After reading this chapter, students should be able to:
recount the history of discovery of Lower Paleolithic hominins and how it relates to our understanding of evolution.
describe the evolution of hominins from 1.7-1.6 million years ago to 250,000 years ago, the Lower Paleolithic/Early Stone Age.
explain how H. ergaster differed from earlier hominins.
understand the relationships between H. ergaster and later hominins.
describe the relevant biological and morphological differences that relate to each species, and why current phylogenies are constructed as they are.
be conversant with the important fossils and sites from which evidence is drawn.
extrapolate from biological and artifactual evidence, what we know about the social and cultural behavior of various hominins of this period.
explain hominin migrations, and the differing implications of early and later dates for hominin migration out of Africa.
describe the differences between Acheulean African, European, and Southwest Asian people and non-Acheulean/Acheulean age people found in East Asia and Indonesia.
describe Acheulean culture, including tools, behavior, and biology.
relate what is known about early, failed attempts at European colonization.
understand the implications of new finds at Dmanisi, dates from Java, and other current controversies.
be conversant with the debates over hunting vs. scavenging, site modification, fire use, symbolic and other current issues
Anatomy. Homo ergaster
, a strictly African species, existed between 1.8-1.7 million and 600,000 years ago. Important sites include Koobi Fora (East Turkana) and Nariokotome III (West Turkana).
The Turkana Boy.
KNM WT 15000, also called the Turkana Boy, is a West Turkana skull and skeleton dated 1.56 million years old, which illustrates the cranial and postcranial morphology of an immature male. Unlike tiny, apelike Lucy, he was 1.62 m (5 ft 4 in) at death, and would have reached 1.82 m (6 ft) at adulthood. His body was almost modern, but his adult brain was only 880 cc, with a long, low, thick braincase, receding forehead, bony browridge, prognathic chinless jaw, and large molars. His nose, however, was human-like.
Human Evolution and the Inferences from the Turkana Boy.
The Turkana Boy had no apelike reliance on trees. His narrow pelvis and barrel-like chest emphasize bipedalism. A narrow pelvis in females implies a constricted birth canal, limiting the amount of brain growth before birth, and prolonging infancy, as in modern humans.
A reduced digestive tract indicates a diet containing more meat and tubers. Cooking might have made food more digestible although persuasive evidence for fire use post-dates 250,000 years ago, after H. ergaster
had been replaced by other hominins.
The hot, dry environment of Africa may explain the slim, tall body, which promotes heat dissipation; the projecting, external nose conserved moisture. He may have had hairless skin for efficient sweating.
The brain was large enough to invent new tools, but too small to further innovate. Other H. ergaster
fossils confirm these traits, and that sexual dimorphism was similar to living people, suggesting social organization approximating the modern.
The Relationship of Homo ergaster to other Hominins H. ergaster
, discovered in the 1970s, was originally classified as H. erectus
due to shared morphological features with the East Asian hominin discovered in 1891, but despite some dissent, due to their relative ages, most now believe that that H. erectus
originated in Africa, later migrating east. In addition, African H. ergaster
skulls are more primitive than H. erectus
It was once believed that H. erectus
was directly ancestral to H. sapiens
. If so, H. ergaster
would be an early stage of H. erectus
. But fossils dating after 600,000 years ago now indicate that H. sapiens
evolved in Africa while H. erectus
continued on largely unchanged in East Asia. As H. sapiens
emerged in Africa, Homo neanderthalensis
, was evolving in Europe. H. sapiens
and H. neanderthalensis
last shared a common ancestor about 600,000-500,000 years ago; this ancestor has been designated H. heidelbergensis
. Thus H. ergaster
is ancestral to H. erectus
and H. heidelbergensis
and its descendants, H. sapiens
and H. neanderthalensis
may have evolved suddenly from H. habilis
or H. rudolfensis
in adaptive response to increased aridity and rainfall seasonality across Africa about 1.7 million years ago. Or, a "bush" of human species may have emerged 3 to 2 million years ago, with H. ergaster
being a totally separate branch. At Olduvai Gorge H. habilis
or its variants persisted until 1.6 million years ago, but thereafter H. ergaster
displayed cognitive and behavioral advances over H. habilis
, linked to its ability to create new tools, colonize arid, seasonal environments, and expand out of Africa.
The Acheulean Hand Axe Tradition
Oldowan toolmakers produced sharp flakes but did not shape their cores, using them as hammers to process marrow bones. H. ergaster
meticulously shaped cores into the characteristic hand axe: completely bifacially flaked, teardrop-shaped with a broad base and rounded point. Ovals, triangles, and sometimes cleavers were common. These define the Acheulean cultural tradition, spanning over a million years and three continents.
