Younger Dryas environments and human adaptations

Transcription

Quaternary International 242 (2011) 463e478
Contents lists available at ScienceDirect
Quaternary International
journal homepage: www.elsevier.com/locate/quaint
Younger Dryas environments and human adaptations on the West Coast of the
United States and Baja California
Leslie A. Reeder a, *, Jon M. Erlandson b, Torben C. Rick c
a
Department of Anthropology, Southern Methodist University, Dallas, TX 75275-0336, USA
Museum of Natural and Cultural History and Department of Anthropology, University of Oregon, Eugene, OR 97403-1224, USA
c
Program in Human Ecology and Archaeobiology, Department of Anthropology, National Museum of Natural History, Smithsonian Institution, Washington D.C. 20013-7012, USA
b
a r t i c l e i n f o
a b s t r a c t
Article history:
Available online 22 April 2011
On the Pacific Coast of the United States and Baja California, the Younger Dryas was one component of
dynamic Late Pleistocene and Holocene environmental changes. Changing climate, sea level rise, and
shifting shorelines created ecological challenges for ancient coastal peoples and daunting challenges for
archaeologists searching for early coastal sites. This paper reviews the evidence for ecological change in
this ‘West Coast’ region, including shoreline changes that may have submerged or destroyed archaeological sites from this time period. Examining the regional record of human occupation dating to the
Younger Dryas, well-dated coastal sites are limited to California’s Northern Channel Islands and Isla
Cedros off Baja California. A small number of fluted points found in coastal areas may also date to the
Younger Dryas, but their context and chronology is not well defined. Review of the implications of these
two data sets considers whether the early but discontinuous Younger Dryas archaeological record from
the West Coast might result from a migration of maritime peoples from Northeast Asia into the Americas.
Ó 2011 Elsevier Ltd and INQUA. All rights reserved.
1. Introduction
Along the coasts of Washington, Oregon, California, and Baja
California (hereafter referred to as “the West Coast”), the Younger
Dryas was one of several periods of dramatic environmental
changes during the transition from the Last Glacial Maximum
(LGM) to the Holocene. Extensive paleoecological research along
the West Coast provides a strong foundation for examining
human responses to the Younger Dryas, as both marine and
terrestrial deposits supply detailed records of environmental
changes. The Younger Dryas affected both terrestrial and marine
climate, but the extent of its impact on regional flora and fauna is
less evident. This is a region of relatively mild climate, rich
resources, and spectacular variabilitydranging from temperate
rainforests in the north to Mediterranean semi-arid scrub and
chaparral in the south. Elevations reach over 3000 m within
several kilometers of the coast and shorelines boast some of the
most productive nearshore marine ecosystems in the world
(Fig. 1). Amid this variability, significant questions remain about
the relationship between Younger Dryas climate change and
human adaptations and life ways.
* Corresponding author. Fax: þ1 214 768 2906.
E-mail address: [email protected] (L.A. Reeder).
1040-6182/$ e see front matter Ó 2011 Elsevier Ltd and INQUA. All rights reserved.
doi:10.1016/j.quaint.2011.04.016
This paper reviews the environmental conditions of West Coast
marine and terrestrial ecosystems, focusing on those records
directly applicable to the coast but including interior records that
inform on broader climate patterns. It also synthesizes and evaluates the archaeological record of Younger Dryas and earliest
Holocene occupations, including divergent evidence provided by
faunal remains and early lithic traditions. There is ample reason to
believe that numerous early West Coast archaeological sites have
been lost to rising post-glacial seas and coastal erosion (Moss and
Erlandson, 1995; Erlandson et al., 1998, 2008). While these problems seriously impair the understanding of the earliest human
occupations in the area, several terminal Pleistocene sites have
been identified in the region during the last decade. These early
coastal sites come from two restricted areas, however, and the
possibility should be considered that the sparse Younger Dryas
archaeological record along the West Coast results from relatively
small coastal populations concentrated primarily in the richest
coastal habitats.
2. Environmental impact of the Younger Dryas
The West Coast contains a wide range of environments, from the
temperate rainforests of the Northwest Coast to the desert coasts of
Baja California (Erlandson et al., 2008). The southern Northwest
Coast, from the Canadian border to Cape Mendocino in northern
464
L.A. Reeder et al. / Quaternary International 242 (2011) 463e478
Fig. 1. Overview of the West Coast, including major regions and specific locations discussed in the text.
California, is a region of high rainfall and moderate temperatures
where dense forests and acidic soils have hampered archaeological
preservation and research. The cool, wet winters and long, dry
summers of central and southern California’s semi-arid Mediterranean climate support a more open vegetation consisting of
chaparral and scrub, oak woodland, and sparse conifer forests.
Although still essentially Mediterranean, conditions are even more
arid in Baja California, with increasingly xeric vegetation and
harsher conditions. However, these three regions are connected by
rich and diverse marine ecosystems, supported by the cold California Current, coastal upwelling, and rich kelp forests and
estuaries.
The transition from LGM to Holocene climates was not smooth
on the West Coast, and ecological responses to shifting
precipitation and temperature regimes were variable. During the
LGM, climate models suggest that massive North American Ice
Sheets shifted the polar jet stream southward, bringing greater
moisture to the southern part of the West Coast and depriving the
southern Northwest Coast of its high interglacial precipitation
(Bartlein et al., 1998; Feng et al., 2007). These models also suggest
that an anti-cyclone atmospheric pattern above the Laurentide Ice
Sheet brought drier continental air to the Northwest Coast, and
a relatively intense Aleutian low-pressure system in winter would
also have shifted precipitation to the south. This pattern had
weakened by the beginning of the Younger Dryas as Ice Sheets
retreated, eastern Pacific high-pressure systems strengthened, and
atmospheric circulation approached modern conditions (Bartlein
et al., 1998).
Lowered sea levels exposed broad swaths of now-submerged
coastal plain habitats in some areas, while others remained
mountainous and steep. At the LGM, sea levels reached as much as
140 m below modern mean sea level (MSL), then rose rapidly
through the rest of the Pleistocene and early Holocene. At the
beginning of the Younger Dryas (w13,000 BP; all dates provided are
in calibrated years before present, unless otherwise noted), sea
levels were roughly 75 m below modern MSL. Records differ during
the later part of the Younger Dryas, but sea level rise seems to have
stabilized, followed by a rise to around 60 m below modern MSL at
11,000 BP (Lambeck et al., 2002; Masters and Aiello, 2007). By
9000 BP, sea levels were w30 m lower than today, although records
from southern California suggest that there may have been a faster
Early Holocene rise in this region (Inman, 1983; Masters and Aiello,
2007). In fact, estimates of sea level rise during the late Pleistocene
and early Holocene vary by up to 30 m (Inman, 1983; Bard et al.,
1990, 1996; Hanebuth et al., 2000), but composite reconstructions
for both global (Lambeck et al., 2002) and regional (Masters and
Aiello, 2007; Kennett et al., 2008) sea level rise support the
values used here.
Shoreline reconstructions for the beginning and end of the
Younger Dryas (Fig. 2) were produced by estimating the location of
ancient sea levels on modern topography and are comparable to
465
other regional reconstructions provided by Masters and Aiello
(2007) and Kennett et al. (2008). Ten millennia of erosion, sedimentation, tectonic movement, and isostatic adjustments significantly altered the topography in some areas, but these are
reasonable estimates of the location of ancient shorelines. Digital
elevation models (DEMs) produced by the NOAA NGDC Marine
Geology and Geophysics Division were used for much of the coast.
Where these were not available, bathymetric data were collected
from the California Department of Fish and Game and topographic
data from NOAA’s ETOPO1 Global Relief Model (Amante and Eakins,
2009).
2.1. Glaciers
Except on the Olympic Peninsula, coastal mountains of the West
Coast are generally too low to support glaciers, with only isolated
peaks reaching over 1250 m above MSL. The Puget lowlands
were still heavily glaciated by Cordilleran Ice Sheets until about
16,000 years ago (the Vashon Stade), however, and the Olympic
Mountains of northwestern Washington still support some 266
alpine glaciers today (Porter and Swanson, 1998; Thackray, 2001;
Booth et al., 2004). Throughout the Pleistocene, glaciers in these
maritime mountains remained independent of the Cordilleran Ice
Sheet and contrasted with their more continental neighbors by
tending to grow more during periods of high moisture than during
periods of low temperature. During the LGM, lack of moisture due
to the Laurentide anti-cyclone and the shifted polar jet stream
constrained the growth of the Olympic glaciers (Thackray, 2008).
As a result, the LGM (Twin Creeks I) valley glaciers advanced only
to the easternmost coastal plain. A second, smaller (Twin Creeks II)
advance post-dates the first, but cannot be constrained to the
Younger Dryas (Thackray, 2001). This is similar to the pattern seen
elsewhere in Cordilleran and alpine glaciers of southwest Canada,
where post-LGM advances occurred in response to changes in
climate circulation patterns, air and sea surface temperatures, and
precipitation that only sometimes correspond with the Younger
Dryas (Menounos et al., 2009). A later advance of the Cordilleran
Ice Sheet into the Puget Lowlands (the Sumas Stade) likely corresponds with the Younger Dryas, but it moved only into northernmost Washington and remained just a few hundred years (Booth
et al., 2004).
2.2. Terrestrial environments: the southern Northwest Coast
Fig. 2. Approximate shoreline positions during the Younger Dryas. Closer images of
the Santa Barbara Channel and the west coast of Baja California can be seen in Figs. 4
and 5, but the inset in this map shows the relatively dramatic shoreline movement
associated with the late Pleistocene in Washington and northern Oregon.
Late Pleistocene vegetation changes along the West Coast were
complexdplant taxa changed latitude, altitude, and association
rapidly in response to alterations in temperature, precipitation, and
shorelines. Pollen cores provide some of the best records of ancient
terrestrial environments along the West Coast, but many suffer
from problems of chronology (limited numbers of 14C dates and
large age ranges) and resolution that make it difficult to understand
the dynamics of sub-millennial scale climate change. Resolution of
lacustrine pollen is sometimes good enough to track the Younger
Dryas event (or lack thereof), but rarely good enough to see the
details of the transition into and out of the Younger Dryas (Table 1).
As with glacial evidence, many pollen cores reflect changes in
climate out of synch with the onset of the Younger Dryas, suggesting complex regional interaction with global climate trends.
On the Northwest Coast, the general trend of the late glacial
period was a movement from tundra to boreal forest to temperate
forest, with gradients primarily along altitudinal and latitudinal
lines. Because lakes are common in the Pacific Northwest, there
are many studies of climate change through pollen frequencies
(Table 1), although many of these are located in the interior. Pollen
samples commonly show increased parkland and tundra between
466
Table 1
Important sources of pollen and other terrestrial climate data relevant to the Younger Dryas. Numbers in the second column correspond to locations in Fig. 3, while the
parenthetical numbers in the fourth column refer to the number of dates within the 15,000e10,000 cal BP range. These give a sense of the accuracy and resolution of the data
sets from each site.
Site name
Map
symbol
Elev./
Depth (m)
Age range (No. dates
from 15e10 ka BP)
Climate change proxy
YD environment
Sources
Arlington Canyon
47
104
13,500 BP to Present
Lithology, %Corg, charcoal
concentration, pollen
Pollen
Pollen and charcoal
Yes
Kennett et al., 2008
Barrett Lake
Battle Ground Lake
36
15
2816
155
15,000 BP to Present (1)
No (Poor chronology)
Maybe
Weak
Anderson, 1990
Barnosky, 1985b;
Walsh et al., 2008
Mohr et al., 2000
Bluff Lake
26
1921
Bogachiel Drainage
Bolan Lake
5
24
179
1638
>30,000 BP to Present (1)
