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Fortunately for the history of the preliterate societies representing
the majority of the history of Homo sapiens, the essential difference
between humans and other animals is that humans possess culture which
permits them to manipulate their environments for their own well-being.
This manipulation involves tool making, dwelling construction, the
manufacture of clothing, and the endless array of 'artifacts' which
have permitted a semi-tropical species to occupy every environmental
zone on the planet. Humans are also universally concerned with their
origins and their ultimate place in the cosmos and, thus, in addition
to the secular artifacts and features there are structures and objects
which relate to cosmology, such as special cemeteries, temple mounds,
various stone cairn structures, and religious art and artifacts. Many
of these cultural manifestations survive the passage of time and
through the methods of the discipline of archaeology can be used to
reconstruct long vanished cultures.
Before proceeding, a review of the archaeological evidence prior to
12,000 years ago is in order. The evidence is limited, equivocal and,
therefore, controversial
(Dillehay and Meltzer 1991;
Dincauze 1984;
Meltzer 1989;
1993;
Morlan 1988;
1991). The nature of the pre-15,000
B.P. evidence from the Western Hemisphere stands in curious contrast
to the relatively clear evidence of early human settlement of Australia
and the initial occupation of northeastern Asia (Jelinek
1992). Relative to pre-20,000
B.P. evidence, either in eastern Beringia or in the Western Hemisphere
proper, there is also the problem that the earliest acceptable evidence
of people in northeastern Asia is 25,000 B.P. at the earliest and
pertains to cultures with an Upper Palaeolithic technology. It is a
fundamental premise that people out of Asia colonized the Western
Hemisphere. This premise is founded upon both biological and
anthropological evidence. Homo sapiens does not appear to have adapted
to the rigorous environmental conditions of northeastern Asia until
around 40,000 years ago
(Grayson 1988: 113;
Muller-Beck 1982). The earliest
generally accepted archaeological evidence from Western Beringia
(Eastern Siberia) pertains to the Diuktai culture, which is dated to
18,000 B.P.
(Aikens 1990;
Dikov 1978;
Morlan 1987;
Yi and Clark 1985). The Diuktai
culture assemblage is usually regarded as being ancestral to Northwestern
Palaeo-Arctic culture dated to 10,500 B.P. in Alaska although a
Palaeo-Indian culture ancestry has also been claimed
(Mochanov 1969). It should be
cautioned, however, that considerable regional and temporal variation
exists within "...a cultural horizon with wedge-shaped microcores and
bifacial points extended from the Yenisei to Hokkaido and from the
Huanghe Valley to the Northwest Territories of North America in terminal
Pleistocene times"
(Pei 1985: 14). There are a number
of problems with what would otherwise appear to be a neat lineal
progression of people and their cultures from Western Beringia to
Eastern Beringia and thence to the Western Hemisphere. First, the
Northwestern Palaeo-Arctic culture in Alaska has been recovered
stratigraphically above an earlier assemblage apparently lacking
microblade technology and dating to approximately 12,000 B.P.
(Powers and Hoffecker 1989).
Second, the evidence from the Bluefish Caves site in the northern Yukon
raises the possibility of a much earlier appearance in Beringia of the
microblade-burin technology typical of the Northwestern Palaeo-Arctic
culture (Morlan and Cinq-Mars 1989).
Third, the 12 dates on what appear to be human altered proboscidean
(mammoth and/or mastodon) bones from the Old Crow River in the Yukon,
range from 28,750 to 39,500 B.P. with an average of 33,382 B.P.
(Morlan et al. 1990: Table 3).
We are, therefore, faced with the paradox of having evidence of people in
Eastern Beringia as early as the earliest evidence from northeastern Asia
and a microlithic industry possibly dating as early as the earliest evidence
from Eastern Siberia. Certainly there are such gaps in the archaeological
records of both eastern Asia and adjacent North America that these
paradoxes should not be surprising.
As is the case with the archaeological evidence from Beringia, there is
controversy concerning the nature of the plant and animal communities.
One view is that a steppe-tundra, capable of supporting a large, diverse
mammal assemblage, existed
(Guthrie 1982); while the
contrary view interprets the evidence between 30,000 and 14,000 B.P.
to indicate a relatively impoverished, patchy herb tundra
(J. Ritchie 1984;
Ritchie and Cwynar 1982).
