Prehistory

Beginnings of human civilization

• Humans have existed back in time for millions of years
• Controversy beyond the scope of this class
• To understand civilizations like Mesopotamia, we need to have some context

Ice Ages

à Summary and references at: Center for the Study of Carbon Dioxide and Climate Change, “Earth’s Climactic History: The Last 2,000,000 Years”

• 10 ice ages in last one million years
• First proposed in 1992 -- “Some researchers have suggested that at this time (about 600-800 million years ago) the Earth was frozen solid -- it was a 'Snowball Earth'…. there would remain a narrow belt of open water around the equator, in which primitive marine organisms could have taken refuge.”
• Critics are out there – 2002 evidence to disprove theory? (really against ‘hard’ snowball theory)
• 10 ice ages in last million years before that
• 10,000 year interglacials
• at times, as earth’s land mass was closer to equator (Pangea), ice covered places like South America, New Guinea,, Australia eastern Africa, and the Andes Mountains
• during last ice age, there were about 20 times in which temperatures list rapidly, then slowly cool, and then rapidly return to glacial conditions (lasts 50-2000 years)

• 11,000 years since the last glacial period
• some say we’re overdue
• others – this warm period could last 70,000-100,000 years
• still others - possible good news: no more ice ages for tens of millions of years
• “Ice ages may be caused by our Solar System's passage through our galaxy's spiral arms during our orbit around the centre of the galaxy.”(story)

• Ice can be as much as one or two miles thick
• Most recent ice age (Wisconsin glaciation):
• Starts: 70,000 ya [draw timeline indicating Jesus’ birth; Moses; Abraham; Noah; etc.]
1. Reaches Maine c. 25,000 ya

§ Peak: 18,000 ya

§ avg. temp. 18 degrees lower than today

§ heavy snows in Arctic

§ ice sheets move south at about 300 ft./yr.

§ Sea surface temperatures were lower than now (even compared to chilly Maine waters!)

§ Higher wind speeds over the oceans (50-80% increase)

§ Climate is much drier during last ice age

1. Large sand dunes in Central America and sub-Saharan Africa

§ Glacial limit is marked offshore by Long Island, Martha’s Vineyard, Nantucket, and deposits now underwater on Georges Bank

§ Also less carbon dioxide in the atmosphere, so land plants suffer

§ Ice retreated rapidly in some places

1. In Michigan, the ice retreated and when it was only 5-10 miles away, forests grew, with trees up to 30 feet high. Then 145 years later, ice melted and flooded the forest

§ Maine Ice Age geology

1. The sand, gravel, and other unconsolidated sediments that cover much of Maine are largely the product of glaciation.

2. Under Kennebec River as it crosses Bath-Woolwich, there is marine clay – under sand and gravel -- that was deposited as the glaciers melted c. 12,000 ya

3. “Shells and shell fragments of marine mollusks were found in some samples of this clay. Under the marine clay, some isolated pockets of sandy glacial till were encountered along the section. Glacial till, which is typically a heterogeneous mixture of sand, silt, clay, and stones, but may be predominantly composed of sand in some cases, was deposited directly by the glacier.”(details)

4. Weight of the glacier sank the Maine coastline from 17,000-12,000 ya

1. In Topsham, oceans were 250 feet above present-day sea level

5. Glaciers carved out spaces, and when land “sprung” up, it locked lakes from ocean

à “Lake Levels and Climate Change in Maine and Eastern North America during the last 12,000 years” | Maine Geological Survey e-books

6. Found mammoth, walrus, and seal remains in glacial sediment

§ ocean levels drop about 400 feet as ocean water frozen up in the water

1. Exposed land bridges -- Bering Strait, Japan and mainland China and Korea

§ forms lakes, changes the paths of rivers, erodes land, and deposits sand, gravel, and rocks along the glaciers' paths

§ Ice Age Animals:

1. Wooly rhino (11 ft long), cave lion (11.5 ft long), glyptodon (armored armadillo – 10 ft long/5ft tall), mammoth (up to 13ft long), mastadon, Irish elk (10ft tall/antlers 11ft across), saber-toothed cats (such as smilodon, fierce predator at 4-5 ft long) (more)

§ Cave dwellers draw pictures of some of these animals

1. Oldest yet discovered - northern Italy - between 32,000 and 36,500 years old

1. images of an animal and a human-like creature.

2. Cave paintings in France and Spain dating to c. 30,000 years

1. Cave discovered in France in 2001:

1. “Experts describe a 12-metre-high (40-foot) cave, its walls covered in drawings of mammoths, rhinoceroses, horses, human beings and some strange beasts with long, gaping snouts, which scientists have yet to identify.” (source)

3. In France c. 15,000 ya, lifelike human faces painted on floor of caves (more), as well as stick figures painted on cave walls that date back 30,000 years