Carp Lake
14
714
Castor Lake
Clear Lake
3
28
Coast Trail Pond
Daisy Cave
Davis Lake
F2-92-P03 (marine)
Maybe
Maybe
Heusser, 1983
Briles et al., 2005
Pollen, charcoal;
Deposition rates; Magnetic
susceptibility; Sediment
organic content
Pollen
Pollen, plant macrofossils,
charcoal
Pollen
No (Low resolution)
591
404
14,000 to 11,000 BP (2)
Sedimentary geochemistry
Pollen
Yes
No
31
46
13
41
7
10
342
803
n/a
11,600e8500 BP (16)
Pollen
Pollen
Pollen
Pollen
Maybe
No (Low resolution)
No
Yes
F2-92-P29 (marine)
50
1475
Pollen
Weak
Gordon Lake
Hoh Drainage
Humptulips Mire
17
6
9
1177
179
56
Offset
Maybe
Offset
Indian Prairie
Kirk Lake
16
n/a
1127
190
Lake Carpenter
Lake Washington
Little Lake
7
10
18
9
50
217
Mineral Lake
Mumbo Lake
12
27
435
1875
Nichols Meadow
38
1509
Nisqually Lake
11
71
Pollen
Pollen
Pollen and plant
macrofossils
Pollen
charcoal
Pollen; Diatoms
Pollen
Pollen; Magnetic
susceptibility; sedimentary
geochemistry
Pollen
charcoal
charcoal
Pollen
Barnosky, 1985a;
Whitlock and Bartlein, 1997;
Whitlock et al., 2000
Thornburg, 2006
West, 2001;
Adam and Robinson, 1988;
Adam and West, 1983;
Adam et al., 1981
Rypins et al., 1989
Erlandson et al., 1996
Barnosky, 1981, 1985a
Gardner et al., 1997;
Heusser, 1998
Heusser, 1998
Grigg and Whitlock, 1998
Heusser, 1977, 1983, 1985
Heusser et al., 1999;
Heusser, 1960
Sea and Whitlock, 1995
Cwynar, 1987
ODP-893 (marine)
44
576
Pollen, charcoal
ODP-1019 (marine)
Oregon Caves Nat’l Mon.
Quinault Drainage
Sculptured Beach
Secret Beach
Soledad Pond
Starkweather Pond
Swamp Lake
25
23
8
33
32
48
35
34
980
1100
32
41
37
275
2438
1554
13,300
15,000
14,000
14,000
12,000
14,000
17,500
V1-80-P03 (marine)
29
1430
Pollen
Speleothem geochemistry
Pollen
Pollen
Pollen
Pollen, charcoal
Pollen
charcoal
Pollen
Yes (charcoal),
Offset (pine pollen)
Yes.
Yes/weak
No (Low resolution)
Maybe
Maybe
No (Low resolution)
No
No
W8709A-13 (marine)
22
2712
Pollen
Weak
W8709A-08 (marine)
Y71-10-117P (marine)
Y7211-1 (marine)
20
45
19
3111
576
2913
Pollen
Pollen
Pollen
Yes
No
Weak
17,500 to 7000 BP (2)
>16,500 BP to Present (1)
BP to
RYBP
BP to
BP to
BP to
BP to
BP to
Present (8)
to Present (3)
Present (5)
Present (2)
Present (1)
Present (1)
Present (1)
about 28,000 and 14,000 BP (Grigg and Whitlock, 2002) corresponding to dryer, colder atmospheric conditions, after which
closed boreal forests of pine and spruce developed (Heusser, 1985;
Jimenez-Moreno et al., 2010). Pollen sites can be broadly divided
Maybe
No
No
No
Offset
No
No
Anundson et al., 1994
Leopold et al., 1982
Grigg et al., 2001;
Worona and Whitlock, 1995;
Grigg and Whitlock, 1998
Heusser, 1983
Daniels et al., 2005
No
Koehler and Anderson, 1994
No (Poor chronology)
Heusser, 1983;
Barnosky 1985a
Heusser and Sirocko, 1997
Yes
Barron et al., 2003
Vacco et al., 2005
Heusser, 1983
Rypins et al., 1989
Rypins et al., 1989
Anderson et al., 2010
Anderson, 1990
Smith and Anderson, 1992
Heusser, 1998
Ortiz et al., 1997;
Heusser, 1998
Heusser, 1998; Mix et al., 1999
Heusser, 1978
Heusser, 1998
into four geographic categoriesdcoastal sites (Bogachiel, Quinalt,
and Hoh drainage systems, Humptulips Mire, and Little Lake),
interior lowland sites (Lake Carpenter, Lake Washington, Nisqually Lake, and Battle Ground Lake), interior upland sites (Carp,
Castor, Gordon, Mineral, and Davis lakes), and the Klamath
uplands (Oregon Caves, Bolan Lake, Indian Prairie, Bluff Lake, and
Mumbo Lake).
For the purposes of this study, the coastal sites are the most
interesting but also have generally the poorest chronology and
resolution. At Humptulips Mire, a short increase in pine might
suggest a return to cooler and drier climates, but vegetation
changes do not coincide with Younger Dryas climate change
(Heusser et al., 1999). The Quinalt section also does not reflect
a Younger Dryas climate change (Heusser, 1983), and the sections at
Bogachiel and Hoh rivers show small but ambiguous changes
around the time of the Younger Dryas with problematic chronological control (Heusser, 1983, 1985). Little Lake is at a higher
elevation and further south than other coastal sites, located on the
west slope of the Oregon coastal ranges, but shows a pattern similar
to that at Humptulips, with a spike in pine pollen that does not
coincide with the Younger Dryas (Worona and Whitlock, 1995;
Grigg and Whitlock, 1998; Grigg et al., 2001).
Sites within the Puget lowlands are more heavily influenced by
recent deglaciation and marine incursions caused by isostatic and
eustatic adjustments, and Younger Dryas climate change does not
register (Leopold et al., 1982; Heusser, 1983; Anundson et al., 1994).
Further to the south, however, two sites in the Willamette lowlands
(Battle Ground and Little lakes) that were further from the influence of the Cordilleran Ice Sheet display reversals in vegetation
change, but these do not coincide with the Younger Dryas
(Barnosky, 1985b; Walsh et al., 2008). In general, lowland sites see
temperate species such as alder and fir expand (Barnosky, 1985a),
alongside an increase in fire frequency that Walsh et al. (2008)
attributed to the increased fuel provided by the closing canopy.
Upland sites in both the Cascade and Klamath Ranges are
similarly ambiguous in their responses to the Younger Dryasdsome show no evidence for vegetation changes, but continue
on trajectories towards warmer, wetter vegetation regimes (i.e.
Mineral, Davis, Carp, and Mumbo lakes) while others display small
changes corresponding to the Younger Dryas (i.e. Indian Prairie,
Bolan Lake, and Bluff Lake) and still others have reversals to more
cold-weather vegetation that occur too early (i.e. Gordon Lake)
(Barnosky, 1981, 1985a; Sea and Whitlock, 1995; Grigg and
Whitlock, 1998; Mohr et al., 2000; Whitlock et al., 2000; Briles
et al., 2005; Daniels et al., 2005). Overall, upland pollen cores
suggest a gradual transition from an open spruce/mountain
hemlock forest coincident with the Vashon stade to a mixed
woodland of subalpine and lowland conifers, with minimal reversal
indicative of the Younger Dryas or the Sumas stade.
Interestingly, two sites that show the strongest evidence for
Younger Dryas climate change are not based on pollen cores,
possibly suggesting that some portions of the ecosystem reacted
more quickly and more strongly to the Younger Dryas than others.
At Castor Lake, the most northerly and interior terrestrial site, lake
levels drop and terrestrial and aquatic productivity decrease near
the beginning of the Younger Dryas (Thornburg, 2006). A speleothem record from Oregon Caves National Monument also shows
a distinct and well-dated temperature decrease based on v18O
values, but v13C values (reflecting elevated biomass or precipitation) increased more or less steadily between 13,300 BP and the
Holocene, with only limited evidence for the Younger Dryas (Vacco
et al., 2005).
Pollen from ocean cores also provides information about
regional climate change, often at a higher temporal resolution and
with better chronological control than the more local lake records
(Table 1). Three cores off the Oregon Coast (W8709A-13, W8709A08, and Y7211-1) record a shift from an open, pine-dominated
woodland to more complex closed Holocene forests. Peaks in
alder pollen record wet periods, one of which occurs near the onset
467
of the Younger Dryas and the other about 2000 years earlier
(Heusser, 1998). In general, pollen fluctuations in these cores reflect
an unstable and changing environment throughout the transition
from LGM to Holocene, but changes can rarely be independently
and directly correlated with the Younger Dryas. Pollen from core
ODP-1019 suggests overall warmer and wetter conditions during
the Bølling-Allerød but also documents considerable fluctuations
within the period. An increase in pine pollen marks the beginning
of the Younger Dryas, but the cool, wet conditions that this implies
are not sustained (Barron et al., 2003).
2.3. Terrestrial environments: Alta and Baja California
For the same reasons that the Northwest Coast was cooler and
drier during the LGM than today, the California Coast was cooler
and wetter (Stott et al., 2002). Basic vegetation assemblages were
very similar to those seen today, however, except for the southward
range extension of some mesic species (Minnich, 2007). In a recent
review, West et al. (2007) suggest that, although the Younger Dryas
registers in many pollen cores, vegetation changes appear to have
been relatively minor. Data on late glacial environments come from
lakes and meadows in the Sierra Nevada, Clear Lake in central
California, the Point Reyes Peninsula on the central coast, and a few
locations in southern and Baja California.
Records from the west slope of the Sierra Nevada, although not
directly applicable to coastal environments, demonstrate
a continued pattern of limited Younger Dryas impacts on inland and
upland areas. At high-altitudes, landscapes were only recently
deglaciated, with few trees and tundra-like, herbaceous pollen
(Anderson, 1990). At lower-altitude sites such as Swamp Lake in
Yosemite National Park and Nichols Meadow, pollen that accumulated throughout the Younger Dryas cannot be distinguished from
the period before or from the early Holocene (Smith and Anderson,
1992; Koehler and Anderson, 1994). At Clear Lake, on the eastern
slope of the Coast Ranges, West (2001) suggested that a brief
reversal in the trend of decreasing pine pollen and increasing oak
pollen through time might represent the Younger Dryas cooling. An
old-carbon effect makes chronological control difficult, however,
and researchers ultimately must correlate their pollen changes
with externally identified climate change (Adam and Robinson,
1988; West, 2001).
The best evidence for late Pleistocene and early Holocene
vegetation change along the central California Coast comes from
three sections on Point Reyes Peninsula (Fig. 3). These coastal
sections have good chronological control, but there is little
evidence of a Younger Dryas reversal. Instead, a closed forest of fir
and Douglas fir persists through much of the latest Pleistocene and
earliest Holocene. The only notable event is a period of rapid
sedimentation, dated a millennium or so before the Younger Dryas,
which is interpreted as evidence for higher storm activity (Rypins
et al., 1989).
Off the coasts of northern and central California, respectively,
ocean cores V1-80-P3 and F2-92-P03 show similar fluctuations to
those off the Oregon Coast, supporting the idea that regional
vegetation during the latest Pleistocene was highly dynamic.
Changes among some species suggest a Younger Dryas shift to
a cooler, drier interval, but many species continue their post-LGM
trends that would correspond with increasing warmth and moisture. Responses to the Younger Dryas may have varied even among
species living within the same ecosystems (Heusser, 1998).
In two southern California ocean coresdY71-10-117P and F292-P29dthe transition from the LGM to the Holocene is marked by
an overall shift from conifer forests to oak woodland/chaparral/
scrub communities, interrupted by brief wet periods (Heusser,
1998). Also off the southern California Coast, Core ODP-893,
468
Fig. 3. Sites with paleoenvironmental data relevant to the Younger Dryas on the West Coast. Numbers correspond to localities described in Tables 1 and 2.
located within the relatively enclosed Santa Barbara Basin, has
exceptional chronological control and has been much more thoroughly studied for pollen and other terrestrial indicators (Heusser
and Sirocko, 1997; Heusser, 1998). Heusser and Sirocko (1997)
identify a period of “enhanced seasonality” characterized by
strong winter monsoons and hot, dry summers near the beginning
of the Younger Dryas, although several others occur between about
15,800 and 8800 BP. A spike in charcoal accumulation also occurs at
around 13,000 BP (Kennett et al., 2008).
On the Northern Channel Islands, several sites provide pollen,
macrobotanical, and sediment data for the late glacial period,
including Daisy Cave, Soledad Pond, Arlington Canyon, and
Canada de los Sauces. At Daisy Cave and Canada de los Sauces,
evidence points to the presence of extensive conifer forests on
islands that have only sparse trees today (Erlandson et al., 1996;
Anderson et al., 2010). Fossil trees and cones from scattered
locations on Santa Cruz, Santa Rosa, and San Miguel islands (e.g.
Orr, 1968; Johnson, 1972) support the pollen data. By the Younger
Dryas, coniferous forests had declined significantly on the islands
and some conifer species had disappeared entirely. At Soledad
Pond, the record does not begin until about halfway through the
Younger Dryas, but minimal pine pollen is present by 11,800 BP,
and drier, near-modern vegetation was established by w11,000 BP
(Anderson et al., 2010). In Arlington Canyon, unusual amounts of
charcoal are followed by 4 m of sediment with less charcoal, all
dated between about 13,100 and 12,800 BP. Kennett et al. (2008)
interpreted this sequence as a period of landscape burning followed by mass erosion into the canyon, possibly linked to the
controversial Younger Dryas Cosmic Impact hypothesis (see
