World Prehistory: Class 4

ã Copyright Bruce Owen 2000

• Climate and Environment in the Pleistocene
• Pleistocene somewhat arbitrarily starts at 1.6 mya
• How is climate reconstructed?
• oxygen isotope ratios of foraminifera from sea cores
• Overall temperature trend in the last 50 my or so: very variable, but net downward trend
• During the Pleistocene: many cold periods and warmer periods
• The Holocene (modern era) may just be one of these warmer periods
• why do ice sheets expand?
• weight in interior pushes edges outwards
• how was geography different during cold periods?
• 30% of land covered by glacial ice
• vs. 10% today
• lower sea level (100 - 150 m) due to water tied up in continental ice
• Fagan gives a maximum of 197 m (650 feet!) lower
• exposes broad areas of land in what is now ocean
• linking many islands to each other and to the mainland
• allowing animals and plants to spread, which were then isolated as warming raised sea level
• these isolated populations were then free to evolve off in their own directions...
• cause of climate variation?
• cyclical patterns in earth's orbit eccentricity and precession of axis change amount and distribution of sunlight falling on the surface
• 20,000 year, 40,000 year, and 100,000 year cycles
• "Milankovitch forcing"
• this accounts for the short-term jiggles, not the overall cooling trend
• the short-term jiggles are very important, though!
• Lower Pleistocene: 1.6 mya to 0.73 mya (730,000 years ago)
• arbitrary end of period at convenient geomagnetic reversal
• Middle Pleistocene: 730,000 - 128,000 years ago
• Human evolution and migrations played out in climates and sea levels that were very different at different times
• but they would not have seemed to be changing to the people at the time!
• Homo sapiens appeared during the Middle Pleistocene or early in the Upper Pleistocene depending on what evidence you believe; we won't deal with that today
• Homo erectus
• H. erectus appeared around 1.9 mya, lasted to about 0.2 mya (200,000 BP) (1.7 million years with minimal change)
• almost certainly evolved from H. habilis or a close relative
• almost certainly evolved in Africa
• at the time, there were also several other bipedal hominids around
• one or more gracile australopithecines
• several robust australopithecines
• all were extinct by 1.0 mya, leaving H. erectus as the only hominid
• Physical development of H. erectus:
• brain about 1000 cc, larger than H. habilis (680 cc), smaller than H. sapiens (1400 cc)
• massive browridges, low forehead
• protruding face, heavy lower jaw, no chin
• body essentially like modern humans, but more robust
• cranial capacity constant from 1.5 mya to 0.5 mya, then increases a bit in the last few hundred thousand years before the species disappears
• maybe associated with development into H. sapiens
• Cultural innovations by H. erectus:
• stone tools clearly made in specific forms
• the prototypical H. erectus tool is the Acheulian handaxe
• but some H. erectus populations, especially the Asian ones, did not make these
• definite evidence of "systematic" hunting of large game
• wooden spears
• use of fire
• probable huts or shelters
• The Paleolithic period
• Paleolithic: only flaked stone tools
• Neolithic: addition of ground stone tools
• Paleolithic subdivisions:
• Basal Paleolithic
• Oldowan tools
• 2.6 - 1.8 mya
• Australopithecines and H. habilis
• Lower Paleolithic
• Acheulian tools (esp. handaxes)
• 1.8 - 0.2 mya
• H. erectus
• spread out of Africa to Asia and Europe
• use of fire by 500,000 BP
• definite hunting of big game by 200,000 BP
• huts or shelters by 200,000 BP
• H. erectus's tool "industry"
• The Acheulean handaxe
• "signature tool of the Lower Paleolithic"
• but not in Asia, and not in northeastern Europe
• why not?? Maybe this should tell us something...
• a teardrop-shaped, flattish, more heavily flaked core tool (compared to an Oldowan pebble chopper)
• presumably used for many tasks
• cutting meat, sawing wood, digging, pounding, boring
• probably hand-held, not hafted
• none are "waisted" for hafting
• no hafting wear noted
• composite tools seem to appear much later
• but for most of these, why not just use flakes?
• consistent, symmetrical shape in different sizes implies planning, visualization, control
• from a few inches to over a foot long
• variations in pointiness, proportions, etc.
