2 million to 11,000 BP : Pleistocene to Paleo
The Pleistocene Period began around 2 million years ago, as did the
Quaternary
Period which is still
ongoing.
Petrifaction of objects even this old need not occur if
the preservation conditions are suitable -
re: 2 million year old unpetrified Sequoia
and Bald Cypress found in
to the early Pleistocene include the
locust (Robinia pseudo-acacia), osage orange
(Maclura pomifera), red cedar
(Juniperus virginiana), Nyssa sylvatica, Vaccinium
arboreum, Ulmus alata, and Carpinus
caroliniana. Representatives of the Homo habilis
species have been found with stone tools from
around 1.8 million BP.
The Pleistocene was a period of dramatic temperature fluctuations with a
series of
glaciations concurrent with a low sea level, and
interglaciation periods concurrent with
a high sea level. The Blancan
interglaciation period began around 1.6 million years ago, at
which time Homo erectus was living in
standardized tool, existed 1.5 million years ago,
and evidence of fire usage in
been dated to this time. Around 1.3 million
years ago the
Nebraskan glaciation period began
around 1 million BP, and lasted about100,000 years.
Also around 1 million BP, Homo erectus migrated
into
existed from around 900,000 to about 700,000
BP, and between 900 and 800,000 years ago
Homo erectus arrived on the islands of
built up, and archaic Homo sapiens was
evolving. The Long Valley, CA eruption occurred
760,000 years ago, and the Kansan
Glacial age began around 700,000 BP. The
beginning of the Yarmouth Interglacial age. Java
Man (Pithecanthropus), lived around
500,000 years ago. Peking Man (Sinanthropus), lived about 350,000 years ago, the
Illinoisan
glacial age began near 325,000 BP, and
pre-Neanderthals lived in northern
300,000 years ago. Homo erectus was
gone from the scene by 250,000 BP, and 230,000 years
ago, the Neanderthals of northern
About 225,000 years ago, the Sangamon Interglacial age began, and
buried beneath a sheet of ice 2 miles thick.
200,000 years is the limit of our earliest K-Ar
dating, and ostrich eggshell amino acid
dating may also reach back that far. The Vostok
ice core from northern
By 160,000 BP, Middle Paleolithic mousterian and levalloisian flake tools were widely used.
130,000 year old Neanderthals of
Croatia sported an occipital bun. Modern human footprints
dated to 117,000 years ago have been found
on the west coast of
is the generally accepted time of the
appearance of modern Homo sapiens. A cave on the
southern coast of
between 95 and 80 thousand BP. By 90,000 BP,
modern humans lived in the
then, the Wisconsin Glacial age began.The
Neanderthals lived in
60,000 BP, and in
between 54-40,000 years ago suffered from CPPD
arthritis. Meteor Crater off I-40
in
The glaciers closest approach to this area is said to be the
49-41,000 BP we had a mild, moist
climate with deciduous forests and alligators (Alligator
mississippiensis), mastodons (Mammut
Between 40 and 38,000 BP, it was cooler
and drier with mainly pine and some oak forests,
and the mastodon, mammoth (Mammuthus
jeffersonii), ground sloth (Glossotherium harlani),
and large bison (Bison antiquus) roamed.
Reliable radiocarbon dating reach back
to 40,000 BP,
and this date was obtained from charcoal
and burned bone associated with human artifacts in
extinct black bear (Ursus americanus
amplidens), mammoths, two horse species (Equus
complicatus, and probably E. scotti), and bison
existed. The Late Wisconsin glacial stage ran
from 35,000-10,000 BP. Human evidence dated
back to 35,000 BP has been found in New
forests and muskox (Symbos cavifrons),
stilt-legged deer (Sangamona fugitiva), mastodons,
and ground sloths. The Neanderthal peoples
lived at
29,000 years ago, then they disappeared
from the earth.
A modern human Italian mother and fetus, from around 24,000 BP, has been
found
with a shell and ocher head covering and a
deer tooth necklace. Between 23-13,500 BP,
our climate was glacial, colder, and
drier, spruce forest predominated with some deciduous
willow, poplar, and elm, while ground sloths,
giant beaver (Castoroides ohioensis), tapir
(Tapirus veroensis), horse, and small
modern species browsed. Human materials in
been dated back to 20,000 BP and from this
time elsewhere the earliest ceramics, woven
textiles, and needles have been found. By
18,000 BP, the Laurentide ice sheet was at full
glacial interval, stretched well below the
continental exposure, including the land bridge
between
BP melted glacial ice had produced a
rise in sea levels of about 210 feet which flooded the
coastal areas of all continents. By 14,000 BP,
it was in late glacial interval with fingers
still reaching the bottom of the
a cold period called the Younger Dryas
stadial. A mastodon stuffed with wild gourd was
found in northern
butchered by humans near
pondweed, and swamp grasses. Evidence of human
activity has also been found on 11,300
year old mammoth remains just north of
Little is known of the early peoples of the western hemisphere but one
item is highly
revealing. This is their common use of the
been found throughout the western
hemisphere and are usually very well made. This
indicates a hunter driven society with a strong
sense of communication - possibly even
a common language throughout the north
and south
indicates constantly moving small family groups
and a reliance on poorly preservable
animal remains as tools. A
Jasper Co.,
Variabilities of weather and the
activities of living agents normally preclude that.
Recently observed variations in
atmospheric carbon-14 requiring adjustment to prior
radiocarbon dates exacerbates the problem.
Statistical analysis noting dates outside
the mean as unreliable would exclude the
above dates of human activity. A much greater
degree of certainty places the
types appear toward the end of this period,
and one each has been found in Ottawa Co. and
Jasper Co.
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REFERENCES
Asimov,
Chapman, C.H., 1975, The Archaeology of
Hunt, C.B., 1986, Surficial Deposits of the
National Geographic
O'Brien, M.J., 1996, Paradigms of the Past,
O'Brien, M.J., Wood, W.R., 1998, The Prehistory
of
Overstreet, R.M., 1997, The Overstreet Indian
Arrowheads Identification and
Price Guide.
Stearn, C.W., Carroll, R.L., Clark, T.H., 1979,
Geological Evolution of
John Wiley and Sons
Steyermark, J.A., 1959, Vegetational History of the
Missouri Studies, vol.31