Firestone et al., 2007).
Paleoenvironmental records from Baja California are rare due to
the scarcity of environments favorable to pollen preservation. A
packrat midden in the Sierra San Francisco from the Younger Dryas
(12,820e11,310 BP) contains vegetation similar to modern Alta
California chaparral (Rhode, 2002), indicating a cooler, wetter and
more seasonal climate. Ocean cores in the Gulf of California, which
contain pollen from the Sonoran Desert, cannot be used to
supplement the minimal record of terrestrial climate change in Baja
California.
In sum, the Younger Dryas influenced terrestrial environments
on the West Coast, but responses were variable, seemingly not very
dramatic, and reconstructions are hindered by chronological
469
Table 2
Ocean cores with data relevant to Younger Dryas climate change. Numbers in the second column correspond to locations in Fig. 3.
Site
Map #
EW9504-13
40
Depth (m) Climate change proxy
2510
EW9504-17
21
2671
F2-92-P03
41
803
F2-92-P34
42
610
F8-90-G21
39
1605
F8-90-G25
37
1720
GC31/PC08
58
700 m
GC32/PC10
JPC-48
JPC-56
56
51
55
430
530
818
JT96-09PC
2
920
L13-81-G138 30
2531
Evidence for Younger Dryas
606
MD02-2512
52
477
MD02-2515
54
881
NH15P
south
of map
420
NH22P
2025
ODP-0480
south
of map
south
of map
53
ODP-0893
44
577
ODP-1017
43
955
ODP-1019
25
989
TT39-PC12
1
2369
(biogenic silica, CaCO3,
v18O); Faunal assemblages;
Sediment structure;
Faunal assemblages and
flux rates; Faunal stable
isotopes (v18O and d13C);
Sediment structure and
color; Magnetic susceptibility
(alkenone, CaCO3, Corg, v15N),
Major and trace elements,
Faunal assemblage;
Faunal isotopes (v13C)
Faunal assemblages;
Faunal stable isotopes (v18O);
(Corg, CaCO3, v18O, alkenone)
Faunal assemblages
TT39-PC17
4
2795
Faunal assemblages
V1-80-P03
29
1600
Faunal assemblages
V1-81-G15
49
1000
Faunal assemblages
655
Radiolaria suggest lower SST, v O
suggest no change
Decreased upwelling, but no SST
change evident
Sabin and Pisias, 1996;
Gardner et al., 1997
Decreased upwelling
Gardner et al., 1997
No. Consistent post-LGM
warming trend peaks around 10,500 BP
Faunal assemblages
No. Consistent post-LGM
warming trend peaks around 10,500 BP
Sedimentary geochemistry (Corg); Weak. Laminated sediments appear after, but not
Trace elements;
before, YD. Minimal change in productivity.
Sediment structure
Sedimentary structure
No. No change in sedimentary structure
Sedimentary structure
Yes. Massive sediments correspond with YD
Yes, YD is transitional. Warm-water incursions are
more frequent. Upwelling and productivity both
(biogenic opal, CaCo3, v18O,
v13C); sedimentary structure
somewhat low. Massive sediments correspond
with YD.
Yes. Reduced YD SSTs
(alkenone)
Faunal assemblages
Maybe. Post-LGM period highly variable–a small dip
in SST around 12,500 BP may represent the YD.
Weak. Slightly higher terrigenous sediment input.
Magnetic susceptibility;
(Corg, CaCO3); Trace elements
Weak. Massive sediments correspond with YD. Very
Sediment structure;
small reduction in productivity.
(v18O); Trace elements;
Diffuse spectral reflectance
Sediment structure;
Yes. Lower productivity
18
(v O); Trace elements;
Diffuse spectral reflectance
Weak. Small reduction in productivity. Laminated
Sediment structure;
sediments continue throughout the YD.
(Corg); Trace element
15
Sedimentary geochemistry (d N) Weak. Small reduction in upwelling and productivity
58
1018
Pisias et al., 2001
18
MD02-2508
NH8P
Sources
No apparent change in SST
Faunal assemblages;
Faunal stable isotopes (v18O)
Faunal assemblages;
(CaCO3, Corg, biogenic
opal); Faunal assemblages
(CaCO3, Corg, biogenic opal)
Faunal assemblages
15
Sedimentary geochemistry (d N) Weak. Small reduction in upwelling and productivity
Pisias et al., 2001
Sabin and Pisias, 1996
Dean et al., 2006;
van Geen et al., 2003;
Ortiz et al., 2004
Van Geen et al., 2003
Cheshire et al., 2005
Cheshire et al., 2005;
Pride et al., 1999; Sancetta, 1995;
Keigwin, 2002
Kienast and McKay, 2001
Blanchet et al., 2007
Dean et al., 2006
Ganeshram et al., 1995
Ganeshram et al., 1995
Yes. Massive sediments correspond with YD. Reduced Barron et al., 2004;
winter upwelling and more frequent warm-water
Keigwin and Jones, 1990
incursions.
Yes. Most studies point to a marked response
of SST and productivity to the beginning of the YD,
although transition into EH is varied and gradual.
Massive sediments restricted to the YD.
Kennett and Ingram, 1995;
Hendy et al., 2002;
Kennett et al., 2008;
Nederbragt et al., 2008
Yes. SST and productivity are lower.
Hendy et al., 2004; Seki et al., 2002
Yes. SST lower, but estimates vary widely.
Reduced upwelling and productivity.
Mix et al., 1999; Barron et al., 2003;
Pisias et al., 2001
No. Slightly warm SST from 13,000e9000 BP,
peaking around 12,000 BP.
No. Persistent post-LGM warming,
but sampling ends around 12,000 BP.
Maybe. Post-LGM period highly variableda small dip
in SST around 12,500 BP may represent the YD.
No. Consistent post-LGM warming trend
peaks around 12,000 BP
(continued on next page)
470
Table 2 (continued )
Site
Map #
W8709A-08
20
Depth (m) Climate change proxy
3111
Faunal assemblages;
W8709A-13
22
2712
Faunal assemblages;
Faunal stable isotopes (v13C,
and v18O); Sedimentary
geochemistry (Corg)
14
C,
Evidence for Younger Dryas
Sources
Maybe. Stable isotopes suggest a dip in SST,
but diatom assemblages do not. Upwelling
and productivity persistent throughout YD.
No. SST does not change, and changes in productivity
are out of synch with YD. Upwelling reduced relative
to modern, but not relative to B-A.
Ortiz et al., 1997;
Sancetta et al., 1992;
Pisias et al., 2001; Mix et al., 1999; Ortiz
et al., 1997; Sancetta et al., 1992; Sabin
and Pisias, 1996
problems and limited resolution of the data. It is not known
precisely how the climate may have changeddthere appears to
have been a decrease in atmospheric temperature, but whether
precipitation regimes shifted back to their LGM positions or not is
unclear. Climate change was evidently insufficiently intense or
sustained to have had widespread ecological impacts. Also, it was
not the only event of its kind, and the Younger Dryas may have been
another variable alongside the broader effects of post-LGM deglaciation and climatic change.
2.4. Marine environments
Marine paleoenvironmental records along the West Coast are
often well constrained temporally, with laminated deep-water
basin sediments that can provide decadal or century scale resolution. Cores from these basins provide several proxies for a variety of
long-term environmental fluctuations, including radiolarian and
foraminiferal assemblages and faunal isotopic signatures sensitive
to changes in sea surface temperatures (SST) and nutrients; sediment structures that reveal changes in circulation and productivity;
and organic residues, isotopes, and trace elements that respond to
changes in circulation, upwelling, temperature, productivity, and
terrigenous sediment input (Table 2).
Today, marine climate of the West Coast is largely controlled by
currents originating with the North Pacific Gyre, which splits as it
encounters the continental shelf near the coasts of Washington and
Oregon. The California Current flows southward along the California Coast, driven by air masses moving between the North
Pacific high-pressure system and a low-pressure system over the
American Southwest. As the California Current moves southward,
offshore winds and the force of the earth’s rotation push surface
waters westward, allowing deeper, nutrient rich waters to come to
the surface and fostering highly productive marine ecosystems.
Southerly currents and upwelling are strongest during the spring,
when winds are highest (Lynn and Simpson, 1987; Marchesiello
et al., 2003). Upwelling decreases or ceases entirely during the
fall and winter along much of the West Coast (Huyer, 1983; Capet
et al., 2004). The exception is southern California, where complicated circulation patterns caused by the local geography produce at
least intermittent upwelling for most of the year (Harms and
Winant, 1998; Bray et al., 1999).
Marine environments of the West Coast appear to have been
more sensitive than terrestrial ones to fluctuations in climate
throughout the late Pleistocene and Holocene. The southward
displacement of the polar jet stream during the LGM was accompanied by changes in those pressure systems that drive the North
Pacific Gyre. These changes dampened the winds that drive the
California Current, which slowed or stopped during the LGM. As
a result, there was little upwelling along the coast, which is
essential to modern marine productivity (Sabin and Pisias, 1996;
Ortiz et al., 1997; Lyle et al., 2000). Modern circulation and
upwelling patterns began to develop about 15,000 BP (Sabin and
Pisias, 1996), but it is unclear how North Pacific air massesdand
consequently the California Currentdresponded to the onset of the
Younger Dryas. Mix et al. (1999) suggested that atmospheric teleconnections transferred some effects of the Younger Dryas event to
the North Pacific, but that changes in North Pacific waters became
self-sustaining and were highly variable.
At some sites, records of late Pleistocene SSTs correlate
remarkably well with records of the Greenland Ice Cores suggesting
that they may have responded more directly to Younger Dryas
changes. Just north of the study area, off the coast of Vancouver
Island, core JT96-09PC shows a drop in SST from about 9 C during
the Bølling-Allerod to about 6 C during the Younger Dryas, with
a rapid rise to about 12 C by 10,700 BP (Kienast and McKay, 2001).
The ODP-1019 core near the OregoneCalifornia border shows
a similar pattern, with SST during the Younger Dryas 2e3 C lower
than during the Bølling-Allerod and Early Holocene, but substantial
variability during the entire deglacial (Mix et al., 1999; Barron et al.,
2003). At these sites SST does not return to full glacial conditions,
however, and the Younger Dryas may best be described as the
lowest of several late Pleistocene SST depressions.
At ODP-893 in the Santa Barbara Basin, ocean temperatures
recorded in v18O signatures and faunal assemblages dropped by
about 4 C during the coldest part of the GISP Younger Dryas,
around 12,400 BP. Temperatures appear to have ameliorated
quickly, with warming beginning w11,500 BP, but upwelling and
modern circulation patterns may not have resumed until
w11,200 BP (Hendy et al., 2002). Just outside the Santa Barbara
Basin at ODP-1017, Younger Dryas SSTs also dropped by as much as
4 C, but there were significant fluctuations throughout the
deglacial period (Seki et al., 2002; Hendy et al., 2004).
Sea surface temperatures off the Pacific Coast of the Baja Peninsula and in the Gulf of California responded very differently to the
onset of the Younger Dryas, where the suppression of the California
Current allowed greater influence from southern waters, and the
LGM was characterized by El Niño-like conditions. Faunal assemblages suggest frequent warm-water incursions, indicating that
spring upwelling was suppressed and productivity lower. However,
this pattern is not as strong during the Younger Dryas as it was during
the LGM (Sancetta, 1995; Pride et al., 1999; Barron et al., 2004, 2005).
At other sites, there appears to have been little SST response to
the Younger Dryas. At site W8709A-08, located offshore near the
OregoneCalifornia border, there is no evidence in either stable
isotopes or faunal assemblages to suggest a change in SST (Sancetta
et al., 1992). In core W8709A-13, located closer to shore at the same
latitude, radiolaria assemblages suggest a decrease in the strength
of the eastern boundary current and, hence, upwelling, but stable
isotopes suggest no change in SST (Sancetta et al., 1992; Pisias et al.,
2001). The transition from the glacial to interglacial appears to have
been gradual at some sites, with faunal assemblages indicative of
the eastern boundary current and upwelling beginning to develop
around 15,000 BP (Sabin and Pisias, 1996). Gardner et al. (1997) also
found no systemic breaks in the glacialeinterglacial transition
trends in either SST or upwelling along a series of California cores.
Marine productivity may have been less responsive to the
Younger Dryas and more variable over short distances than SST. Off
the coast near the OregoneCalifornia border, productivity maxima
and minima at W8709A-08 and W8709A-13 do not correlate well
with the Younger Dryas. Productivity begins to increase around
14,000 BP (Sancetta et al., 1992; Mix et al., 1999). Similarly, three
cores off the southern tip of Baja California suggest just small
declines in upwelling and productivity during the Younger Dryas
(Ganeshram et al., 1995; Dean et al., 2006). Mix et al. (1999) suggested that, although surface waters may have responded to
Younger Dryas global climate changes, intermediate and deep
ocean waters may have responded to separate events locally or in
the south Pacific.
The southern California cores, which generally correlate most
closely with the Greenland record, have more obvious productivity