• almost always worked all the way around, bifacially
• some sub-traditions sometimes required using a stone "hammer" to rough out the shape, then a wood or bone "billet" to knock off the finishing flakes
• this clearly requires some intellectual abilities
• but since they did not make any more specialized tools, or haft them, for hundreds of thousands of years, their creativity must have been a bit limited
• oldest ones from Konso-Gardula, southern Ethiopia: 1.9 mya (right when H. erectus is first appearing)
• in northern France, St. Acheul:
• series of river terraces, oldest high on valley walls, youngest lowest in valley
• due to downcutting with each glacial melting (interstadial)
• handaxes from the highest (oldest) terraces
• cruder
• made with hard hammer
• handaxes from the lower (younger) terraces
• better made, more regular
• made with soft hammer, producing thinner, wider flakes with better control
• also cleavers, various flake tools such as scrapers, burins, borers
• some sites have no handaxes ("Clactonian" assemblages)
• but are shown to be contemporary in Europe, and found in same levels at Olduvai
• maybe a functional difference between sites?
• or handaxes only made when good material was available?
• also definitely made wooden spears, clubs, etc.
• Schoningen, Germany: 3, maybe 4 wooden spears found with stone tools and animal bone, 400,000 BP
• Kalambo Falls: 200,000 BP to present, southern Africa
• extremely long sequence of occupations, over 200,000 years to nearly the present
• calm river flood / lake water deposits, waterlogged
• unusual conditions preserve wood and plant remains, but dissolve bone!
• lowest level has late Acheulean living surfaces
• leaves, nuts, seeds, fruits
• remind us of plant component of diet
• wooden club, sharpened wooden spike
• charred logs imply use of fire
• Clacton, England, 200,000 BP, wooden spear point
• H. erectus spread out of Africa probably shortly before 1.8 mya
• earliest dates outside Africa are 1.8 mya in Georgia (Dmanisi)
• but maybe this one is as recent as 900,000 BP
• and 1.7 mya in Indonesia (Trinil) (probably; some disagree with this date)
• 1.5 mya in Israel, but must have already been in the region by 1.8 mya if the other dates are correct, since it is on the route between Africa and Asia
• i.e. spread could have been very rapid (depending on whether the early dates are correct)
• rapid in geological terms
• but not fast at all in human terms
• just 10 miles per generation (at 20 years per generation) would get hominids from Africa to Indonesia in only 20,000 years (0.02 my), fast enough to look instantaneous by current dating methods
• why did they move towards Asia?
• "pump" effect of the alternately green and drying Sahara?
• concept of the random walk
• with limits set by boundaries of favorable ecological zones
• that is, they moved in all directions, but some of them happened to be towards Asia
• as the climate allows the spread of plants and animals, exactly the same would have happened with H. erectus
• so, why did H. erectus spread out of Africa when H. habilis and the australopithecines had not?
• the environmental conditions were nothing that had not happened before...
• better tools, technology, cleverness for getting food in more different environments?
• maybe developed the intellect, tools, and/or social behavior to successfully hunt herding animals and/or reliably find frozen carcasses in winter?
• as Fagan discusses on pp 85-86
• fire and clothing allowed them to live in seasonally or permanently colder climates?
• fire is also good for driving animals for hunting
• cooking food to make more plants edible
• keeping away predators
• but it is very hard to document the casual use of fire...
• Trinil (Java)
• why were people looking for a "missing link"? What was it going to tell them?
• early H. sapiens fossils known from Europe
• but no intermediate forms between apes and them known
• expected to prove the line of descent
• and show the order to changes in it
• why did Eugene Dubois think that Southeast Asia was a good place to look for the "missing link"?
• Darwin and Alfred Russell Wallace suggested that humans evolved in a "warm, forest-clad land"
• Wallace wrote about Sumatra and Borneo, which were that plus they had orangutans, potential descendents of the shared ape-human ancestor
• Limestone caves would preserve remains
• Surface deposits had not been scraped off by Pleistocene glaciers, as in northern Europe
• Java man = Solo man = Pithecanthropus erectus = H. erectus from Trinil
• ironically, not in a cave site at all, but river gravels
• how did H. erectus get to the island of Java?
• it wasn't an island then, due to lower sea level -- connected by the Sunda shelf
• where might many early sites be, then? Under the sea.
• dates of H. erectus in southeast Asia at least 700,000 years ago; maybe up to 1.8 mya
• what about stone tools?
• none found
• maybe they weren't made, but bamboo, etc. used instead?
• Zhoukoudian (= Choukoutien = Sinanthropus pekinensis = Peking man = H. erectus)
• near Beijing
• a huge cave, 140 m long, 40 m wide, 40 m high
• gradually filled with rock fragments cemented by limestone deposits (breccia)
• encasing any bones, tools, etc. left there
• occupied (probably not continually) by H. erectus from 460,000 BP to 230,000 BP during the process of gradual accumulation of material on the cave floor
• 230,000 years of people visiting the same cave!
