Title: Big Bang from 10-15 billion years ago
1A Short History of the Universe and Planet Earth
- Big Bang from 10-15 billion years ago
-
2About 5 billion years ago Earth formed out of
gases and dust We are stardust. We are golden.
We are billion year old carbon Joni Mitchell
3First life forms about 4 billion years ago-single
celled organism
4Pleistocene-emergence of first human lineage
Australophithcus 5 million years ago
5First modern humans homo sapiens about 50,000
years ago, differentiated from Neanderthals.
6Evolution of Human Society
- For the first 30,000-40,000 years or so human
beings lived exclusively in hunting and gathering
societies or bands. - Bands- depend on hunting, fishing, or the
gathering of wild plants to provide basic food
needs. The hunting and gathering economy demands
extensive land, permanent settlements rarely
possible. - people have to keep moving whenever the local
food supply becomes depleted.
7- Possessions are limited to what can be carried,
and dwellings are very simple huts and tents.
8Hunting and Gathering Societies
- They are egalitarian.
- Little specialized knowledge
- Children socialised in all roles involved in
everything - Gathering is done more frequently/ hunting is
sporadic (depends on availability of game) - Completely dependent on environment.
- original affluent society - all need were met,
lots of leisure time.
9Did Early Human Beings or Indigenous Peoples in
more recent times, live in harmony with the
environment?
- Human Beings-in-Nature vs Human
Beings-above-Nature. - Pleistocene Overkill.
- Use of Fire
10Pleistocene Overkill
- Pleistocene (1.8 million-10,000 years ago)
- Mammoths and their cousins the mastodons,
longhorned bison, sabre-toothed cats, giant
ground sloths, and many other large mammals in
North America. - Native horses and camels galloped across the
plains of North America. Great teratorn birds
with 25-foot wingspans stalked prey. - Around the end of the Pleistocene, all these
creatures went extinct (the horses living in
North America today are all descendants of
animals brought from Europe in historic times).
11Pleistocene Overkill II
The Pleistocene also saw the evolution and
expansion of our own species, Homo sapiens, and
by the close of the Pleistocene, humans had
spread through most of the world. According to a
controversial theory, first proposed in the
1960s, human hunting around the close of the
Pleistocene caused or contributed to the
extinction of many of the Pleistocene large
mammals
12Pleistocene Overkill III The Evidence
-
- 1)Large animals, over 100 lbs,suffered far more
than small ones. If climate, you would expect
small animals to suffer as much. - 2) extinctions occurred in each particular
location soon after the arrival of human beings. - 3) The large mammals that survived and are still
with us span 12 genera moose, white-tailed and
mule deer. among hoofed animals. But North
America had 45 genera of large animals. We lost
four types of giant sloths .
- Large mammals that survived were largely of
Eurasian origin and were accustomed to human
beings. Survivors like moose are solitary, or
like bison have unpredictable migrations.
1319th Century Evidence
- .capable of abusing their environments by, for
example, driving great numbers of large game
animals off cliffs and using only a few. And
given more powerful technological means, such as
guns, they were not necessarily better stewards
of nature than people in industrial societies
p. 41 Harper
14HOWEVER
- Native peoples lived much closer to nature and
depended directly on nature for their
livelihoods. - There are important lessons on respect and
reverence for nature in many indigenous religions
and traditions.
15Indigenous Peoples and Fire
- Villages moved every 15 years-20 years, when
local resources were exhaustedshifting
agriculture /slash and burn. Created a mosaic of
secondary succession. - 10-20 of forests in clearing or secondary
succession. - Tallahassee means old fields ie secondary
succession areas.
16Ancient Civilization The Rise of Agriculture
- Neolithic- beginning of agriculture 10,000 bp.
domestication of plants and animals. Change, via
ARTIFICIAL selection, from wild forms to a more
useful form, such as wolf to dog, grasses to
wheat, etc. - Catal Huyuk, Turkey, 9000 bp. A town of 10,000
people.. Not quite a city, no division of labor,
occupied by farmers, decentralized. Individual
residential structures with ovens, benches,
storage areas. But had painted murals showing
vultures attacking headless men, volcanoes,
hunting. A rich symbolic life.
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18Mesopotamia Babylonians, Sumerians
Environmental Degradation
- In Mesopotamia, irrigation was essential for crop
production. - Rivers were higher than the surrounding plain
because of built-up silt in the river beds, so
water for irrigation flowed into the fields by
gravity. Once the water was on the fields, it
could not readily drain away because the fields
were lower than the river. As water evaporated,
left its dissolved mineral salts behind. Over
time, soil became toxic and no longer supported
crops. - By about 2300 B.C., agricultural production in
Mesopotamia was reduced to a tiny fraction of
what it had been. Many fields were abandoned as
essentially useless. Mesopotamian cuneiform
tablets tell of crop damage due to salts.
19- As late as 7000 BC, the Tigris and Euphrates
valleys were covered with productive forests and
grasslands. But increased salt buildup in the
soil from irrigation evaporation in a hot climate
caused food production to decline an estimated
42 per hectare between 2400 and 2100 BC.
Environmental degradation was clearly one of the
factors, with climate change, invading armies.
(p. 43 Harper)
20Chaco Canyon-New Mexico (800-1100 AD)
21During the middle and late 800s, the great houses
of Pueblo Bonito, Una Vida, and Peñasco Blanco
were constructed. These structures were often
oriented to solar, lunar, and cardinal
directions. Sophisticated astronomical markers,
communication features, water control devices,
and formal earthen mounds surrounded them
22By 1050, Chaco had become the ceremonial,
administrative, and economic center of the San
Juan Basin. Dozens of great houses in Chaco
Canyon were connected by roads to over 150 great
houses built throughout the region.
23"public architecture" that were used periodically
during times of ceremony, commerce, and trading
24But it CollapsedDisappeared. Why????
- A very arid environment, totally dependent on
rain (but had overcome with careful irrigation). - Probably overpopulation for available resources,
combined with drought, very fragile environment.
25Mayan Civilization (400 BC-1150 AD)
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27Collapse of the Mayan Civilization
- Theories
- over-population
- extensive warfare
- revolt of the farmer/laborer class
- drought
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29Environmental Stress probably one of several
causes
- Now known that Maya region suffered extensive
deforestation during the Classic Maya period. - Many soils in region marginal.
- Also known there was a severe drought late in the
Classic Mayan period.
30World Views in Agricultural Societies
- Cognized environments of hunter-gathers was a
natural living wilderness. Man-in-nature. - Cognized environment in agricultural societies is
a garden. Human beings begin to push the
wilderness away
31All of these civilizations lasted hundreds of
years before collapsing. Are we immune from this
history? Are we stressing our environment in the
same way they did? Could a change in the
environment like global warming cause widespread
failures of agriculture?