responses. At ODP-893, Hendy et al. (2002) suggested that
upwelling and probably productivity were low between 12,600 and
11,200 BP. Productivity is also reduced during the Younger Dryas at
ODP-1019 off northern California and does not appear to increase
until between 10,800 and 10,000 BP (Barron et al., 2003). Within
the Gulf of California, two cores close to each other but at different
depths demonstrate the variability of response to the Younger
Dryas. Core MD02-2512, located 477 m below the surface, shows
little change in productivity during the Younger Dryas, while core
MD02-2515, 881 m below the surface, has a much more
pronounced decrease in productivity (Cheshire et al., 2005).
While the details of these marine records and their implications
for biological systems are still being improved and debated, few
studies have addressed macrofaunal responses to the end of the
Pleistocene. In general, the kelp forests and other nearshore environments important to people on the West Coast during the
Holocene do well during periods of sea level rise. Terrestrial sediments transported to the coast are funneled away from the shore by
newly drowned streambeds, leaving the nearshore environment
relatively clear of sediment. As river mouths are inundated, they
form estuaries and bays that support abundant and diverse
Fig. 4. Locations of sites with
contemporary shorelines.
14
471
resources. On the West Coast, the rocky surface needed to support
kelp forests and rocky intertidal shellfish was at a maximum during
or soon after the Younger Dryas (Kinlan et al., 2005; Masters and
Aiello, 2007), although many fully mature, productive estuaries
may not have developed until the Early or Middle Holocene
(Masters and Aiello, 2007). These general patterns would have been
tempered locally by nearshore bathymetry, which is highly variable
along the West Coast, as well as fluctuating SST and productivity.
3. The archaeology of the Younger Dryas along the West Coast
Few archaeological problems are as challenging as those presented by the global effects of post-glacial sea level rise and the
flooding of the world’s continental shelves on the distribution of
late Pleistocene archaeological sites (Erlandson, 2001). The very
coastlinesdand vast tracts of the adjacent coastal lowlandsd
along which early maritime peoples would have travelled and
lived are now deeply submerged off the West Coast, where high
wave energy has probably subjected most of them to heavy
marine erosion. There are few archaeological sites and they
represent only one portion of the settlement system. Thus, each
new site forces reevaluation of existing interpretations, making
the terminal Pleistocene archaeology of the West Coast dynamic
and difficult to reconstruct.
The West Coast’s advantage over many other coastal areas
around the world is its relatively steep bathymetry, which limited
the lateral movement of coastlines during post-glacial sea level
rise. The width of the continental shelf varies considerably up and
down the coast, however, and many shorelines migrated 20 km or
more during the past 20,000 years (Fig. 2). These and other
preservation problems leave archaeologists with limited options
in trying to understand the terminal Pleistocene history of human
occupation along the West Coast. One option is underwater
C dates within or immediately after the Younger Dryas on California’s Northern Channel Islands. Note the distances between these sites and their
472
Table 3
West Coast archaeological sites dating to or shortly after the Younger Dryas. All dates were calibrated using calib6.0. A reservoir correction of 225 35 (southern California
sites) or 155 51 (Baja California sites) was applied to all dates obtained from shell.
Site
Name
Radiocarbon dates
CA-SMI-678
Cardwell Bluffs
CA-SMI-679
CA-SMI-261
Cardwell Bluffs
Daisy Cave
CA-SRI-173
CA-SRI-512W
Arlington Skeleton
CA-SRI-706
PAIC-44
SRI Bluffs
Cerro Pedregoso
PAIC-49
Richard’s Ridge
10,500
10,650
10,650
10,650
10,750
10,600
10,700
10,390
10,960
10,000
10,045
10,090
10,150
10,155
10,200
10,460
10,520
10,157
10,095
10,745
10,420
10,250
10,380
9970
50 (shell)
40 (shell)
40 (shell)
55 (shell)
55 (shell)
70 (shell)
90 (shell)
130 (charcoal)
80 (human bone collagen)
30 (Goose bone)
40 (Goose bone)
50 (charcoal)
40 (Goose bone)
30 (Charred twig)
45 (charcoal)
65 (shell)
30 (shell)
30 (charcoal)
35 (charcoal)
25 (shell)
50 (shell)
60 (charcoal)
60 (charcoal)
25 (charcoal)
archaeology, which holds some promise but is in its infancy
within the study area. Another option is to search areas of narrow
continental shelf for upland or interior manifestations of coastal
settlement, an approach that has been highly successful when
applied to limited areas along the coasts of Alta and Baja
California.
Currently, just nine sites along the West Coast have been
securely dated to the Younger Dryas or the period immediately
after it. These include four sites on San Miguel Island (CA-SMI-261,
CA-SMI-678, CA-SMI-679, and CA-SMI-701) and three on Santa
Rosa Island (CA-SRI-512W, CA-SRI-173, CA-SRI-706), all found on
what was then western Santarosae Island (Fig. 4, Table 3)
(Erlandson et al., 2008, 2011; Rick and Erlandson, in press). They
also include two shell middens (PAIC-44 and PAIC-49) on Isla
Cedros, Baja California (Fig. 5, Table 3) (see Des Lauriers, 2006a,
Fig. 5. Locations of early sites on Isla Cedros. Because of lower resolution topographic
and bathymetric data, these shoreline reconstructions are more approximate than
those to the north. Nonetheless, these early sites were certainly located a substantial
distance from the coast.
Calibrated dates BP
References
11138e11417
11250e11739
11250e11739
11240e11754
11344e11973
11194e11745
11243e11961
11808e12594
w13000e12000
11304e11622
11382e11761
11397e11966
11684e11999
11703e11988
11749e12076
11092e11493
11218e11676
11704e11989
11469e11962
11616e12103
11122e11425
11753e12376
12038e12429
11268e11414
Rick and Erlandson, in press; Erlandson et al., 2011
Rick and Erlandson, in press; Erlandson et al., 2011
Erlandson et al., 1996; Rick et al., 2001
Johnson et al., 2007
Erlandson et al., 2011
Rick and Erlandson, in press
Des Lauriers, 2006a, 2010
Des Lauriers, 2006a,b, 2010
2010; Erlandson et al., 2008). This limited number of sites does
not provide a comprehensive perspective on the human adaptations during this time, but both the location and nature of these
sites give important context about the people living in the
temperate coastal regions of western North America during the
Younger Dryas.
3.1. Younger Dryas Paleocoastal sites from the Northern Channel
Islands
In 1959, in Arlington Canyon on the northwest coast of Santa
Rosa Island, Orr (1962a,b, 1968) identified a few isolated human
bones eroding out of a paleosol buried w11 m below the surface of
the canyon wall. The Arlington Springs site (CA-SRI-173) was
located adjacent to a bedrock sill where, today, freshwater comes to
the surface near the of perennial Arlington Creek. Orr obtained
dates of w10,000 14C BP (w12,000 BP) for Arlington Man, an age
later confirmed by Berger and Protsch (1989). More recent work at
the site produced no additional human remains, but a thorough
re-dating of the section and the human bone now suggests that
Arlington Man died closer to 13,000 years ago, essentially
contemporaneous with Clovis (Johnson et al., 2002, 2007). A few
small fragments of chipped stone tool-making debris were
reportedly found in the same soil as the human bones, but no
diagnostic artifacts or archaeological faunal materials were
recovered.
In the 1980s, a terminal Pleistocene occupation was tentatively
identified by Daniel Guthrie and Pandora Snethkamp for a lowdensity shell midden deposit near the base of a deeply buried
and well-stratified sequence at Daisy Cave (CA-SMI-261) on the
northeast coast of San Miguel Island. Subsequent work directed by
Erlandson (2007) confirmed the age and cultural context of this
midden, demonstrating that it dates near the end of the Younger
Dryas about 11,600 years ago. Although Daisy Cave has produced an
important assemblage of Paleocoastal artifacts, including shell
beads, woven sea grass, bipointed bone fish gorges, etc., and faunal
remains dated between about 10,200 and 8500 BP (Erlandson et al.,
1996; Rick et al., 2001), the Younger Dryas component appears to
result from a brief visit by earlier Paleocoastal peoples. Several
years of meticulous excavations in this terminal Pleistocene
component (Stratum G) produced just a few undiagnostic chipped
stone tools, tool-making debris, and small amounts of marine shell
from rocky shore species, including red abalone (Haliotis rufescens),
black turban (Chlorostoma [Tegula] funebralis), California mussel
(Mytilus californianus), giant chiton (Cryptochiton stelleri), and
unidentified crab (Decapoda). Erlandson and Jew (2009) suggested
that a Channel Island Barbed Point found near the base of the
midden in the 1960s (Rozaire, 1978) may be associated with this
earliest Paleocoastal component. Direct AMS 14C dating of an
extinct flightless duck (Chendytes lawi) bone from deep in the Daisy
Cave sequence produced an age of 11,150 to 10,280 BP (Jones et al.,
2008a), some of the earliest evidence for human exploitation of
Chendytes along the Pacific Coast.
The Cardwell Bluffs sites (CA-SMI-678, -679, and -701) are
located on an uplifted marine terrace near the east end of San
Miguel Island (Erlandson and Braje, 2008; Erlandson et al., 2008,
2011). Argillic soils and a dearth of sedimentation in this area
exposed cobbles of high-quality chert that attracted Paleocoastal
peoples. This large site complex is heavily eroded and hundreds of
chipped stone bifaces have been collected from the surface. Most of
these are fragments of leaf-shaped biface preforms made from local
Monterey and Cico cherts (Erlandson et al., 2008), but dozens of
chipped stone crescents and distinctive long-stemmed points have
also been found (Erlandson et al., 2011). Given the lack of terrestrial
game alternatives, Erlandson and Braje (2008) suggested that the
crescents served as transverse dart points utilized in bird hunting.
The stemmed points have not yet been fully described, but they
include 31 Channel Island Barbed types (see Justice, 2002) and 21
Amol points, a generally serrated variety of unbarbed points. Both
crescents and stemmed points have been found closely associated
with intact midden loci, including a few specimens found in situ.
At each of these Cardwell Bluffs sites, intact patches of soil
contain shallow shell middens. Six separate midden loci have now
been identified and well-preserved shells from all have been AMS
14
C dated between about 12,200 and 11,400 BP (Erlandson et al.,
2011). It now appears that Paleocoastal peoples visited the Cardwell Bluffs area on multiple occasions near the end of the Younger
Dryas, repairing hunting equipment and consuming shellfish
carried to the sites from shorelines located roughly 1.5e2.0 km
away. Similar to Daisy Cave, these terminal Pleistocene middens
contain numerous marine shells, including red abalone, California
mussel, giant chiton, black turban snail, and other rocky intertidal
shellfish species. Black abalone (H. cracherodii) shells, a major
constituent of many Early Holocene middens on San Miguel Island,
are conspicuous by their near absence. This suggests that colder
Younger Dryas SST regimes recorded in the Santa Barbara Channel
may have affected local shellfish communities, changes that left
signatures in stronger human reliance on a colder water fauna.
Despite ample technological evidence for Paleocoastal hunting, no
bone has been recovered from the Cardwell Bluffs sites.
In contrast, CA-SRI-512W on Santa Rosa Island has yielded
extensive collections of bones and hunting technology dated to the
end of the Younger Dryas between w12,000 and 11,350 cal BP
(Erlandson et al., 2011). CA-SRI-512W is located on an uplifted
marine terrace w20 m above modern sea level, just east of the
mouth of Arlington Canyon. The Arlington Springs site and several
other sites dating to the earliest Holocene are located nearby (see
Erlandson, 1994; Erlandson et al., 1999). Portions of the site are
contained entirely within a paleosol sealed under >2 m of alluvium, with material eroding out of the terrace cliff onto the slope
below. The large faunal assemblage contained some fish and
marine mammal bones, but was dominated by bird bone from
several species of seabirds and waterfowldincluding a burned
Chendytes lawi bone (Erlandson et al., 2011). The recovery of a large
473
assemblage of bone but no marine shell is unique among early
archaeological sites on the Northern Channel Islands and unusual
for sites of any age.
CA-SRI-512W also produced a large assemblage of tools from
both the intact paleosol and the erosional slope below the site. This
included 19 crescents and 67 Channel Island Barbed points, but
none of the Amol points identified at the Cardwell Bluffs sites.
There was also less stone tool-making debris, suggesting a different
function for this site. Today, the mouth of Arlington Canyon is