In Europe and Southwest Asia, Acheulean assemblages belong to the Lower Paleolithic, and in Africa to the Earlier Stone Age (ESA). The oldest, from West Turkana, are 1.65 million years old, and thereafter they appear throughout Africa. Some are associated with Australopithecus boisei, but this shows only that boisei persisted after H. ergaster
emerged, not that they made Acheulean tools. At other sites, the tools are associated with the larger-brained H. ergaster
, the more likely toolmaker. Acheulean tools also continued unchanged after 1 million years ago, when robust australopithecines had become extinct.
The oldest Acheulean assemblages contain Oldowan-style cores and flakes alongside hand axes, but nothing is truly intermediate: the hand axe tradition appeared abruptly, perhaps paralleling the punctuational genesis of H. ergaster
Hand Axe Function
While "hand axe" implies a hand-held chopper, many are too large, and their precise use remains a puzzle, a problem increased at sites with hundreds of closely packed hand axes with no obvious signs of use. Marek Kohn and Steven Mithen proposed that Acheulean males may have used them to impress females, then discard them.
Most sites have smaller numbers of hand axes that show signs of use. They came in many sizes and shapes, probably serving multiple utilitarian functions. Some may have been hurled, others used as portable sources of flakes, others to chop or scrape wood. Experiments show that they are effective butchering tools.
Variation within the Acheulean Tradition
The Acheulean industry persisted largely unchanged from 1.65 million years ago until 250,000 years ago. Different raw materials often account for variations. Yet there are changes: early Acheulean hand axes are thicker, less trimmed, and less symmetrical, with a few deep flake scars. Experiments relate this to manufacture using hard (stone) hammers. Late Acheulean hand axes are thinner, trimmed, straight-edged, highly symmetrical, with shallow, flat flake scars produced with soft (wooden or bone) hammers. Late toolkits often include refined flake tools foreshadowing Mousterian and Middle Stone Age traditions. Like these later people, late Acheuleans prepared cores to provide flakes of predetermined size and shape. Archaeologists call such deliberate core preparation the Levallois technique. Future research may show two distinct periods, divided by rapid artifactual change 600,000 years ago, possibly coinciding with the emergence of Homo heidelbergensis
To understand the controversies surrounding H. erectus
and H. ergaster
, the discovery and dating of its East Asian fossils must be examined.
The Discovery and Dating of Homo erectus in Java
In 1891, Eugène Dubois found a low-domed, angular, thick-walled human skullcap with a large shelflike browridge near Trinil, Java (Indonesia) - the first of several discoveries. He believed he had discovered an erect, transitional form between apes and humans, and called it Pithecanthropus erectus ("erect ape man"). Homo erectus
became its scientific name, reflecting its humanness.
Dubois was discouraged by the dismissal of his finds, and was vindicated only in 1936 when new fossils were found, and numerous other examples followed. The volcanic nature of Java has permitted their dating using potassium-argon dating, but the results are controversial because the stratigraphic positions of the key fossils are poorly known. Some believe that H. erectus
reached Java only after 1 million years ago, while others argue for 1.65 million years or before. The former is consistent with the view that H. ergaster
was the first human species to leave Africa, while the latter might mean that H. ergaster
and H. erectus
evolved from a shared ancestor that left Africa earlier, or even that H. erectus
originated in Asia and migrated to Africa.
The Discovery and Dating of Homo erectus in China
Equally important Homo erectus
fossils are found in China, where in 1921, at Zhoukoudian cave, J.G. Andersson excavated human remains. Eventually many more fossils were found, representing more than 40 individuals of both sexes and various ages. Originally called Sinanthropus pekinensis ("Peking Chinese man"), they were compared to Javan Pithecanthropus, and deemed variants of a single primitive human species. The Chinese fossils differ from the Indonesian, showing a separate evolutionary trajectory. They have been dated to between 800,000 and 400,000 years ago, mainly by paleomagnetism, biostratigraphy, and climatic shifts.
The Archaeology of Chinese Homo erectus
Unlike in Java, Chinese H. erectus
are often directly associated with stone artifacts, as at the Lantian and Zhoukoudian sites. At Nihewan Basin, very early dates have been suggested by paleomagnetism and sedimentation rates, dating crudely flaked stones to 1.3 million years ago. As yet, these artifacts and dates are not generally accepted.
