Long before our own species--Homo sapiens--evolved, there were other human species which may have been ancestral to us. Homo erectus emerged about 1.9 million years ago, with the earliest fossil evidence in East Turkana in Africa. There are some paleontologists who prefer to use the designation Homo ergaster for some of the African finds. With regard to the debate over the use of Homo erectus versus Homo ergaster, biological anthropologist Barbara King, in her book Evolving God: A Provocative View of the Origins of Religion, points out:
“A debate of this sort is critical for taxonomists and paleoanthropologists, but not for us: a single term suits our purposes just fine.”
I will follow Dr. King’s suggestion in the section that follows.
By 1.6 million years ago, Homo erectus had spread into Asia and there are fossil finds of this species in China, India, and Indonesia. By 1.2 million years ago, Homo erectus was living in Georgia (the country) where the species is sometimes called Homo georgicus by paleontologists who view these fossils as an intermediate between the earlier Homo habilis, which is found only in Africa, and Homo erectus. Most paleontologists currently classify it as Homo erectus. The skull size ranges from 600 to 680 cubic centimeters making it the smallest hominid skull found outside of Africa. Interestingly enough, these skulls appear to have a modern spinal cord which means that there would be no constraints on language.
With regard to Homo erectus in China, Chris Stringer and Peter Andrews, in their book The Complete World of Human Evolution, report:
“The skull was relatively elongated, but low, with a flat forehead. It was very broad across its base and poorly expanded higher up.”
While the cranial capacity was large—1,000 cubic centimeters—compared with early ancestors, the walls of the skull were fairly thick.
Stringer and Andrews also report:
“The bones of the rest of the skeleton were heavily built, with thick walls, suggesting that erectus had a lifestyle which placed heavy demands on the skeleton.”
The growth pattern in
erectus infants appears to be more ape-like than human. In modern humans the first year of life is characterized by major brain growth. Fossil evidence from a skull found at Mokokerto, Java, suggests that the brain growth rate in infants was more like other mammals in that most of it took place prior to birth.
Homo erectus also traveled into Spain where archaeologists working at Sima del Elefante have found remains dating back to 1.2 million years. The initial findings on the remains at this site show that the Homo erectus was not in good health but suffered from tooth infections and abscesses. At Gran Dolina in Spain, early human ancestors were butchering deer, rhino, and bison about 800,000 years ago. Barbara King reports:
“Most experts agree that this was not erectus but a different type of hominid (Homo antecessor), which suggests that variations within the Homo lineage was pronounced.”
In most areas, evidence of
Homo erectus disappears about 300,000 years ago, but in Indonesia,
Homo erectus appears to have survived until quite recently. Thomas Suddendorf, in his book
The Gap: The Science of What Separates Us from Other Animals, writes:
“New dating of three Indonesian skulls has yielded estimates of between 40,000 and 70,000 years ago. Another study suggests that the descendents of ‘Java Man’ may have survived until as recently as 27,000 years ago.”
This means that
Homo sapiens and
Homo erectus lived at the same time and may have interacted.
With regard to the brain, the size of the Homo erectus brain ranged from 750 to 1200 cubic centimeters (with the notable exception of the finds in Georgia). In other words, the brain was smaller than Homo sapiens, which has an average 1350 cubic centimeters. The frontal lobes are developed in a manner similar to early homo sapiens. There is asymmetry between the right and left brain as there is in modern humans.
At the site of Zhoukoudian in China, there is evidence for Homo erectus occupation from about 670,000 years ago to about 400,000 years ago. There is some evidence for the use of fire at this site, but this is disputed.
With regard to tool use, Homo erectus and Homo ergaster sites are often associated with stone tools known as Achuelian handaxes. In making these tools, the makers had a mental template of what the final product would look like. With regard to the function of the handaxe, Chip Walter, in his book Thumbs, Toes, and Tears and Other Traits that Make Us Human, writes:
“The hand axe was a Stone Age version of the Swiss Army Knife, and considerably more sturdy and refined than the small cutting tools H. habilis used.”
Chris Stringer and Peter Andrews report:
“It was clearly a multipurpose tool, since it combined a point at one end, a blunt butt at the other, and scraping and cutting surfaces along the sides, and it also provided an additional block of raw material for the production of fresh and sharp flakes when these were needed.”
The Achulian handaxe seems to have been more than simply a utilitarian tool. Each of the handaxes, regardless of the stone from which it was shaped, took an almond or teardrop shape. Carl Zimmer, in his book
Smithsonian Intimate Guide to Human Origins, writes:
“Instead of simply chipping a rock to produce a sharp edge, hominids now sculpted rocks until they took on a predetermined shape.”
Chris Stringer and Peter Andrews report:
“The people who made the handaxes clearly had a specific shape in mind, and often went far beyond a purely utilitarian form in the care with which they produced them.”
This raises an interesting question: were Achulian handaxes also symbols? Did their shape have meaning for their makers beyond simple utility?
Both language and religion are symbol systems and the archaeological record for Homo erectus and Homo ergaster offer some tantalizing suggestions of symbolism. Found in some sites is red ocher. Walter Fairservis, in his book The Threshold of Civilization: An Experiment in Prehistory. writes:
“The red ocher sticks, known by their wear to have been used, [offer] evidence of color usage—perhaps, as the excavators suggest, for body painting. Red ocher, however can also be material for drawing and painting. Since art is communication functional in its universality as a means of describing and thus controlling the supernatural, the red ocher is an important clue.”
Fairservis also writes:
“It is this ability to use graphic or oral symbols consistently to convey ideas that distinguishes man. Are our humble red ocher sticks the evidence for the conveyance of ideas through symbols no matter how simple?”
Is there evidence of language among
Homo erectus? Ian Tattersall, in his chapter in
The Epic of Evolution: Science and Religion in Dialogue, writes:
“There are incipient signs of the flexion of the cranial base that signals the presence of a vocal tract capable of producing the sounds associated with articulate speech, but speech and hence language are belied by the narrowness of the thoracic vertebral canal that carry innervations of the thoracic musculature.”
The nerves that pass through the thoracic vertebral canal control breathing and thus it looks like H. erectus lacked the fine breathing control which is necessary for modern speech. Chip Walter writes:
“…despite his prodigious intellect, H. erectus was almost certainly incapable to speech as we know it. Standing upright had helped rearrange the shape of his throat and larynx, but generally scientists agree that the relationships among tongue, lungs, throat, and nose still needed fine-tuning before speech was possible.”
In other words, they lacked our fine control of the musculature that is needed to generate speech. On the other hand, Chip Walter suggests: “Perhaps he had other ways of communicating that didn’t require words.”
Concerning language Steven Pinker, in his book The Language Instinct: How the Mind Creates Language, writes:
“Homo erectus, which spread from Africa across much of the old world from 1.5 million to 500,000 years ago (all the way to China and Indonesia), controlled fire and almost everywhere used the same symmetrical, well-crafted stone hand-axes. It is easy to imagine some form of language contributing to such successes, though again we cannot be sure.”
Do any of the
Homo erectus sites show evidence of religion? The evidence here appears to be skimpy at best. In one instance there is a skull—the Bodo skull from Ethiopia—which may have been defleshed. The ethnographic record shows that burial customs in many cultures involve the defleshing of the corpse and so some people interpret this as evidence for a belief in an afterlife.
In Morocco, near the town of Tan-Tan, archaeologists found a small quartzite figure which dates to about 400,000 years ago. There is not only evidence of human modification on the piece, but also traces of a red pigment (hematite). This may be an example of early art and, as such, an example of symbolism.