a narrow but marshy environment, and this marshland may have
been more extensive during the Younger Dryas, when the coastal
plain was extended some 5e6 km to the north. This perhaps was
a hunting campdpossibly occupied in the winter when migratory
waterfowl tend to be found in Southern Californiadlocated
downwind of what may have been a rich seasonal resource of
migrating birds (Erlandson et al., 2011).
Rick and Erlandson (in press) recently identified another Paleocoastal site called CA-SRI-706 on the western end of Santa Rosa
Island. Similar to the Cardwell Bluffs sites, this is a lithic scatter
located on a high bluff overlooking the southwest coast of Santa
Rosa and the channel between Santa Rosa and San Miguel islands.
This large site is even more heavily eroded than the Cardwell Bluffs
sites, with rare patches of thin and truncated soil interspersed with
a low-density scatter of chipped stone tools in eroded areas. Rick
and Erlandson (in press) collected a few chipped stone crescents
from the surface of CA-SRI-706 and found a single large red abalone
shell embedded in an intact patch of the B-horizon at the site.
Dating of the red abalone shell produced a calibrated 14C age of
w11,500 years BP. Monterey chert cobbles have been found on the
beach and in terrace deposits below CA-SRI-706, and the site may
have served as a strategic overlook where hunting equipment was
manufactured and repaired.
Kennett et al. (2008) explored the hypothesis that a cosmic
impact affected Channel Island ecosystems and human populations
during the Younger Dryas (see Firestone et al., 2007). They noted
a nearly thousand year gap in the archaeological record of the
Channel Islands between w12,900 and 12,000 BP, which may be
the result of environmental disruptions. Much of this gap still exists
on the Channel Islands, but caution is warranted in interpreting it,
especially given that there is only one known archaeological site
(Arlington Springs) dated to w12,900 BP and there is a similar gap
in the archaeological record from about 11,400 to 10,200 BP. The
meaning of such gaps will only become clear when a larger sample
of terminal Pleistocene and earliest Holocene archaeological sites is
available
3.2. Younger Dryas shell middens on Isla Cedros, Baja California
Using a search strategy modeled after Erlandson’s work on the
Northern Channel Islands, Des Lauriers (2006a, 2010) identified
two shell middens on Isla Cedros off the Pacific Coast of Baja California (Fig. 5) with basal layers dating to the Younger Dryas. The
two sites are located several kilometers from the Younger Dryas
coastline (Fig. 5), adjacent to a freshwater spring and toolstone
outcrops, at a time when Isla Cedros was still connected to, or
perhaps just separated from, the mainland. The oldest site,
Richard’s Ridge (PAIC-49), has been 14C dated by both shell and
charcoal to w12,100 BP, but only a small portion of the stratified
midden remains intact (Des Lauriers, 2006a,b, 2010:83; Erlandson
et al., 2008). At the Cerro Pedregoso site (PAIC-44), the earliest
occupation appears to have begun around 11,700 BP. Much of the
site has eroded and is scattered down slope, but an intact section
reveals up to 1.5 m of midden deposited from the Younger Dryas
through the beginning of the Holocene. The Younger Dryas occupation, represented in just one excavation unit, appears to be less
474
intensive than in later periods (Des Lauriers, 2006a). Nonetheless
the early midden layers contain a diverse array of marine resources,
including California mussels, Pismo clams (Tivela stultorum), Venus
clams (Chione spp.), nearshore and kelp forest fishes, sea turtle
(Caretta caretta), and Guadalupe fur seal (Arctocephalus townsendi).
Among the unique artifacts found in the early levels at PAIC-44
were expedient tools made by flaking the edges of thick fragments of dense Tivela shells (Des Lauriers, 2006a:Fig. 7). Similar to
the Cardwell Bluffs sites, the early Isla Cedros shell middens have
produced numerous chipped stone bifacesdincluding a serrated
leaf-shaped point, a slightly-shouldered stemmed point, and
a contracting-stemmed pointdreminiscent of San Dieguito or
Western Pluvial Lakes Tradition (WPLT) assemblages (Des Lauriers,
2006a:Fig. 6).
3.3. West Coast wild cards: lithic sites and technological traditions
Although the archaeological sites discussed above are the only
true coastal sites along the West Coast firmly dated to the Younger
Dryas, a series of isolated fluted points and other lithic assemblages
provide intriguing evidence for the potential origins of the earliest
island sites. The distribution of fluted Clovis-like points in Alta and
Baja California has received considerable attention (Aschmann,
1952; Dillon, 2002; Rondeau et al., 2007; Des Lauriers, 2008). In
recent reviews, Rondeau et al. (2007) and Dillon (2002) eliminated
many purported fluted point finds but still identified roughly 50
fluted point localities in California, including four from coastal
areas. Most of these are isolated finds from surface contexts, none
are reliably dated, and many scholars believe they may be related to
a late movement of Clovis or other Paleoindian peoples into far
western North America. There is no reason to think that Paleoindians exploring the Great Basin or the American Southwest
would have stopped at the California border or to doubt that at least
some of them would have ventured as far as the coast. The four
fluted points from truly coastal areas of California include one
specimen from the western Santa Barbara Coast (Erlandson et al.,
1987), but none from the Northern Channel Islands. Along with
two specimens found on Isla Cedros (Des Lauriers, 2008, 2010:61),
these points may represent the westward edge of a broad expansion of fluted point peoples or technologies in North America.
A second class of early lithic artifacts, sometimes attributed to
the WPLT (such as San Dieguito, Lake Mojave, etc.), is characterized
by stemmed points often associated with chipped stone crescents.
Such associations are relatively common in early sites along the
West Coast and in the Great Basin (Tadlock, 1966; Jertberg, 1986;
Koerper and Farmer, 1987; Fenenga, 1992; Braje and Erlandson,
2008; Erlandson and Braje, 2008; Rick, 2008; Smith, 2008;
Erlandson et al., 2011). Several hundred crescents have been
found along the Alta California Coast, roughly half of them coming
from the Northern Channel Islands (Erlandson and Braje, 2008;
Mohr and Fenenga, 2010). Many of these crescents are from
surface contexts or poorly documented museum collections, but
securely-dated specimens now range in age between w12,000 and
8000 BP, a pattern that also appears to be true for the broader
Intermountain West (Erlandson and Braje, 2008; Beck and Jones,
2010). Given their broad geographic and temporal range, crescents were probably used for a variety of purposes. Suggestions
have ranged from surgical tools to projectile points, scrapers, and
zoomorphic amulets (Jertberg, 1986; Koerper et al., 1991; Fenenga,
1992), but many Great Basin and California archaeologists believe
that their close association with lakes and wetlands suggests a use
as transverse points used to hunt waterfowl. Regardless of their
function, the close association of chipped stone crescents with
stemmed projectile points in many coastal and interior sites of the
far western United States indicates a probable culturalehistorical
connection between early coastal and interior populations
(Erlandson and Braje, 2008), connections that may have begun by
the Younger Dryas or earlier.
Beck and Jones (2010) proposed that stemmed points and
crescents associated with the WPLT might be related to a coastal
migration into the New World, with coastal peoples moving eastward into the Great Basin even as Clovis peoples were moving
westward from the Great Plains and American Southwest.
Erlandson and Braje (in press) extended this scenario by pointing to
broad similarities in early stemmed point traditions of the Pacific
Rim, from Japan to California and South America. There are still
large and troubling gaps in the distribution of stemmed points
around the Pacific Rim, however, and further research will be
needed to confirm or reject such connections. With the discovery of
stemmed points associated with a pre-Clovis occupation at Paisley
Caves in south-central Oregon (see Gilbert et al., 2008), it now
seems likely that stemmed points predate Clovis or other fluted
point technologies in far western North America, supporting Beck
and Jones’ (2010) scenario (Erlandson et al., 2011).
4. Discussion and conclusions: Paleocoastal peoples and
Younger Dryas environments on the West Coast
Substantial amounts of paleoecological data now exist to help
reconstruct Younger Dryas changes in terrestrial and marine environments along the West Coast, but the archaeological record for
this time period is both sparse and discontinuous. A variety of
paleoecological records suggest that the Younger Dryas was
marked by generally cooler climatic conditions and SSTs along the
West Coast, relative to either the Bølling-Allerod or the earliest
Holocene, with lower precipitation to the north and greater rainfall
to the south, and some resulting vegetation changes. For humans,
these changes were probably relatively subtle compared to major
changes in shorelines and coastal habitats, even if sea level rise
slowed substantially during the Younger Dryas.
For the southern Northwest Coast, little is known about human
adaptations to the coastal zone. There are a few lithic sites such as
Indian Sands (35-CU-67C) on the southern Oregon coast and some
isolated fluted points that may date to the terminal Pleistocene (see
Davis et al., 2004; Hall et al., 2005; Erlandson et al., 2008;
Erlandson, 2009), but relatively little can be said about human
coastal settlement or adaptations to the Younger Dryas in this area.
If people were present they lived in highly dynamic coastal environments. Although a southward shift in precipitation patterns
may have created a less lush environment during the Younger
Dryas than is presently known, there is no suggestion that it was
a particularly harsh environment compared to many others in
North America. Today, wet climates and acidic soils along the
southern Northwest Coast lead to poor site preservation, and heavy
vegetation tends to reduce site visibility. The western Washington
coast also experienced some of the greatest lateral shoreline
movements of any area north of Baja California (Fig. 2), conditions
under which early coastal sites are less likely to be preserved. Given
the presence of terminal Pleistocene coastal sites along the
northern Northwest Coast (Fedje and Mathewes, 2005; Erlandson
et al., 2008), it seems likely that the current lack of definitive
evidence for Younger Dryas occupation along the Washington,
Oregon, and northern California coasts is related to the tectonic
history of the Cascadia Subduction Zone, where periodic subsidence earthquakes, tsunamis, and erosion (Goldfinger et al., 2003)
may have destroyed evidence that existed for Paleoindian peoples
living along the coast (Erlandson et al., 1998, 2008; Moss and
Erlandson, 1998; Punke and Davis, 2006).
To the south, in Alta and Baja California, a growing number of
terminal Pleistocene shell middens provide important details about
the life ways of people living along the West Coast during the
Younger Dryas. Some of these Paleocoastal peoples were harvesting
shellfish and other marine resources and, based on the colonization
of the Northern Channel Islands, using boats around the same time
that Clovis peoples were hunting the last of the Pleistocene
megafauna and pursuing other resources in interior areas of North
America. At the end of the Younger Dryas, when sea levels were
about 60e55 m below modern, the Northern Channel Islands were
over 20 km from the mainland at their nearest point on the east end
of Santarosae (now Anacapa Island) (Fig. 4). The coastlines of
western Santarosae (San Miguel and western Santa Rosa) were
even further from the mainland coast. The passage across the Santa
Barbara Channel is not an easy one, and it is likely that these early
maritime peoples had relatively sophisticated watercraft. The large
number of bifaces, crescents, and sophisticated stemmed projectile
points in the earliest Channel Island sites suggests that there was
a hunting component to Paleocoastal occupations that is not yet
fully represented in faunal assemblages (Erlandson et al., 2005,
2009; Erlandson and Jew, 2009).
Significantly, the known Paleocoastal sites on the Channel
Islands and Isla Cedros are not located adjacent to Younger Dryas
shorelines, where they would almost certainly have been lost to sea
level rise and coastal erosion. Most are situated several kilometers
from their contemporary coastlines near important landscape
features that drew coastal peoples into the interior. Plant resources
may have been one of these attractions, but little evidence for
Younger Dryas plant use has yet been found at the sites. Perhaps the