In the 1940s, Hallam L. Movius noted that sites east of northern India, including China, lacked hand axes, despite other tools shaped with similar skills. Movius drew a line separating the Acheulean tradition of Africa, Europe, and western Asia from the non-Acheulean tradition in eastern and southeastern Asia. If people colonized East and Southeast Asia by 1.3 million years ago, hand axes might not yet have been invented. Or, they may have migrated through regions without suitable raw materials and lost the knowledge of the tradition.
THE DISPERSION OF Homo ergaster AND THE FATE OF HOMO ERECTUS
Archaeology shows that about 1.5 million years ago, shortly after appearing in Africa, H. ergaster
colonized the northern and southern margins of the continent, passing through a more hospitable Saharan region. A group on the periphery might periodically outgrow its resources, and a splinter party could find empty territory nearby. From northeastern Africa, such groups probably colonized eastward toward China and Indonesia and northwestward toward Europe without even knowing that they had left Africa.
The Initial Expansion of Homo ergaster from Africa
Assuming Homo ergaster
lacked boats, its first stop would be modern Israel, where we find 'Ubeidiya in the Jordan Rift Valley, the oldest Acheulean site outside of Africa. Artifacts resemble early Acheulean artifacts from Olduvai Gorge and date to between 1.4 and 1 million years ago.
The Expansion of Homo ergaster to Eurasia: the Dmanisi Discoveries
Dispersal into eastern Asia occurred by 1 million years ago, perhaps earlier. Until recently, the oldest accepted European evidence was about 800,000 years old, from Gran Dolina cave, Spain. However, recent discoveries at Dmanisi, Republic of Georgia, may be earlier. Dmanisi lies 1500 km (940 miles) north of 'Ubeidiya, and yielded more than 1000 artifacts and many human fossils.
Paleomagnetism dates Dmanisi to between 1.77 million and 780,000 years ago, and identification of the 2000 mammal bones support the earlier date. The Dmanisi assemblage contains no hand axes, only flaked pebbles, suggesting formation before Africans invented hand axes 1.7-1.6 million years ago. However, as many later sites in Africa and Europe lack hand axes, their absence need not indicate a pre-Acheulean site.
The form of one skull, D2700, presents the strongest argument for a date of 1.7-1.6 million years. It closely resembles KNM-ER-1813 from East Turkana (Koobi Fora), assigned to Homo habilis
due to its 600 cc braincase, lack of a projecting, external nose, and other facial features. The latest known H. habilis
at Olduvai Gorge dates to 1.6 million years ago. The other two Dmanisi skulls are similar to north Kenyan Homo ergaster
, and could also be 1.6 million years old. Either two human species expanded from Africa early, or the definition of H. ergaster
must expand to include fossils otherwise assigned to H. habilis
The Persistence of Homo erectus in Java
By 600,000-500,000 years ago, along with more sophisticated hand axes, hominins with larger, more modern braincases appeared in Africa, probably evolving abruptly from Homo ergaster
. They closely resembled Europeans of 500,000-400,000 years ago, so are grouped together as Homo heidelbergensis
. H. heidelbergensis
' expansion from Africa probably explains the introduction of Acheulean artifacts to Europe about 500,000 years ago. Homo heidelbergensis
may be the last shared ancestor of the Neanderthals and modern humans.
The latest H. erectus
fossils come from the sites of Ngandong and Sambungmacan, Java. The skulls are larger than classic Indonesian H. erectus
, but exhibit the same characteristics, and are deemed an evolved variant of H. erectus
. Biostratigraphy indicates an age of less than 300,000 years and ESR dates narrow this to between 53,000 and 27,000 years ago. If the dates are valid, they provide strong support for the survival of Southeast Asian H. erectus
until it was replaced by modern humans after 60,000 years ago.
HOMO HEIDELBERGENSIS AND THE EARLIEST OCCUPATION OF EUROPE
Dmanisi puts people at the "Gates of Europe" by 1 million years ago, and perhaps 1.7 million years ago. Yet no European site is indisputably older than 800,000 years, and only one or two are older than 500,000 years. This implies obstacles to early human settlement, particularly glacial conditions. Fossils from Petralona, Greece, and Arago, France, suggest descent from Homo heidelbergensis
: expanding Africans who brought the late Acheulean tradition to Europe c. 500,000 years ago.
had large, prognathic faces, massive, chinless jaws with big teeth, large browridges, low, flat foreheads, and thick skulls. Yet they had a much enlarged brain, averaging over 1200 cc. Their anatomy and geographic distribution make them a plausible common ancestor for Neanderthals and modern humans.