Unlike earlier, more favourable environments, this period was probably
characterized by polar desert conditions with dry, sunny summers, dry,
windy winters, and limited snow cover
(Schweger et al. 1982).
The incomplete plant cover would have consisted of a low vegetation
nearly devoid of trees. These patchy plant communities supported a
depleted version of the preceding period, namely mammoth, bison, horse,
caribou, mountain sheep, saiga antelope, and musk-ox. Between 14,000
and 13,000 B.P. sudden climatic change resulted in a rapid elevation
of sea levels and an increase in birch reflecting a wetter and warmer
climate which persisted for 5,000 years. It was during this period
that both the mammoth and the horse disappeared.
While a number of archaeologists would argue for a much earlier human
presence in the more southerly latitudes of the Western Hemisphere
(Bonnichsen and Young 1980;
Bryan 1969;
1978), it currently appears that
the immediate ancestors of the Palaeo-Indian people represent the
initial human migration to the south from the deteriorating environment
in Beringia. Two obvious questions are when and how? With reference to
the 'when', most archaeologists believe that the distinctive weapon tip
of Palaeo-Indian culture was invented south of the ice masses and only
subsequently penetrated north as far as Alaska. As Palaeo-Indian culture
has been dated to approximately 12,000 years ago, it logically follows
that their pre-fluted point ancestors must have existed for some time
south of the ice masses in order for the point style to be invented and
to diffuse north as environmental conditions ameliorated. Evidence of
pre-fluted point sites south of the glaciers, excluding equivocal claims
(Lynch 1990;
Morlan 1988), is quite limited.
If, however, as is speculated here, a small number of people managed
to work their way to the south shortly before 15,000 B.P. they could
have formed the nucleus of Palaeo-Indian culture and been the
innovators of the distinctive point style. Given the massive alterations
to Late Pleistocene landforms, detecting the archaeological evidence
of small, mobile groups of hunters across a dramatically altered
landscape can be understandably difficult. An alternative hypothesis
proposes that the fluted point was developed in Eastern Beringia, from
where it was carried through the corridor between the Continental Ice
Sheet and the Cordilleran Ice of the Rocky Mountains to be widely
adopted by already resident populations
(Morlan and Cinq-Mars 1982:
380-381). There is currently no evidence of early fluted projectile points
in Eastern Beringia except from the controversial Putu site
(Alexander 1987) which has
probably been too readily dismissed.
In addition to the issue of when the first people penetrated the Western
Hemisphere there is also the question of how. Given the glacial
conditions and environments of the Late Pleistocene period there are
only two plausible routes: through an ice-free corridor along the
eastern flank of the Rocky Mountains, or by water transport following a
chain of refugia along the west coast. With reference to both routes
northern hunters, with their intimate knowledge of animal behaviour
including bird and other animal migratory habits, would have known land
existed to the south although not necessarily how far.
The ice-free corridor route is the older of the two hypotheses and is
still generally the most favoured. Despite intensive and focused research
(Ives et al. 1989), however,
this route has still not been demonstrated to be that followed by the
earliest hunting bands into the heart of the continent. The earliest
archaeological evidence in the corridor dates to 10,500 B.P. and more
likely represents a late northward thrust long after the initial
occupation of the Western Hemisphere. In the portion of the corridor
from the Athabasca River Valley to Montana a cold, dry tundra prevailed
between 24,000 and 11,400 B.P. with birch and poplar/aspen appearing at
the end of the period
(Schweger 1989: 498). As early
as 14,000 B.P. environmental conditions in the corridor had ameliorated
somewhat and would have been more favourable for migrants than the
preceding 6,000 years
(Ives et al. 1989). There is
also evidence that the Laurentide and Cordilleran ice sheets did not
coalesce until 15,000 B.P., if then, suggesting the existence of a
corridor into the interior of the continent from the north between
45,000 and at least 15,000 B.P.
(Bobrowsky and Rutter 1990).