main attractions these sites offered was their proximity to freshwater springs (e.g. Arlington Springs and the Isla Cedros sites),
sources of chert or other rock types used to make chipped stone
tools (e.g. Cardwell Bluffs and Isla Cedros sites), or caves that
provided shelter from the elements (e.g. Daisy Cave). CA-SRI-512W
may represent subsistence activities related to a marsh environment that became increasingly rare on the narrower Holocene
continental shelf. Despite their distance from the coast, the food
remains and technologies found in most of these sites indicate
a strong reliance on marine resources, including shellfish and
probably marine mammals, fish, birds, and seaweeds. Given their
distance from Younger Dryas coastlines, the lack of vertebrate
remains at several sites may result from differential butchering and
transport of various animals.
What is not yet known is whether these early Channel Island
and Isla Cedros sites represent a broader coastal adaptation
present along the West Coast during the Younger Dryas. Early
island locales may have offered especially productive marine
resourcesdprominently including pinniped haulouts and bird
colonies attracted by the lack of large terrestrial predators. Many
mainland coastal areas may have also had attractive estuaries, kelp
forest, and other marine ecosystems, but more productive terrestrial ecosystems that offered a wider array of plant resources and
land mammals may have called for a somewhat different
adaptation.
To explain the overall variability in the terminal Pleistocene
archaeology of the West Coast and the adjacent interior, archaeologists have presented several hypotheses. Some have argued for
two opposing (but not necessarily competing) adaptations on the
West Coast during its earliest occupationdone a coastal Milling
Stone adaptation based largely on “shellfish and seeds” (Erlandson,
1991, 1994; Jones et al., 2002), and another associated with fluted
points and oriented more toward terrestrial adaptations. Others
have focused on the differences between stemmed and fluted
projectile points, suggesting that these represent two different
technological traditions, one from the coast and the other from the
interior of North America (Beck and Jones, 2010; Erlandson and
Braje, in press). The earliest Isla Cedros and Channel Islands sites
475
suggest that some Paleocoastal peoples had diversified and relatively sophisticated maritime economies and technologies,
including leaf-shaped biface and stemmed point traditions that
may or may not be descended from Clovis.
Understanding the archaeological record of the Younger
Dryas also benefits from a brief summary of what followed.
Other than the Cerro Pedregoso site on Isla Cedros (and possibly
Daisy Cave), there are very few sites along the West Coast
with occupations securely dated to the millennium or so
(11,400e10,200 BP) immediately after the end of the Younger
Dryas. However, the period between 10,200 and 9000 BP saw
a significant increase in the number of dated Paleocoastal sites
in southern and central California, with dozens of well-dated
sites from the Northern Channel Islands and the mainland
coasts of San Diego, Orange, Santa Barbara, and San Luis Obispo
counties and Baja California (see Laylander and Moore, 2006;
Erlandson et al., 2007, 2008).
Many of these sites along California’s mainland coast are associated with the appearance of the Milling Stone Horizon, which
emerges during the Early Holocene (Erlandson, 1994; Jones et al.,
2002). Coastal and near-coastal sites are still characterized by
a high dependence on marine resources, but plant foods and plantprocessing technologies appear to be very different from those on
the islands. Notable sites include the Cross Creek site (CA-SLO1797; Fitzgerald, 2000; Jones et al., 2002), the Diablo Canyon site
(CA-SLO-2; Greenwood, 1972; Jones et al., 2008b), the Surf site (CASBA-931; Glassow, 1996), the Irvine site (CA-ORA-64; Koerper,
1981), and the Harris site (CA-SDI-1966; Warren, 1966, 1967)
each probably first occupied between w10,000 and 9000 BP. These
early mainland sites suggest a broad-spectrum diet focused on
shellfish and plant seeds, supplemented with rabbit, deer, and
other resources from both the land and sea. Artifacts include
eccentric crescents similar to those used during the Younger Dryas,
as well as leaf-shaped projectile points, milling stones, and Olivella
shell beads (Erlandson et al., 2007; Glassow et al., 2007; Jones et al.,
2007).
Does the expansion in the number of early sites along the West
Coast reflect growing human populations, the greater preservation
and visibility of sites located adjacent to shorelines closer to the
modern coast, or both? In the authors’ view, only further research
will answer this question, including a systematic search for coastal
sites of Younger Dryas age elsewhere along the West Coast. Further
progress in the archaeology of the Younger Dryas should focus on
several key research areas:
1. High-resolution paleoecological research on the Younger Dryas
designed to document specific environmental changes (or lack
thereof) are required to better understand their potential
effects on humans. Studies such as Kennett et al. (2008) and
Vacco et al. (2005) are steps in this direction, but it is important
to link regional paleoenvironmental records to specific faunal,
floral, and isotopic records from archaeological sites wherever
possible.
2. On the Northern Channel Islands, additional work on Paleocoastal sites should be focused on determining if gaps in the
occupational
sequence
(w13,000e12,200
BP,
and
w11,400e10,200 BP) are the result of sampling error, differential preservation, or the effects of Younger Dryas environmental changes.
3. To determine if other areas along the West Coast were occupied
during the Younger Dryas, further survey work is needed in
areas where the offshore bathymetry is relatively steep and
marine productivity was high. Creative new approaches to the
archaeology of the coastal uplandsdpotentially modeled on
Channel Island and Isla Cedros case studiesdmay broaden
476
understanding of Paleocoastal occupations and the use of
wider coastal landscapes.
4. High resolution local shoreline reconstructions that consider
the ecology of the shorelines as well as their shape are crucial
to modeling early sites locations on the submerged continental
shelves of the West Coast. Without detailed mapping and
modeling to narrow the search, underwater surveys for
offshore Paleocoastal sites are unlikely to be productive.
5. Finally, an understanding of the meaning and relationship
between early fluted and stemmed point traditionsdand the
antiquity and origins of the twodwill require better chronological control of lithic assemblages that appear to date to the
terminal Pleistocene.
Acknowledgments
We thank Ted Goebel and Lawrence Straus for inviting us to
participate in their 2010 Society for American Archaeology
symposium and this volume dedicated to the archaeology of the
Younger Dryas. We are also indebted to numerous colleagues who
have contributed to our thinking about Paleocoastal occupations
along the West Coast, including Todd Braje, Loren Davis, Matt Des
Lauriers, Gerrit Fenenga, Mike Glassow, Bill Hildebrandt, John
Johnson, Terry Jones, Doug Kennett, Lee Lyman, and Madonna
Moss. Finally we are indebted to anonymous reviewers, the editors,
and the production staff of Quaternary International for their help in
revising and publishing this paper.
References
Adam, D.P., West, G.W., 1983. Temperature and precipitation estimates through the
last glacial cycle from Clear Lake, California, pollen data. Science 219, 168e170.
Adam, D.P., Robinson, S.W., 1988. Palynology of Two Upper Quaternary Cores from
Clear Lake, Lake County, California. U.S. Geological Survey Professional Paper
1363. United States Government Printing Office, Washington, D.C.
Adam, D.P., Sims, J.D., Throckmorton, C.K., 1981. 130,000-yr continuous pollen
record from Clear Lake, Lake County, California. Geology 9, 373e377.
Amante, C., Eakins, B.W., 2009. ETOPO1 1 Arc-Minute Global Relief Model: Procedures, Data Sources, and Analysis. NOAA Technical Memorandum NESDIS
NGDC-24.
Anderson, R.S., 1990. Holocene forest development and paleoclimates within the
central Sierra Nevada, California. Journal of Ecology 78 (2), 470e489.
Anderson, R.S., Starratt, S., Bruner Jass, R.M., Pinter, N., 2010. Fire and vegetation
history on Santa Rosa Island, Channel Islands, and long-term environmental
change in southern California. Journal of Quaternary Science 25 (5), 782e797.
Anundson, K., Abella, S., Leopold, E., Stuvier, M., Turner, S., 1994. Late-Glacial and
Early Holocene sea-level fluctuations in the central Puget Lowlands, Washington, inferred from lake sediments. Quaternary Research 42 (2), 149e161.
Aschmann, H., 1952. A fluted point from Central Baja California. American Antiquity
17 (3), 262e263.
Bard, E., Hamelin, B., Fairbanks, R., 1990. UeTh ages obtained by mass spectrometry
in corals from Barbados: sea level during the past 130,000 years. Nature 346
(6283), 456e458.
Bard, E., Hamelin, B., Arnold, M., Montaggioni, L., Cabioch, G., Faure, G., Rougerie, F.,
1996. Deglacial sea-level record from Tahiti corals and the timing of global
meltwater discharge. Nature 382 (6588), 241e244.
Barnosky, C.W., 1981. A record of late Quaternary vegetation from Davis Lake,
southern Puget Lowland Washington. Quaternary Research 16 (2), 221e239.
Barnosky, C.W., 1985a. Late Quaternary vegetation near Battle Ground Lake,
southern Puget Trough, Washington. Geological Society of America Bulletin 96,
263e271.
Barnosky, C.W., 1985b. Late Quaternary vegetation in the southwestern Columbia
basin, Washington. Quaternary Research 23 (1), 109e122.
Barron, J.A., Heusser, L.E., Herbert, T., Lyle, M., 2003. High-resolution climatic
evolution of coastal northern California during the past 16,000 years. Paleoceanography 18 (1), 1020e1035.
Barron, J.A., Bukry, D., Bischoff, J.L., 2004. High resolution paleoceanography of the
Guaymas Basin, Gulf of California, during the past 15,000 years. Marine
Micropaleontology 50 (3e4), 185e207.
Barron, J.A., Bukry, D., Dean, W.E., 2005. Paleoceanographic history of the Guaymas
Basin, Gulf of California, during the past 15,000 years based on diatoms, silicoflagellates, and biogenic sediments. Marine Micropaleontology 56 (3e4), 81e102.
Bartlein, P.J., Anderson, K.H., Anderson, P.M., Edwards, M.E., Mock, C.J.,
Thompson, R.S., Webb, R.S., Webb III, T., Whitlock, C., 1998. Paleoclimate
simulations for North America over the past 21,000 years: features of the
simulated climate and comparisons with paleoenvironmental data. Quaternary
Science Reviews 17, 549e585.
Beck, C., Jones, G.T., 2010. Clovis and Western Stemmed: population migration and
the meeting of two technologies in the Intermountain West. American Antiquity 75 (1), 81e116.
Berger, R., Protsch, R., 1989. UCLA radiocarbon dates XI. Radiocarbon 31 (1),
55e67.
Blanchet, C.L., Thouveny, N., Vidal, L., Leduc, G., Tachikawa, K., Bard, E., Beaufort, L.,
2007. Terrigenous input response to glacial/interglacial climatic variations over
southern Baja California: a rock magnetic approach. Quaternary Science
Reviews 26 (25e28), 3118e3133.
Booth, D.B., Troost, K.G., Clague, J.J., Waitt, R.B., 2004. The Cordilleran Ice Sheet. In:
Gillespie, A.R., Porter, S.C., Atwater, B.F. (Eds.), The Quaternary Period in the
United States. Elsevier, New York, NY, pp. 17e44.
Braje, T.J., Erlandson, J.M., 2008. Early maritime technology from western San
Miguel Island, California. Current Research in the Pleistocene 25, 61e63.
Bray, N.A., Keyes, A., Morawitz, W.M.L., 1999. The California Current system in the
Southern California Bight and the Santa Barbara Channel. Journal of Geophysical Research 104 (C4), 7695e7714.
Briles, C.E., Whitlock, C., Bartlein, P.J., 2005. Postglacial vegetation, fire, and climate
history of the Siskiyou Mountains, Oregon, USA. Quaternary Research 64 (1),
44e56.
Capet, X.J., Marchesiello, P., McWilliams, J.C., 2004. Upwelling response to coastal
wind profiles. Geophysical Research Letters 31, L13311.
Cheshire, H., Thurow, J., Nederbragt, A., 2005. Late Quaternary climate change
record from two long sediment cores from Guaymas Basin, Gulf of California.
Journal of Quaternary Science 20 (5), 457e469.
Cwynar, L.C., 1987. Fire and the forest history of the North Cascade Range. Ecology
68 (4), 791e802.
Daniels, M.L., Anderson, R.S., Whitlock, C., 2005. Vegetation and fire history since
the Late Pleistocene from the Trinity Mountains, northwestern California, USA.
The Holocene 15 (7), 1062e1071.
Davis, L.G., Punke, M.L., Hall, R.L., Fillmore, M., Willis, S.C., 2004. A late Pleistocene
occupation on the southern coast of Oregon. Journal of Field Archaeology 29,
7e16.
Dean, W.E., Zheng, Y., Ortiz, J.D., Van Geen, A., 2006. Sediment Cd and Mo accumulation in the oxygen-minimum zone off western Baja California linked to
global climate over the past 52 kyr. Paleoceanography 21 (4), PA4209.
Des Lauriers, M.R., 2006a. Terminal Pleistocene and Early Holocene occupants of
