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 A105 Human Origins and Prehistory
Lecture 11

Homo erectus, the Acheulean, and early archaic H. sapiens

Homo erectus, 1.8-0.5 Mya (note that the ending date is uncertain) 
  The first fossils of this group are found in East Africa (Lake Turkana).  Beginning
of hominids that are more recognizably humanlike. 
    KNM-ER 3733 is one important specimen. 

H. erectus Important Characteristics 
 Earliest large bony nose 
 Cranial capacity 800cc - 1300cc; increases over time 
 Zygomatics receding, face becoming less robust. 
 Still no chin 
 Molars reduce, incisors increase in size (relatively larger than in A. africanus.) 
 Braincase : Expansion of nuchal area 
                   Skull is long and low 
                   Cranial bones are quite thick 
                   Nuchal torus, sagittal keel present. 
 
 

Postcrania:  KNM-WT 15000, the “Turkana Boy”  1.6 Mya. 
                   About 5’5” at 12 years old; perhaps 6 feet tall as adult. 
                   Modern limb proportions and joints. 
                   Small pelvic inlet. 
                   The bones are robust, with thick cortical bone. 
 
 

Why are cranial bones robust? 
       Chewing? 

       Stripping foods? 

       External?

Possible external forces acting on skulls 
    Aggression? 

    Hunting? 

    Defense against hard animal hooves?

What types of things cause modern people to break bones? 
   1. Falling 
   2. Being crushed 
   3. Collisions at high speeds 
 

 There is other evidence from the skeleton that H. erectus could have been a good hunter.  Overall body proportions are one piece of evidence. In modern people, long legs allow us to cover more distance per step, which is related to hunting strategies. 

 Hunting strategies of modern predators 
 1. Stalk and surprise.  Relied on by many cats. 
 2. Speed -- chase down prey.  Cheetah. 
 3. Endurance hunting -- pursue the prey to exhaustion.  Social carnivores like wolves and some human groups do this. 

Humans cannot use techniques based on speed; prey animals much too fast.  Instead of chasing at running speeds as wolves might, humans using traditional weapons (bows and arrows, etc.) walk their prey to death. 

How does H. erectus anatomy fit with hunting? 
1. Long legs -- long stride; slender build, as far as we can tell.  Long, efficient stride, efficient heat loss.  Could probably have used endurance hunting technique. 
 

 2. Molars, face less robust -- meat is easier to chew, does not require large molars. 

3. Large incisors, nuchal area -- may imply stripping meat, or use of teeth as tools. 

 4. Cutmarked bone is present at sites from the H. erectus time period -- does not prove hunting, only that meat was eaten, but still would be expected of hunters. 

5. Robusticity of skeleton would help offset dangers. 

 So, H. erectus certainly could have been an effective hunter; many believe that the shift to H. erectus could have been fueled by the addition of more meat to the diet, and that hunting shaped our lineage starting at this point.  Note, however, that some researchers believe that hunting did not become common until archiac H. sapiens.  For our purposes, we can say it was possible and even likely that H. erectus did at least some hunting. 

 With H. erectus, we have a hominid that, through hunting and/or scavenging, added more meat to its diet.  This was likely one of the factors enabling the migration out of Africa. 

When did hominids leave Africa? 
   Fairly soon after H. erectus evolved, but the exact date is still uncertain. 

                   1. Dmanisi, Georgia (former USSR) -- 1.7-1.8 mya 
                   2. Sangiran (Indonesia) -- 1.6 mya 
                   3. Some other claims as far back as 1.8 mya 
                   4. Ubeidiya, Israel -- 1.0 to as much as 1.4 mya. 
 
 

Asian Homo erectus Traits (differences from African specimens) 
    Brow ridge a different shape (straight, not curved) 
    Larger molars, more robust mandibles 
    Thickest cranial bones 
Cranial capacity: African average 850cc 
                          Javan average 900cc 
                          Asian average 1100cc 
                   This may have as much to do with time as location, however.
 

Zhoukoudian, important Chinese H. erectus cave site 
   More or less continuous occupation starting about 480 kya and continuing for hundreds of thousands of years 
  Several crania, mandibles 
  Tools, animal bones, evidence of burning (controlled fire? still controversial) 
  Temperate climate, somewhat like Indiana today; fruit not always available, but animals would have been. 