The main point to make relative to the corridor is that throughout
much of the period it was believed to be open it constituted 2,000 km
of hostile, barren country. A secondary consideration, but one of vital
importance to archaeology, is the probability that any human movement
through the corridor was likely to have been quite rapid, leaving little
archaeological trace. On the other hand, if Late Pleistocene caribou herd
behaviour was similar to that of today then the elevated, dry, harsh
climate of the corridor would have been ideal as seasonal calving grounds
and could have led to both the northern and southern portions of the
corridor attracting large herds during the warmer months of the year.
Such a hypothesized rich seasonal animal resource could have resulted
in substantial sites. Geological evidence suggests that the high terraces
of the corridor were likely uninhabitable in contrast to the alluvial fans
(Levson 1990). But if the caribou
calving grounds hypothesis has any validity it will be necessary to
reconstruct Late Pleistocene land forms in the corridor in order to
predict where early archaeological sites would most likely be
encountered.
A west coast migration route used by sea-faring people who exploited
coastal refugia was first suggested by Knut R. Fladmark
(1979) and, while feasible
between 15,000 and 10,500 B.P.
(Luternauer et al. 1989),
like the corridor hypothesis, lacks concrete evidence. Indirectly
supporting the hypothesis is the present linguistic diversity of
the West Coast which contrasts with the much simpler linguistic
situation to east of the Continental Divide. This linguistic
diversity has been explained as a product of early peoples occupying
the refugia
(Rogers et al. 1990) although
there are a number of major theoretical problems with the proposition.
A fundamental assumption of the coastal route hypothesis is that the
migrating people were proficient maritimers in possession of
sophisticated watercraft. While evidence of watercraft rarely survive
in the archaeological record, the foregoing assumption is, in all
probability, correct even if the coastal hypothesis is not. In northern
latitudes, in particular, the rich maritime animal resources must have
been a strong attraction for any hunting peoples. Certainly it is
inconceivable that Palaeo-Indian culture people could have functioned
in the rapidly changing Late Pleistocene environments without some form
of watercraft and, indeed, settlement pattern evidence indicates islands
were often exploited
(Storck 1979). The single
greatest weakness with the coastal hypothesis is that it is difficult
to test due to post-glacial submergence of the coastal refugia.
Similarly, any east coast Late Pleistocene archaeological evidence is
'out to sea'
(Porter 1988: Figure 5). In
regions such as the Vancouver area, where sea levels between 10,000
and 11,000 B.P. approximated today's levels, there is no evidence of
Palaeo-Indian culture
(Roberts 1984: 15). There is
also the problem of how maritime adapted people could get south of
the frozen Alaska Peninsula much less survive on the hostile refugia
(Reanier 1990). The limited
evidence for Palaeo-Indian culture in the Pacific Northwest and its
lateness (Meltzer and Dunnell 1987)
suggests that the ancestors of these people did not arrive in the
region as accomplished maritimers. The fact that the earliest
recognized colonists survived in the rapidly changing environments
of the glacial-interglacial transition is proof enough that they were
superb generalists and opportunists capable of rapid adaptive cultural
adjustments. As such, these earliest people could have possessed both
maritime and interior adaptive strategies and, thus, been able to
accommodate either or both interior and coastal migration routes.
At this point, however, neither of the two routes into the Western
Hemisphere has been demonstrated. What can be demonstrated is that
around 12,000 years ago people were widespread in the interior of
the continent. It must be cautioned that the 'burst' of Palaeo-Indian
culture upon the scene 12,000 years ago may be more apparent than real.
The archaeological visibility of Palaeo-Indian culture is very much
keyed to the distinctive lanceheads which, in various forms, were used
for approximately 1,000 years. Indeed, the majority of Palaeo-Indian
sites have been dated by these projectile point 'index fossils' rather
than by datable samples recovered from good archaeological contexts.
Theoretically earlier sites lacking such a convenient 'index fossil'
cannot be typologically dated and thus cannot be given a cultural
assignment. The major Palaeo-Indian sites tend to be kill sites in the
west, where large animals were killed and butchered, or seasonal
residential sites in the east, often associated with stone quarries and
lacking bone preservation. In addition to the limitations in the
archaeological record there are the considerable difficulties in
attempting to comprehend the unique event of the human occupation of an
entire hemisphere with its great diversity of physiography and
environments. The occupation and exploration of the Western Hemisphere
by Palaeo-Indian culture and its derivatives must be accorded respect
as one of the greatest accomplishments in the history of our species.
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