Isla de Cedros, Baja, California. Journal of Island and Coastal Archaeology 1 (2),
255e270.
Des Lauriers, M.R., 2006b. Isla Cedros. In: Laylander, D., Moore, J.D. (Eds.), The
Prehistory of Baja California: Advances in the Archaeology of the Forgotten
Peninsula. University Press of Florida, Gainesville, FL, pp. 153e156.
Des Lauriers, M.R., 2008. A Paleoindian fluted point from Isla Cedros, Baja California.
Journal of Island and Coastal Archaeology 3 (2), 271e276.
Des Lauriers, M.R., 2010. Island of Fogs: Archaeological Investigations of Isla Cedros,
Baja California. University of Utah Press, Salt Lake City, UT.
Dillon, B.D., 2002. California Palaeoindians: lack of evidence, or evidence of a lack?
In: Wallace, W.J., Riddell, F.A. (Eds.), Essays in California Archaeology:
a Memorial to Franklin Fenenga. Archaeological Research Facility, University of
California, Berkeley, Berkeley, CA, pp. 110e128.
Erlandson, J.M., 1991. Shellfish and seeds as optimal resources: early Holocene
subsistence on the Santa Barbara Coast. In: Erlandson, J.M., Colten, R.H. (Eds.),
Hunter-gatherers of Early Holocene Coastal California. University of California
Institute of Archaeology, Los Angeles, pp. 89e101.
Erlandson, J.M., 1994. Early Hunter-Gatherers of the California Coast. Plenum, New
York, NY.
Erlandson, J.M., 2001. The archaeology of aquatic adaptations: paradigms for a new
millennium. Journal of Archaeological Research 9 (4), 287e350.
Erlandson, J.M., 2007. Sea change: the Paleocoastal occupations of Daisy Cave. In:
Neusius, S.W., Gross, G.T. (Eds.), Seeking Our Past: An Introduction to North
American Archaeology. Oxford University Press, Oxford, pp. 135e143.
Erlandson, J.M., 2009. Contextual and chronological hygiene in interpreting Paleocoastal sites of North America’s Pacific Coast. Quaternary Science Reviews 28
(23/24), 2539e2541.
Erlandson, J.M., Braje, T.J., 2008. Five crescents from Cardwell: context and function
of eccentric crescents from CA-SMI-679, San Miguel Island, California. Pacific
Coast Archaeological Quarterly 40 (1), 35e46.
Erlandson, J.M., Braje, T.J. From Asia to the Americas by boat? Paleogeography,
paleoecology, and stemmed points of the Northwest Pacific. Quaternary International, in press.
Erlandson, J.M., Jew, N., 2009. An early maritime biface technology at Daisy Cave,
San Miguel Island, California: reflections on sample size, site function, and other
issues. North American Archaeologist 30 (2), 145e165.
Erlandson, J.M., Cooley, T.G., Carrico, R., 1987. A fluted projectile point fragment
from the southern California coast: chronology and context at CA-SBA-1951.
Journal of California and Great Basin Anthropology 9 (1), 120e128.
Erlandson, J.M., Kennett, D.J., Ingram, B.L., Guthrie, D.A., Morris, D.P., Tveskov, M.A.,
West, G.J., Walker, P.L., 1996. An archaeological and paleontological chronology
for Daisy Cave (CA-SMI-261), San Miguel Island, California. Radiocarbon 38 (2),
355e373.
Erlandson, J.M., Tveskov, M.A., Byram, S., 1998. The development of maritime
adaptations on the southern Northwest Coast of North America. Arctic
Anthropology 35 (1), 6e22.
Erlandson, J.M., Braje, T.J., Rick, T.C., 2005. Beads, bifaces, and boats: an early
maritime adaptation on the south coast of San Miguel Island, California.
American Anthropologist 107, 677e683.
Erlandson, J.M., Rick, T.C., Jones, T.L., Porcasi, J.F., 2007. One if by land, two if by sea:
who were the first Californians? In: Jones, T.L., Klar, K.A. (Eds.), California
Prehistory: Colonization, Culture, and Complexity. Altamira Press, New York,
NY, pp. 53e62.
Erlandson, J.M., Moss, M.L., Des Lauriers, M.R., 2008. Life on the edge: early maritime cultures of the Pacific Coast of North America. Quaternary Science Reviews
27, 2232e2245.
Erlandson, J.M., Rick, T.C., Braje, T.J., 2009. Fishing up the food web? 12,000 years of
maritime subsistence and adaptive adjustments on California’s Channel Islands.
Pacific Science 63 (4), 711e724.
Erlandson, J.M., Rick, T.C., Braje, T.J., Casperson, M., Culleton, B.J., Fulrost, B.,
Garcia, T., Guthrie, D.A., Jew, N., Kennett, D.J., Moss, M.L., Reeder, L., Skinner, C.,
Watts, J., Willis, L., 2011. Paleoindian seafaring, maritime technologies, and
coastal foraging on California’s Channel Islands. Science 331 (6021), 1181e1885.
Erlandson, J.M., Rick, T.C., Vellanoweth, R.L., Kennett, D.J., 1999. Maritime subsistence at a 9300 year old shell midden on Santa Rosa Island, California. Journal of
Field Archaeology 26 (3), 255e265.
Fedje, D.W., Mathewes, R.W., 2005. Haida Gwaii: Human History and Environment
from the Time of Loon to the Time of the Iron People. UBC Press, Vancouver,
British Columbia.
Fenenga, G.L., 1992. Regional Variability in the Early Prehistory of the American
West. Ph.D. dissertation, University of California, Berkeley.
Feng, X., Reddington, A.L., Faiia, A., Posmentier, E.S., Shu, Y., Xu, S., 2007. The changes
in North American atmospheric circulation patterns indicated by wood cellulose. Geology 35 (2), 163e166.
Firestone, R., West, A., Kennett, J., Becker, L., Bunch, T., Revay, Z., Schultz, P.,
Belgya, T., Kennett, D., Erlandson, J., 2007. Evidence for an extraterrestrial
impact 12,900 years ago that contributed to the megafaunal extinctions and the
Younger Dryas cooling. Proceedings of the National Academy of Sciences 104
(41), 16016e16021.
Fitzgerald, R.T., 2000. Cross Creek: An Early Holocene Millingstone Site. The California State Water Project, Coastal Branch Series Paper No. 12. San Louis Obispo
County Archaeological Society, San Louis Obispo, CA.
Ganeshram, R., Pedersen, T., Calvert, S., Murray, J., 1995. Large changes in oceanic
nutrient inventories from glacial to interglacial periods. Nature 376, 755e758.
Gardner, J., Dean, W., Dartnell, P., 1997. Biogenic sedimentation beneath the California Current system for the past 30 kyr and its paleoceanographic significance. Paleoceanography 12 (2), 207e225.
Gilbert, M.T.P., Jenkins, D.L., Gotherstrom, A., Naveran, N., Sanchez, J.J., Hofreiter, M.,
Thomsen, P.F., Binladen, J., Higham, T.F.G., Yohe, R.M., Parr, R.E., Cummings, L.S.,
Willerslev, E., 2008. DNA from pre-Clovis human coprolites in Oregon, North
America. Science 320 (5877), 786e789.
Glassow, M.A., 1996. Purismeno Chumash Prehistory: Maritime Adaptations along
the Southern California Coast. Harcourt Brace College Publishers, Fort Worth, TX.
Glassow, M.A., Gamble, L.H., Perry, J.E., Russell, G.S., 2007. Prehistory of the northern
California Bight and the adjacent transverse ranges. In: Jones, T.L., Klar, K.L.
(Eds.), California Prehistory: Colonization, Culture, and Complexity. Altamira
Press, New York, NY, pp. 191e214.
Goldfinger, C., Nelson, C.H., Johnson, J.E., 2003. Holocene earthquake records from
the Cascadia Subduction Zone and northern San Andreas Fault based on precise
dating of offshore turbidites. Annual Review of Earth and Planetary Sciences 31,
555e578.
Greenwood, R.S., 1972. 9000 Years of Prehistory at Diablo Canyon, San Luis Obispo
County, California. Coyote Press, Salinas, CA.
Grigg, L.D., Whitlock, C., 1998. Late-glacial vegetation and climate change in western
Oregon. Quaternary Research 49, 287e298.
Grigg, L.D., Whitlock, C., 2002. Patterns and causes of millennial-scale climate
change in the Pacific Northwest during Marine Isotope Stages 2 and 3.
Quaternary Science Reviews 21 (18e19), 2067e2083.
Grigg, L.D., Whitlock, C., Dean, W.E., 2001. Evidence for millennial-scale climate
change during Marine Isotope Stages 2 and 3 at Little Lake, western Oregon,
USA. Quaternary Research 56, 10e22.
Hall, R.A., Davis, L.G., Willis, S.C., Fillmore, M., 2005. Radiocarbon, soil, and artifact
chronologies for an early southern Oregon coastal site. Radiocarbon 47 (3),
383e394.
Hanebuth, T., Stattegger, K., Grootes, P., 2000. Rapid flooding of the Sunda Shelf:
a late-glacial sea-level record. Science 288 (5468), 1033e1035.
Harms, S., Winant, C.D., 1998. Characteristic patterns of the circulation in the Santa
Barbara Channel. Journal of Geophysical Research 103 (C2), 3041e3065.
Hendy, I.L., Kennett, J.P., Roark, E.B., Ingram, B.L., 2002. Apparent synchroneity of
submillennial scale climate events between Greenland and Santa Barbara Basin,
California from 30e10 ka. Quaternary Science Reviews 21 (10), 1167e1184.
Hendy, I.L., Pedersen, T.F., Kennett, J.P., Tada, R., 2004. Intermittent existence of
a southern California upwelling cell during submillennial climate change of the
last 60 kyr. Paleoceanography 19, PA3007.
Heusser, C.J., 1960. Late-Pleistocene Environments of North Pacific North America:
An Elaboration of Late-glacial and Postglacial Climatic, Physiographic, and Biotic
Changes. American Geolographical Society, New York, NY.
Heusser, C.J., 1977. Quaternary palynology of the Pacific slope of Washington.
Quaternary Research 8, 282e306.
Heusser, C.J., 1983. Vegetational history of the northwestern United States,
including Alaska. In: Wright, H.E., Porter, S.C. (Eds.), Late Quaternary
477
Environments of the United States. University of Minnesota Press, Minneapolis,
pp. 239e258.
Heusser, C.J., 1985. Quaternary pollen records from the Pacific Northwest Coast:
Aleutians to the Oregon-California border. In: Bryant, V.M., Holloway, R.G.
(Eds.), Pollen Records of Late-Quaternary North American Sediments. American
Association of Stratigraphic Palynologists, Dallas, TX, pp. 141e165.
Heusser, C.J., Heusser, L.E., Peteet, D.M., 1999. Humptulips revisited: a revised
interpretation of Quaternary vegetation and climate of western Washington,
USA. Palaeogeography, Palaeoclimatology, Palaeoecology 150 (3e4), 191e221.
Heusser, L.E., 1978. Pollen in the Santa Barbara Basin, California: a 12,000 year
record. Geological Society of America Bulletin 89, 673e678.
Heusser, L.E., 1998. Direct correlation of millennial-scale changes in western North
American vegetation and climate with changes in the California Current System
over the Past w60 kyr. Paleoceanography 13, 252e262.
Heusser, L.E., Sirocko, F., 1997. Millennial pulsing of environmental change in
southern California from the past 24 k.y.: a record of Indo-Pacific Enso events?
Geology 25 (3), 243e246.
Huyer, A., 1983. Coastal upwelling in the California Current System. Progress in
Oceanography 12 (3), 259e284.
Inman, D.L., 1983. Application of coastal dynamics to the reconstruction of paleocoastlines in the vicinity of La Jolla, California. In: Masters, P., Flemming, N.
(Eds.), Quaternary Coastlines and Marine Archaeology. Academic Press, New
York, NY, pp. 1e49.
Jertberg, P.M., 1986. The eccentric crescent: summary analysis. Pacific Coast
Archaeological Quarterly 22, 35e64.
Jimenez-Moreno, G., Anderson, R.S., Deprat, S., Grigg, L.D., Grimm, E.C., Heusser, L.E.,
Jacobs, B.F., Lopez-Martinez, C., Whitlock, C.L., Willard, D.A., 2010. Millennialscale variability during the last glacial in vegetation records from North
America. Quaternary Science Reviews 29 (21e22), 2865e2881.
Johnson, D.L., 1972. Landscape Evolution on San Miguel Island, California. Ph.D.
Dissertation, Department of Geography, University of Kansas.
Johnson, J.R., Stafford, T.W., Ajie, H.O., Morris, D., 2002. Arlington Springs revisited.
In: Brown, D.R., Mitchell, K.C., Chaney, H.W. (Eds.), The Fifth California Islands
Symposium. Santa Barbara Museum of Natural History, Santa Barbara, CA, pp.
541e544.
Johnson, J.R., Stafford Jr., T.W., West, G.J., Rockwell, T.K., 2007. Before and after the
Younger Dryas: chronostratigraphic and paleoenvironmental research at
Arlington Springs, Santa Rosa Island, California. American Geophysical Union
Joint Assembly, Acapulco, 22e25 May, 2007. Eos 88 (23). http://www.agu.org/
meetings/sm07/sm07-sessions/sm07_PP42A.html, Joint Assembly Supplement
Abstr. PP 42A-03. Accessed online: 03.17.11.
Jones, T.L., Fitzgerald, R.T., Kennett, D.J., Miksicek, C.H., Fagan, J.L., Sharp, J.,
Erlandson, J.M., 2002. The Cross Creek site (CA-SLO-1797) and its implications
for New World colonization. American Antiquity 67 (2), 213e230.
Jones, T.L., Stevens, N.E., Jones, D.A., Fitzgerald, R.T., Hylkema, M.G., 2007. The
central coast: a midlatitutde milieu. In: Jones, T.L., Klar, K.A. (Eds.), California
Prehistory: Colonization, Culture, and Complexity. Altamira Press, New York,
NY, pp. 125e146.
Jones, T.L., Porcasi, J.F., Erlandson, J.M., Dallas, H.J., Wake, T.A., Schwaderer, R., 2008a.
The protracted Holocene extinction of California’s flightless sea duck (Chendytes
lawi) and its implications for the Pleistocene overkill hypothesis. Proceedings of
the National Academy of Sciences 105 (11), 4105e4108.
Jones, T.L., Porcasi, J.F., Gaeta, J., Codding, B.F., 2008b. The Diablo Canyon fauna:
a coarse-grained record of trans-Holocene foraging from the central California
mainland coast. American Antiquity 73, 289e316.
Justice, N.D., 2002. Stone Age Spear and Arrow Points of California and the Great
Basin. Indiana University Press, Bloomington, IN.
Keigwin, L.D., 2002. Late Pleistocene-Holocene paleoceanography and ventilation of
the Gulf of California. Journal of Oceanography 58 (2), 421e432.