 Technology:  Recall, 1st appearance is 1.8 mya, during the Oldowan.  So, sites like FLK Zinj could have been the work of H. erectus.  About 1.6 mya, H. erectus began to
make a new kind of toolkit.  We call this the Acheulean industry, and it is the industry most often associated with erectus. 

 Acheulean Industry, 1.6 mya - about 200 kya 
 Second phase of the Lower Palaeolithic 
 First in Africa, then Europe, Near East, parts of Far East 
 Major change: addition of bifacial tools, such as the handaxe and cleaver. More kinds of retouched flake tools were also added at this time. 

 The handaxe is important because it is the first evidence that toolmakers had a specific form or mental template in mind when they did their flaking.  Not all H. erectus sites have Acheulean tools, however.  In some places, core and flake industries similar to the Oldowan continue to be made.  Many of these are now know to be contemporaneous with Acheulean sites.
 
 
 
 
 
 
 

Why are there two different kinds of sites? 
Different activities, different raw materials...
Multiple migrations would be one possibility.  Some very early European finds might support this, for instance, remains called Homo antecessor at Atapuerca in Spain.  These fossils date to 780-800 kya and are thought by some to be ancestral to Neandertals.  Though quite ancient, they have been placed in a different species from H. erectus. 
 

 Keep in mind that things may be as complicated in other parts of the world, but Europe looks more complex at least in part because it is better-studied. 
 

Homo erectus behavior 
   We know that hunting was probably at least a small part of subsistence, and can infer that some use of fire probably took place. 
  Hard to characterize the species as a whole, though, because we only have parts of 130 individuals spread over all of the Old World and from times spanning 1.8 million to less than 500,000 years ago. Sites are often ambiguously dated, too. 
  Wear polishes on tools indicate that, as with Oldowan, tools had a variety of uses, but specific tool forms do not go with certain uses. H. erectus did choose the best raw materials from those available locally. 

Some claims: 
      Elephant hunting, Torralba and Ambrona, Spain -- claim of hunting reduced now to claim that erectus took some elephant meat but likely did not kill the elephants. 
 

     Structures, Terra Amata, France -- "Post holes" found, said to be in a circle.  Currently this is disputed, and in any case the uniqueness of the site makes the claim suspect.  If erectus built structures, they were likely made in ways that do not preserve. 

     Schoeningen, Germany, 400kya -- wooden spears, possibly useable as throwing
 spears.  These are well-accepted; they do come at the very end of the erectus time period, though. 

   Cannibalism has been suggested due to damage on cranial bases, but this is now commonly thought to be due to carnivore activity. 

After H. erectus
    It is a complicated story, starting about 400 kya. 
    Many large-brained (>1250 cc or so) hominids with erectus-looking faces. 
     Two views: 1. If a big brain makes it H. sapiens, then we must extend this species back to 400 kya -- not terribly appealing given the primitive face, etc. 
                       2. If both big brain and modern anatomy are required, H. sapiens does not  appear until 100-70kya -- this does not really give justice to the changes that occur between 400-100 kya. 

So, a compromise: Primitive-faced hominids with big brains, living 400-35/32 kya are often called archaic Homo sapiens. Toward the end of this period, anatomically modern peope were present as well (about 100kya on).  Early archaic sapiens  in Europe are sometimes called Homo heidelbergensis; in Africa, H. rhodesiensis. 

 Though archaic sapiens existed everywhere, as we shall see, it is not agreed whether they evolved into modern sapiens everywhere; many scientists believe that only one population of archaic sapiens (one in Africa) gave rise to all modern people living today. 

Early archaic H. sapiens specimens 
                   Kabwe/Broken Hill, Zambia 
                   Petralona, Greece (350 kya; cranium 1230cc) 
                   Atapuerca, Spain (second group of hominids dates to 300 kya) 
                   Arago, France (300kya; 4 adults and 3 juveniles) 

Many early European archaics share characteristics: puffy maxilla, angled zygomatics. 

The best-known group of archaics comes toward the end of the archaic timespan, known as the Neandertals.