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Geology
The Pleistocene was known for its ice
ages. An ice age is a time when many glaciers cover many
parts of the earth. Scientists have come up with many
reasons for an ice age:
- The earth right now is on an
approximate tilt of 23.1 degrees. Most scientists now
support the theory that during earth' s many past ice
ages, the earth was not on a tilt. If this happened,
sunlight would not reach the poles, allowing much snow to
accumulate. Once enough snow accumulated, the pressure of
the glacier would cause a thin, slippery layer of water
to form underneath the colossal ice sheet. When it moved
southward, the sun melted the glacier, creating a thicker
water layer underneath the ice. This is the most
supported theory.
- Another theory is that there was a
lot of volcanic activity during this time, which caused a
substantial amount of dust and particles to fly in the
air. This, in turn, made the earth cooler, allowing
glaciers to form.
- Today, our orbit is almost circular.
Some scientists say that in the ice ages, earth\rquote s
orbit was more like an ellipse, and when earth was
farther away, ice caps enlarged and glaciers could
form.
Whatever the cause, animals of the
Pleistocene had to stay tough to survive.
Animal Life
All living organisms had to cope with the
ice age. Mammals evolved through adaptation. They adapted in
the following ways:
- A covering of hair. This kept in the
heat and made them warmer.
- They became smaller. Being smaller
requires less food and it allows less heat to
escape.
- Animals migrated equator-ward. There
it was warmer, and they could get a bite to
eat.
- Or they died out. That isn't really
adapting, but that's what some animals did.
Plant Life
During the Pleistocene Epoch, Plants also
evolved with the climate change. During the warmer,
inter-glacial period, woodlands
were dominant. As it got colder, grasses
emerged. During the Ice ages, tundra was the main
vegetation.
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All animals needed to adapt in the
Ice Ages.
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