Keigwin, L.D., Jones, G.A., 1990. Deglacial climatic oscillations in the Gulf of California. Paleoceanography 5 (6), 1009e1023.
Kennett, D.J., Kennett, J.P., West, G.J., Erlandson, J.M., Johnson, J.R., Hendy, I.L.,
West, A., Culleton, B.J., Jones, T.L., Stafford, T.W., 2008. Wildfire and abrupt
ecosystem disruption on California’s Northern Channel Islands at the AllerodYounger Dryas boundary (13.0e12.9 ka). Quaternary Science Reviews 27
(27e28), 2530e2545.
Kennett, J.P., Ingram, B.L., 1995. A 20,000 year record of ocean circulation and
climate change from the Santa Barbara Basin. Nature 377, 510e514.
Kienast, S., McKay, J.L., 2001. Sea surfaces temperatures in the subarctic northeast
Pacific reflect millennial-scale climate oscillations during the last 16 kyrs.
Geophysical Research Letters 28 (8), 1563e1566.
Kinlan, B.P., Graham, M.H., Erlandson, J.M., 2005. Late Quaternary changes in the
size and shape of the California Channel Islands: implications for marine
subsidies to terrestrial communities. In: Garcelon, D., Schwemm, C. (Eds.),
Proceedings of the Sixth California Islands Symposium. Institute for Wildlife
Studies, Arcata, CA, pp. 131e142.
Koehler, P.A., Anderson, R.S., 1994. The paleoecology and stratigraphy of Nichols
Meadow, Sierra Nevada National Forest, California, U.S.A. Palaeogeography,
Palaeoclimatology, Palaeoecology 112, 1e17.
Koerper, H.C., 1981. Prehistoric Subsistence and Settlement in the Newport Bay Area
and Environs, Orange County, California. PhD dissertation, University of California, Riverside. UMI, Ann Arbor.
Koerper, H.C., Farmer, M.F., 1987. A bear-shaped crescentic from nothern San Diego
County, California. Journal of California and Great Basin Anthropology 9 (2),
282e288.
478
Koerper, H.C., Langenwalter II, P.E., Schroth, A., 1991. Early Holocene adaptations and
the transition phase problem: evidence from the Allan O. Kelly site, Agua
Hedionda Lagoon. In: Erlandson, J.M., Colten, R.H. (Eds.), Hunter-gatherers of
Early Holocene Coastal California. University of California Institute of Archaeology, Los Angeles, CA, pp. 43e62.
Lambeck, K., Yokoyama, Y., Purcell, T., 2002. Into and out of the Last Glacial
Maximum: sea-level change during Oxygen Isotope Stages 3 and 2. Quaternary
Science Reviews 21, 343e360.
Laylander, D., Moore, J.D. (Eds.), 2006. The Prehistory of Baja California: Advances in
the Archaeology of the Forgotten Peninsula. University Press of Florida,
Gainesville, FL.
Leopold, E.B., Nickmann, R.J., Hedges, J.I., Ertel, J.R., 1982. Pollen and lignin records of
late Quaternary vegetation, Lake Washington. Science 218, 1305e1307.
Lyle, M., Koizumi, I., Delaney, M.L., Barron, J.A., 2000. Sedimentary record of the
California Current system, Middle Miocene to Holocene: a synthesis of leg 167
results. In: Lyle, M., Koizumi, I., Richter, C., Moore, T.C. (Eds.), Proceedings of the
Ocean Drilling Program, Scientific Results.
Lynn, R.J., Simpson, J.J., 1987. The California Current system: the seasonal variability
of its physical characteristics. Journal of Geophysical Research 92 (C12),
12947e12966.
Marchesiello, P., McWilliams, J.C., Shchepetkin, A., 2003. Equilibrium structure and
dynamics of the California Current system. Journal of Physical Oceanography
33, 753e783.
Masters, P., Aiello, I.W., 2007. Postglacial evolution of coastal environments. In:
Jones, T.L., Klar, K.A. (Eds.), California Prehistory: Colonization, Culture, and
Complexity. Altamira, New York, NY, pp. 35e52.
Menounos, B., Osborn, G., Clague, J.J., Luckman, B.H., 2009. Latest Pleistocene and
Holocene glacier fluctuations in western Canada. Quaternary Science Reviews
28, 2049e2074.
Minnich, R.A., 2007. Climate, paleoclimate, and paleovegetation. In: Barbour, M.G.,
Keeler-Wolf, T., Schoenherr, A.A. (Eds.), Terrestrial Vegetation of California.
University of California Press, Berkeley, CA, pp. 43e70.
Mix, A.C., Lund, D.C., Pisias, N.G., Boden, P., Bornmalm, L., Lyle, M., Pike, J., 1999.
Rapid climate oscillations in the northeast Pacific during the last deglaciation
reflect northern and southern hemisphere sources. In: Clark, P.U., Webb, R.S.,
Keigwin, L.D. (Eds.), Mechanisms of Global Climate Change. American
Geophysical Union, Washington, D.C, pp. 127e146.
Mohr, A.D., Fenenga, G.L., 2010. Chipped crescentic stones in California. In:
Fenenga, G.L., Hopkins, J.N. (Eds.), A Riddle Wrapped in a Mystery Inside an
Enigma: Three Studies of Chipped Stone Crescents from California. Coyote
Press, Salinas, CA.
Mohr, J.A., Whitlock, C., Skinner, C.N., 2000. Postglacial vegetation and fire history,
eastern Klamath Mountains, California, USA. The Holocene 10 (5), 587e601.
Moss, M.L., Erlandson, J.M., 1995. Reflections on North American Pacific Coast
prehistory. Journal of World Prehistory 9 (1), 1e45.
Moss, M.L., Erlandson, J.M., 1998. Early Holocene adaptations on the southern Northwest Coast. Journal of California and Great Basin Anthropology 21 (1), 13e25.
Nederbragt, A., Thurow, J., Bown, P., 2008. Paleoproductivity, ventilation, and
organic carbon burial in the Santa Barbara Basin (ODP Site 893, off California)
since the last glacial. Paleoceanography 23 (1), PA1211.
Orr, P.C., 1962a. The Arlington Springs site, Santa Rosa Island, California. American
Antiquity 27 (3), 417e419.
Orr, P.C., 1962b. Arlington Springs Man. Science 135 (3499), 219.
Orr, P.C., 1968. Prehistory of Santa Rosa Island. Santa Barbara Museum of Natural
History, Santa Barbara, CA.
Ortiz, J., Mix, A., Hostetler, S., Kashgarian, M., 1997. The California Current of the Last
Glacial Maximum: reconstruction at 42 N based on multiple proxies. Paleoceanography 12 (2), 191e205.
Ortiz, J.D., O’Connell, S.B., DelViscio, J., Dean, W., Carriquiry, J.D., Marchitto, T.,
Zheng, Y., van Geen, A., 2004. Enhanced marine productivity off western North
America during warm climate intervals of the past 52 k.y. Geology 32 (6),
521e524.
Pisias, N.G., Mix, A.C., Heusser, L., 2001. Millennial scale climate variability of the
northeast Pacific Ocean and of the northwest North America based on radiolaria
and pollen. Quaternary Science Reviews 20, 1561e1576.
Porter, S.C., Swanson, T.W., 1998. Radiocarbon age constraints on rates of advance
and retreat of the Puget Lobe of the Cordilleran Ice Sheet during the last
glaciation. Quaternary Research 50, 205e213.
Pride, C., Thunell, R., Sigman, D., Keigwin, L., Altabet, M., Tappa, E., 1999. Nitrogen
isotopic variations in the Gulf of California since the last deglaciation: response
to global climate change. Paleoceanography 14 (3), 397e409.
Punke, M.L., Davis, L.G., 2006. Problems and prospects in the preservation of
late Pleistocene cultural sites in southern Oregon coastal river valleys:
implications for evaluating coastal migration routes. Geoarchaeology 21 (4),
333e350.
Rhode, D., 2002. Early Holocene juniper woodland and chaparral taxa in the central
Baja California Peninsula, Mexico. Quaternary Research 57 (1), 102e108.
Rick, T.C., 2008. An Arena point and crescent from Santa Rosa Island, California.
Current Research in the Pleistocene 25, 140e142.
Rick, T.C., Erlandson, J.M. Kelp forests, coastal migrations, and the Younger Dryas:
late Pleistocene and earliest Holocene human settlement, subsistence, and
ecology on California’s Channel Islands. In: Eren, M.I. (Ed.), The Archaeology of
the Younger Dryas: Case Studies from Around the World. Left Coast Press,
Walnut Creek, CA, in press.
Rick, T.C., Erlandson, J.M., Vellanoweth, R.L., 2001. Paleocoastal marine fishing on
the Pacific Coast of the Americas: perspectives from Daisy Cave, California.
American Antiquity 66 (4), 595e613.
Rondeau, M.F., Cassidy, J., Jones, T.L., 2007. Colonization technologies: fluted
projectile points and the San Clemente Island woodworking/microblade
complex. In: Jones, T.L., Klar, K.L. (Eds.), California Prehistory: Colonization,
Culture, and Complexity. Altamira Press, New York, NY, pp. 63e70.
Rozaire, C., 1978. A Report of the Archaeological Investigations of Three California
Channel Islands: Santa Barbara, Anacapa, and San Miguel. Report on File at the
Central Coast Archaeological Information Center. University of California, Santa
Barbara, Santa Barabra, CA.
Rypins, S., Reneau, S., Byrne, R., Montgomery, D., 1989. Palynologic and geomorphic
evidence for environmental change during the PleistoceneeHolocene transition
at Point Reyes Peninsula, central coastal California. Quaternary Research 32,
73e87.
Sabin, A.L., Pisias, N.G., 1996. Sea surface temperature changes in the northeastern
Pacific Ocean during the past 20,000 years and their relationship to climate in
northwestern North America. Quaternary Research 46, 48e61.
Sancetta, C., 1995. Diatoms in the Gulf of California: seasonal flux patterns and the
sediment record for the last 15,000 years. Paleoceanography 10 (1), 67e84.
Sancetta, C., Lyell, M., Heusser, L., Zahn, R., Bradbury, J.P., 1992. Late-glacial to
Holocene changes in winds, upwelling, and seasonal production of the northern
California current system. Quaternary Research 28, 359e370.
Sea, D.S., Whitlock, C., 1995. Postglacial vegetation history of the high Cascade
Range, central Oregon. Quaternary Research 43, 370e381.
Seki, O., Ishiwatari, R., Matsumoto, K., 2002. Millennial climate oscillations in NE
Pacific surface waters over the last 82 kyr: new evidence from alkenones.
Geophysical Research Letters 29 (23), 2144.
Smith, B.P., 2008. Prehistoric crescentic tools from the Great Basin and California:
a spatial and temporal analysis. Masters thesis, Department of Anthropology,
University of Nevada, Reno Reno.
Smith, S.J., Anderson, R.S., 1992. Late Wisconsin paleoecologic record from Swamp
Lake, Yosemite National Park, California. Quaternary Research 38, 91e102.
Stott, L., Poulsen, C., Lund, S., 2002. Super ENSO and global climate oscillations at
millenial time scales. Science 297, 222e226.
Tadlock, W.L., 1966. Certain crescentic stone objects as a time marker in the western
United States. American Antiquity 31 (5), 662e675.
Thackray, G.D., 2001. Extensive early and middle Wisconsin glaciation on the western
Olympic Peninsula, Washington, and the variability of Pacific moisture delivery to
the northwestern United States. Quaternary Research 55 (3), 257e270.
Thackray, G.D., 2008. Varied climatic and topographic influences on Late Pleistocene mountain glaciation in the western United States. Journal of Quaternary
Science 23 (6e7), 671e681.
Thornburg, J.D., 2006. The Younger Dryas transition observed in lacustrine sediments from Castor Lake, Washington. Senior thesis, Department of Geosciences,
The Pennsylvania State University,
Vacco, D.A., Clark, P.U., Mix, A.C., Cheng, H., Edwards, R.L., 2005. A speleothem
record of Younger Dryas cooling, Klamath Mountains, Oregon, USA. Quaternary
Research 64, 249e256.
Van Geen, A., Zheng, Y., Bernhard, J., Cannariato, K., Carriquiry, J., Dean, W., Eakins, B.,
Ortiz, J., Pike, J., 2003. On the preservation of laminated sediments along the
western margin of North America. Paleoceanography 18 (4), 22.21e22.27.
Walsh, M.K., Whitlock, C., Bartlein, P.J., 2008. A 14,300-year-long record of firevegetation-climate linkages at Battle Ground Lake, southwestern Washington.
Quaternary Research 70, 251e264.
Warren, C.N., 1966. The San Dieguito type site: M.J Rogers 1938 excavation on
the San Dieguito River. In: San Diego Museum Papers, No 5. San Diego, CA, pp.
1e39.
Warren, C.N., 1967. The San Dieguito complex: a review and hypothesis. American
Antiquity 32 (2), 168e185.
West, G.J., 2001. Pollen analysis of late PleistoceneeHolocene sediments from core
CL-73-5, Clear Lake, Lake County, California: a terresetrial record of California’s
cismountain vegetation and climate change inclusive of the Younger Dryas
event. In: West, G.J., Buffaloe, L.D. (Eds.), Proceedings of the Seventeenth Annual
Pacific Climate Workshop. Interagency Ecological Program for the San Francisco
Estuary, Sacramento, CA, pp. 91e106.
West, G.J., Woolfenden, W., Wanket, J.A., Anderson, R.S., 2007. Late Pleistocene and
Holocene environments. In: Jones, T.L., Klar, K.A. (Eds.), California Prehistory:
Colonization, Culture, and Complexity. Altamira Press, New York, NY, pp. 11e34.
Whitlock, C., Bartlein, P.J., 1997. Vegetation and climate change in northwest
America during the past 125 kyr. Nature 388, 57e61.
Whitlock, C., Sarna-Wojcicki, A.M., Bartlein, P.J., Nickmann, R.J., 2000. Environmental history and tephrostratigraphy at Carp Lake, southwestern Columbia
Basin, Washington, USA. Palaeogeography, Palaeoclimatology, Palaeoecology
155 (1e2), 7e29.
Worona, M.A., Whitlock, C., 1995. Late Quaternary vegetation and climate history
near Little Lake, central Coast Range, Oregon. Geological Society of America
Bulletin 107, 867e876.

Younger Dryas environments and human adaptations

Transcription

Similar documents

ASPA Service – New setup

Botallack to Land`s End

coast out coast - Out on the Coast magazine

BENEFACTOR NEWS - Gold Coast Cultural Precinct

Media Kit - WENG 1530 AM

MUSTANG MANIA - Emerald Coast Regional Mustang Club

CARREFOUR LAVAL

TRAVELOGUE - Accent on Tampa Bay Magazine

View PDF - Southworth Development

- West Coast Electric Fleets