4. South African engravings of geometrical patterns date back 70,000 years (more)

• Fire as early as 3 mya
• “They rarely lived beyond the age of 35, not because of hardship, but more probably because of disease, since even minor cuts could cause fatal infections.”
• Handaxes by 1 mya (source)
• Making houses by 500,000 years ago
• Had to fight animals for these shelters before humans learned to make houses/tents
1. “The cave bears, Ursus spelaeus and their cousins Ursus deningeri, were fierce, 20-foot long versions of Grizzly bears with huge teeth and razor sharp claws. Until Neanderthals, and the later Cro-magnons appeared on the scene in Europe and the Mid-east, these giant carnivores infested every cave from sea level to altitudes near 10,000 feet.”
2. “Cave bears inhabited caves in Europe throughout the Pleistocene, from about 300,000 to 15,000 BC, disappearing by the end of the last ice age.” (more)
1. lived in packs
2. coordinated efforts of many fighters
• 500,000 ya - “Japanese archaeologists have uncovered the remains of what is believed to be the world's oldest artificial structure, on a hillside at Chichibu, north of Tokyo.”
1. “Before the discovery, the oldest remains of a structure were those at Terra Amata in France, from around 200,000 to 400,000 years ago.” (more)
2. more on other Ice Age homes
• language – 200,000 – mutations on gene FOXP2
• “They found slight but crucial changes to the chemical sequence of the gene that happened during the passage of time….They found slight but crucial changes to the chemical sequence of the gene that happened during the passage of time…Changes to two single letters of the DNA code arose in the last 200,000 years…”
• “’The idea is that these changes gave some people an advantage because they were able to communicate more clearly,’ says co-author Simon Fisher of the Wellcome Trust Centre for Human Genetics at the University of Oxford, UK.”
• Not THE language gene; just the first discovered (BBC, 13 August 2002)
• “A mounting body of research suggests that the mutant gene conferred on human ancestors a finer degree of control over muscles of the mouth and throat, possibly giving those ancestors a rich new palette of sounds that could serve as the foundation of language.”
• “the human version of the gene, in its critical segments, differs by only three molecules, out of 715, from the version carried by mice and by just two molecules from the version carried by chimpanzees.”
• Replaced more primitive form of gene within 10-20,000 years
• “…the mutations in FOXP2 apparently changed the shape of the relevant protein in a way that somehow permitted greater complexity in the parts of the brain controlling movement of the face, throat and voice box.” (Washington Post, 14 August 2002)
• “Language is unique to humans: chimpanzees can be trained to communicate using a complex set of symbols, but they can pronounce only a handful of words because they cannot make the required facial movements.” (Nature, 15 August 2002)
• Around 40,000 years ago, humans started wearing jewelry
• Theory: Shell beads gave people a sense of identity
1. “Beads and decorations were a way of expressing individual identity and of determining which social group a person belonged to, or their status within that group.” (story)
• 40,000-35,000 – earliest art found in Zambia, but pigments used much earlier (body decoration?)
• “Archaeologists in Zambia have uncovered evidence that early humans used paint for aesthetic purposes far earlier than previously thought. The team found pigments and paint grinding equipment believed to be between 350,000 and 400,000 years old. The oldest pigments previously found were 120,000 years old and the oldest known paintings are just 35,000 years old…It is likely that the stone age inhabitants used the colours, which range from yellow to purple, to paint their bodies during hunting rituals, ceremonies and other social events.” (more)
• “Woven clothing may date back at least 27,000 years, according to archaeological evidence left by stone age hunter-gatherers. Previously it had been thought that weaving had been invented by settled farmers just 5,000 to 10,000 years ago. The new information means features on figurines thought to be prehistoric hairstyles are actually the first known hats.” (more)

• around 16-14,000 years ago, drew star maps on cave walls, near drawings (more)
• around 11,000-10,000 years ago, ice sheets (jncluding those in Maine) begin to retreat
• climate moderates
• agricultural revolution well under way by end of Ice Age (Neolithic – New Stone Age)
• From mobile hunter-gatherer societies (sign of Paleolithics – Old Stone Age) to settlements in fixed areas
1. As climate moderates, it is warmer and wetter, making it easier to get food
• Evidence from Syria that “the systematic cultivation of cereal crops such as rye had already begun around 13,000 years ago” (more)
• Transition from use of wild crops (wheat, etc.) to farming
• Expect similar evidence elsewhere in Fertile Crescent
• Anthropologists believe agriculture probably started in the Middle East and then swept into Europe about 8,000 B.C.
1. “The UCL researcher added: ‘All Europeans have hunter-gatherer genes, but they also have Near East farmers' genes. There are clear differences between regions in Europe. For instance, in Greece and the Balkans an individual has between 70-100% of genes from Near East farmers, but in western France and England as little as 10% of an individual's genes can come from the Near East.’ " (more)
• domestication of animals c. 9000 B.C.

§ dogs first, then sheep, goats, and cattle

• cultivation of crops

§ wheat, barley, then beans

• First villages and walled towns
• Jericho: first city, c. 9000 B.C.
• By 7,000 B.C., walls 10 ft. thick and 13 ft. high

§ About 2,000 people

• By 6,000 B.C., other cities have as many as 6,000 people
• First industries

Cloth – 7,000 B.C.

Metalworking – 7,000 B.C.

· Civilization (Latin, civitas “commonwealth” or “city”)

1. More complex

2. More control over nature

3. Rise in technology

4. Surplus food à increase in population and trade

5. Invention of writing

à Ancient civilizations, hitherto unknown to scientists, are still being discovered.

· In 2001, it was reported that an unknown civilization in Central Asia (Turkmenistan) using writing over 4,000 years ago.

· “The ancient society is believed to have herded goats, grown crops and made bronze tools and ceramics, all some 300 years after the pyramids of Egypt were built.”

· “It is not known what the people of the civilisation called themselves, so researchers have dubbed the society the Bactria Margiana Archaeology Complex (B-Mac), after the ancient Greek names for the two regions it covers.”

· “Archaeologists have uncovered "monumental structures", including multi-roomed mud brick buildings like apartment complexes.” (more)

· Speculation: Maybe this civilization influenced China in some way?