A Short History of the Universe and
Planet Earth
•
Big Bang from 10-15 billion years ago
About 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
First life forms about 4 billion years ago-single
celled organism
Pleistocene-emergence of
first human lineage
Australophithcus 5 million
years ago
First modern humans: homo sapiens:
about 50,000 years ago, differentiated
from Neanderthals.
Evolution 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.
•Possessions are limited to what can be carried,
and dwellings are very simple huts and tents.
Hunting 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.
Did 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
Pleistocene 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).
Pleistocene 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
Pleistocene 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, whitetailed 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.
19th 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
HOWEVER
• 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.
Indigenous Peoples and Fire
• Villages moved every 15 years-20 years,
when local resources were
exhausted…shifting 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.
Ancient 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.
Mesopotamia: 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.
• 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)
Chaco Canyon-New Mexico (800-1100 AD)
During 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 astronomic
markers, communication features, water control devices, and formal
earthen mounds surrounded them
By 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.
"public architecture" that were used periodically during times of ceremony,
commerce, and trading
But it Collapsed………Disappeared. 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.
Mayan Civilization (400 BC-1150 AD)
“Collapse of the Mayan Civilization”
Theories
• over-population
• extensive warfare
• revolt of the
farmer/laborer
class
• drought
Environmental 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.
World Views in Agricultural Societies
• Cognized environments of hunter-gathers
was a natural living wilderness. Man-innature.
• Cognized environment in agricultural
societies is a garden. Human beings
begin to push the wilderness away
All 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?