Unsuccessful European Colonizers: Homo antecessor and the Ceprano Skull Homo heidelbergensis
was not the first to attempt European colonization. At Gran Dolina cave at Atapuerca, Spain, Layer TD6, dated to between 857,000 and 780,000 years ago, yielded fossils from at least six individuals between three and 18 years of age. More modern than Homo heidelbergensis
, they are designated Homo antecessor
. Additionally, 200 artifacts were found, consisting of hammerstones and flakes but no hand axes, although they were common elsewhere at this time. As with Asian H. erectus
, the technology may have been lost. Over 1000 animal bones with cut, chop, and scrape marks were also found.
Unlike TD6, Ceprano has no artifacts, and only one human fossil, important for its age and form: a human skullcap in layers dated to 900,000-800,000 years old. Similar to Javanese Homo erectus
fossils, it implies another early, failed colonization attempt.
Brain Expansion and Change within the Hand Axe Tradition
The Acheulean tradition, as noted, had an early phase, before 600,000 years ago, with thick, asymmetric hand axes and a later phase, after 600,000 years ago, with thinner, trimmed, more symmetrical examples. This greater technological sophistication may have been crucial for colonization of Europe.
Early two-dimensional symmetry, though crude, probably signals a cognitive advance. The even greater three-dimensional symmetry of the late Acheulean may mark an equally important cognitive advance, allowing mental rotation of the final tool before it was actually produced. Between 1.8 million and 600,000 years ago, brains remained stable at 65 percent of modern size; afterwards, they increased to about 90 percent. The tool-making transition may correlate with brain changes heralding the emergence of Homo heidelbergensis
The Evolution of the Neanderthals in Europe
After 500,000 years ago, Neanderthals evolved in Europe while modern humans evolved in Africa. Older finds from Swanscombe, England, and Steinheim, Germany, augmented with recent finds at Sima de los Huesos, Atapuerca, Spain, shed light on Neanderthal development.
Fossils from Sima are 500,000 to 400,000 years old, placing them early in the interval between Homo heidelbergensis
and the emergence of fully fledged Neanderthals at 130,000 years ago. Neanderthal skull volume averages 1520 cc; modern humans 1400 cc. Two Sima skulls are 1125 and 1220 cc, but the third is 1390 cc, within Neanderthal range, the largest older than 150,000 years. The Sima skulls also combine distinctively non-Neanderthal and Neanderthal features.
EVIDENCE FOR EARLY HUMAN BEHAVIOR APART FROM STONE ARTIFACTS
Knowledge of Acheulean people comes from fewer than 50 archaeological sites scattered in time and space, not always well-dated. The behavioral implications are often ambiguous. Despite this, we can say a few things about early human behavior apart from stone tools.
Raw Materials besides Stone
Animal bones at many sites suggest their use as hammers, retouchers, anvils, or cutting boards; a few were percussion-flaked to produce bifaces, scrapers, and choppers. No sites contain bones cut, carved, or polished to form points, awls, or perforators until after 50,000-40,000 years ago - associated with modern humans.
Bamboo rivals or exceeds stone for sharpness and durability, and was likely used in eastern Asia, where hand axes are lacking. Actual bamboo artifacts remain unknown.
Unquestionable wooden artifacts have been found at only four anaerobically preserved sites dated between 780,000 and 300,000 years ago. They are mostly nondescript, except at Schöningen, Germany, where three complete, indisputable wooden thrusting spears were found.
Shelters must have been needed in Eurasia, but apparently were ephemeral, leaving ambiguous traces. Patterned arrangements of large rocks found at several sites may be foundations for huts or windbreaks, but natural processes cannot be ruled out. At other sites, oval or round clusters of artifacts, bones, and debris could mark hut interiors. Evidence for housing becomes abundant and unambiguous after the advent of fully modern humans between 50,000 and 40,000 years ago.
Fire Homo ergaster
(or H. erectus
) may have mastered fire for warmth and cooking before colonizing Eurasia, but direct evidence is tenuous. Patches of baked earth 1.5-1.4 million years ago at Koobi Fora and Chesowanja are probably natural. Other early Paleolithic sites containing ash, charcoal, burned bones, or patches of burned earth are probably the same. Swartkrans Cave, with burned animal bones, may provide the strongest evidence, as they are absent in older layers.
The oldest widely accepted evidence comes from Zhoukoudian Locality 1 in China dated to between 500,000 and 240,000 years ago. Numerous charred bones and dark lenses are interpreted as hearths, directly associated with numerous artifacts.
In Europe, several sites have evidence for fire dated between 400,000 and 300,000 years ago, and others date between 186,000 and 127,000 years ago.
European Neanderthals and their African contemporaries after 130,000 years ago produced many clear hearths. The caves used by these later peoples, which preserve sites better, may contribute to this contrast.
