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100
circa 12000 B.C.
It is believed that paleoindians crossed Beringia (todays Bering Strait) from Siberia to North America. During the late Pleistocene Epoch, when the colder climate froze seawater in ice sheets around polar caps causing sea levels to drop, -
105
hunter gatherers circa 12000 B.C.
live in small groups
usually nomadic
little relative impact
5-10 million people -
Aug 24, 1000
early Agricultural revolution
people started growing crops :D
less nomads and more livestock
only culture is native americans
started towns -
late agricultural revolution
pilgrims land.
they brought crops and the plough
made more towns
forest devestation to build houses -
frontier era
when coloniels arrived 1607 resources seemed never ending
they used as much as possible
high enviromental destruction
low pollution
near extinction of american bison -
industrial revolution
switched from wood to fossil feuls
high pollution
bad working conditions
better medical practices
better farming and more people -
Period: to
coservation era
major conservationists is henry david thoreau, john muir, and theodor roosevelt -
first wildlife refuge established
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killer fog in london
700 dead -
yosemite national park established
government declares countries frontier closed -
Period: to
timber cutting banned on large public lands
-
u.s. forest service created
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svante arrhenius
proposes global warming due to fossil feuls -
solar conservation act
sun powahhhhhhh -
federal food drug and cosmetic act
it was passed!!!!!!!!! -
atomic energy act
atom power -
water pollution act
no mo toxic wata -
Period: to
Environmental Era
a movement to reduce pollution and stop the degredation of habitats across the united states.
richard nixon creates the EPA and endangered species act in the 70s -
pollution
cuyshoga river catches fire. -
energy conservation act
promotes energy conservation -
Bow and Arrow introduced to American Cultures
allowed hunters to more effectively kill animals, and posed a greater threat to all of the American Environment
