithecus afarensis, around 3.2 million years old) on the left, the new Gona pelvis (Homo erectus, about 1.2-1.3 million years old) in the middle, and a modern human female (Homo sapiens) on the right. ›Hi-res image
Our analysis indicates that the female Homo erectus pelvis was substantially larger than Australopithecus. The Busidima individual was of a small stature. Novel selective factors probably played a role resulting in a distinctive obstetric pelvis in Homo erectus allowing the delivery of large-brained offspring, and probably implying that aspects of the female pelvic shape in Homo erectus had evolved in response to increasing fetal brain size.
We conclude that Homo erectus may have experienced prenatal brain growth rate close to that of modern humans but with a slightly slower postnatal growth. Our study also suggests that the short-statured, broad-hipped Gona female Homo erectus pelvis is characteristic of temperate-adapted modern humans and not the tall narrow body form in Homo erectus formerly purported to have been an adaptation to tropical, semi-arid environments, and argued to signify ‘endurance running’ in this species. The paleoenvirornmental reconstruction of upper Busidima suggests open grasslands with tree cover and water sources along the main tributaries of the ancient Awash River.
Two questions: How can anthropologists claim to be accurately slicing and dicing hominids into species and describing the evolution of ape-hominids, WITHOUT FEMALES, whose “job” of growing new humans is obviously critical to understanding human evolution?
And why has H. erectus been rejected by “main stream” scientists as a direct ancestor of Homo sapiens, when the very evidence that is put forth to define Homo sapiens (Wonder Man) first arose in H. erectus, and not in H. sapiens? Increase in brain size; hunting strategies, weapons-tools, use of fire, “wanderlust” – adaptation to temperate climates and the resulting broad variety of body type that still marks H. sapiens today?
Personally, I would scrap the present “chopping up” of humans into so many species, and begin with the (radical) assumption that we (plus Neanderthals and Denisovans) are all Homo erectus, and that modern humans are a domesticated / juvenalized subspecies of H. erectus. This would certainly explain how “different species” were able to mate and produce viable offspring, among many other conundrums in human evolution. But, I’m a geologist and Asperger, and my thing is coherent systems of explanation, not a 19th C. passion for labeling objects and sticking them in drawers. I don’t believe this method of keeping resources “tidy” and available was ever meant to become the model for evolution. The emergence of genetics has revealed that evolution is far more complex and fluid than previously believed.