Three examples of possible art are most convincing. First, fragments of humanly introduced ochre have been found with Acheulean artifacts and animal bones at Kapthurin, Kenya, Duinefontein 2, South Africa, and Twin Rivers, Zambia. Arguably, they might have been for utilitarian use, but artistic behavior cannot be ruled out. Second, an elephant bone fragment from Bilzingsleben, Germany has incised fanlike lines (not butchery marks) created simultaneously with one stone tool. Third, a small, definitely humanly modified lava pebble from Berekhat Ram (Syrian/Israeli border) may represent a crude human figurine. Clear artistic objects become commonplace only after 50,000 years ago, with modern humans.
Diet and Food Procurement
Plant Foods: Foraging.
Remains of edible plants are found at some Acheulean-age sites, but may not be linked to human activity. One H. ergaster
(KNM-ER 1808) from Koobi Fora, Kenya, dated to roughly 1.7-1.6 million years ago appears to have a condition that could have been caused by an overdose vitamin A from carnivore livers or honeybee eggs, pupae, and larvae.
Animal Foods: Hunting and Scavenging.
Archaeologists once simply assumed that Achuelean people were big-game hunters, killing and butchering animals with their tools. In the 1970s, specialized zooarchaeological analyses revealed that animal bones could represent human kills or carnivore kills and natural deaths, subsequently scavenged by people. While this is still debated, current consensus is that Acheuleans hunted large animals.
Caves sites where animal bones are associated with artifacts and hearths provide convincing evidence of hunting. Unfortunately, caves are short-lived, and few survive from before 130,000 years ago. The exception is Zhoukoudian, but even this site contains hyena bones and coprolites, and bones damaged by hyena teeth. The cave of La Cotte de St. Brelade, in layers between 186,000 and 127,000 years old, has numerous Mousterian artifacts, together with bones of at least 20 mammoths and five woolly rhinoceroses associated with early Homo neanderthalensis
. Human butchering is implied by cut marks and skeletal part representation.
Key Discovery: The Discovery of the Turkana Boy
Key Discovery: The Acheulean Hand Axe Tradition
Key Controversy: The Dating of Javan Homo erectus
Key Controversy: Did Homo ergaster
Disperse Partly by Boat?
Key Controversy: How Did Human Fossils Reach the Sima de los Huesos?
Key Controversy: Acheulean Big-Game Hunters?
Key Method: Electron Spin Resonance (ESR) Dating
Key Method: Luminescence Dating
Key Method: Uranium-series Dating
Key Site: The Gran Dolina TD6 and the History of Cannibalism
Key words and terms Chapter 3
Sites - in order of discussion in text
East Turkana, West Turkana, Kenya
Olduvai Gorge, Tanzania
Koobi Fora, Kenya
Nariokotome III, Kenya
Karari Escarpment, Kenya
Peninj (Lake Natron), Tanzania
Melka Kunturé, Ethiopia
Kalambo Falls, Zambia
Trinil, Java, Indonesia
Sangiran, Java, Indonesia
Ngandong, Java, Indonesia
Sambungmacan, Java, Indonesia
Zhoukoudian, Locality 1, China
Lontandong Cave, China
Nihewan Basin, China
Gran Dolina, TD6, Atapuerca, Spain
Dmanisi, Republic of Georgia
Sima de los Huesos, Atapuerca, Spain
Fontana Ranuccio, Italy
Castel di guido, Italy
La polledrara, Italy
Gesher Benot Ya'aqov, Israel
Terra Amata, France
Ariendorf 1, Germany
Le Lazaret Cave, France
La Baume Bonne, France
Montagu Cave, South Africa
Swartkrans cave, South Africa
Cave of hearths, South Africa
Prezletice, Czech Republic
Pech de l'Azé, France
La Cotte de St. Brelade, Jersey
Duinefontein 2, South Africa
Twin Rivers, Zambia
Berekhat Ram, Syrian/Israeli border
KNM WT 15000
D2700, 2280, and D2282
Olduvai hominid 9
Buia and Daka skulls
G.H.R. von Koenigswald
Hallam L. Movius
electron spin resonance
sediment accumulation rate
Hominin morphology terms
forehead (frontal bone)
forward projecting nose
constricted birth canal
tall, slim, heat dissipation
Acheulean cultural tradition
hand axes, cleavers, large bifacial ovals, triangles
Early vs. Late acheulean
colonization of hot, arid, seasonal environments
colonization of cold, glacial environments
early dispersion vs. technological bottleneck
lava pebble figurine
incised elephant tibia
hunting and scavenging
skeletal part representation