• bones of at least 40 individuals
• cultural evidence
• "dense layers of ash"
• suggest controlled use of fire (why not wildfires, etc.?)
• stone tools
• made from quartz, sandstone, crystal, flint
• material brought in from other places
• flakes, scrapers, choppers, but no handaxes
• what might this mean?
• regional cultural difference?
• i.e. "Chinese" H. erectus had a different lifestyle and technology from African and Southwest Asian H. erectus, just as modern people have regional cultures?
• Handaxes represent learned culture, not wired-in behavior of H. erectus?
• crude, but improve in technology towards top of deposits
• again, are we missing an important part of the technology that would have been made from bamboo and other perishable materials?
• Fagan discusses this twice as a fact, but there is no confirmation...
• animal bone
• especially an extinct deer
• specialized deer hunters?
• "charred hackberry seeds"
• gathered plants cooked in the cave?
• or just naturally burned plant material?
• why don't we know more about the cultural evidence?
• quarry-like excavation methods
• hominid fossils
• H. erectus, 6 skullcaps, teeth, mandibles, femora, etc.
• gradual increase in cranial capacity from 900 cc to 1100 cc during the occupation of the cave
• what happened to the fossils?
• lost at the outbreak of WWII, but we have good casts...
• The First Europeans
• Despite H. erectus moving into Asia by 1.8 mya, the oldest sites in Europe only approach 800,000 BP
• maybe because Europe was too cold and glaciated to occupy until hominid culture was more complex?
• Gran Dolina, Spain: probably a bit over 800,000 BP
• flakes of sandstone (!), limestone (!), quartzite, flint
• no handaxes (what does this mean?)
• animal bone
• at least four hominid individuals, including a child and an adolescent
• Isernia, Italy: a bit over 730,000 BP
• some tools and animal bones...
• a few other possibilities
• but by 400,000 BP, many sites in Europe
• Verteszollos, Hungary
• thousands of small tools made on 1" pebbles
• charcoal and burned animal bone imply use of fire
• hominid skull fragments
• Evidence of behavior
• was H. erectus really a human-style hunter?
• they butchered a lot of large animals
• known from bone-and-tool sites
• but so did australopithecines and/or H. habilis
• they made wooden spears, at least by 400,000 BP
• but not necessarily for hunting
• they lived in cold, steppe environments that probably required hunting for survival
• or could they find enough naturally dead animals to scavenge?
• maybe they just drove animals into swamps, off cliffs, burned off grass, etc...
• Fagan says that hunting large animals would require considerable social skills; others have suggested it even requires language
• what about hyenas, lions, even baboons and chimps that sometimes hunt?
• Torralba and Ambrona, Spain
• 350,000 BP, cold period (Fagan says 400,000 or 200,000 BP)
• on probable seasonal animal migration route
• marshy area
• Acheulean (=Acheulian) handaxes
• other tools of bone, ivory, and wood (?)
• large animal bones, mostly elephant
• 1 at Torralba, 30-35 at Ambrona
• clearly butchered
• crania broken open to get at brains
• no hominid fossils
• debate about whether these are hunting or scavenging sites
• did they drive the animals into the marsh and kill them, or just find them trapped or already dead in the marsh?
• Terra Amata: 300,000 BP, cold period
• found by accident during bulldozing for an apartment block
• French coastline of Mediterranean, near a river mouth
• a near-shore camp with windbreaks, hearths, cooking debris, tools
• unusual in that it has an intact living area preserved (maybe)
• original interpretation by Henry de Lumley:
• large oval huts with slightly concave floors
• branches stuck in the ground around the depressions, leaning inwards, bases supported by rocks
• central posts to hold up the ceiling\
• some had a central hearth
• floors full of bones, plant debris, coprolites
• thought to have been rebuilt in a series of visits
• now there are doubts
• refitting studies found flakes and bone fragments that fit together from levels up to 30 cm apart
• thus there may not be a series of thin, separate floors
• how might flakes get so far separated vertically?
• it isn't really so far...
• so the features that de Lumley put together to see huts could have been fortuitous selections out of a mixed-up mess of postholes, hearths, midden, etc.
• that is, people lived there, but the architectural reconstruction may be imaginary
• tools
• crude Acheulian, including a few handaxes
• mostly local material, but a little imported
• debitage found scattered around clear area, like where a flintknapper was sitting...
• unless this, too, was imagined by the excavator
• diet
• red deer, elephant, rhino, mountain goat, wild boar, wild cattle
• just a little fish and shellfish
• Fagan suggests that H. erectus's failure to use a lot of seafood or to hunt birds indicates limited intellectual ability
• maybe...