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Transcript
Center for Archaeological Studies Internship Report
Justin Rains
Anth. 3376I
Dr. Hadder
The Center for Archaeological Studies, CAS, was originally founded by Texas State
University to conduct archaeological research of the Spring Lake area. Over time it has come to
include the Aquarena springs area and any new prehistoric or historic excavations deemed
necessary as the university itself grows. Although CAS receives some funding from the
university it is a public entity and a state recognized research center. It also receives academic
and research grants from organizations such as the National Science Foundation and the National
Geographic Society. The employees of CAS are classified as state employees and the center
abides by the Texas State Cultural Antiquities Code. Basically, all work done by CAS falls
under this code because they do receive some state funding through the university.
The Center for Archaeological Studies is unique in that it does not fall solely under
academia or CRM. They are open for both options as a means of revenue and research. This
offers a unique opportunity to the employees of CAS to take time and ask questions of some
CRM excavations that they would otherwise be unable to do in a purely cultural resource
management firm. Most CRM firms are privately operated businesses that are on the time scale
of the contractor who hired them. Most of the work done is in a hurried fashion and only
answers broad questions. Reports are written, turned in quickly and specific answers are sought.
CRM firms are expected to get in and get out. Most contractors see CRM and the state of Texas
antiquities codes as a mere nuisance not a necessity. It is thus necessary for CRM firms to be
prompt and try their very best to stay within the allotted time frame of the contractors; lest they
become known as a real nuisance themselves and lose jobs based on that presumption. Within
the world of CRM it normally takes 2-3 months for all the paper work and bureaucratic red-tape
to be processed before a site can begin to be excavated. This fact may add to the animosity
between contractors and CRM firms. The greatest advantage of CAS is that after they take to the
field in a CRM capacity; they can then ask the more specific questions of artifacts and evidence.
They can become more specific in their inquest of sites and develop small theories or answer
personal questions and research for themselves.
At CAS I started off the semester being introduced to the center itself, a brief tour and
introduction to the people that made it all work. The same day I dove into the work at hand. For
the first several weeks I was made familiar with the library of reports and the resources available
within CAS. When I started working with CAS they had just moved to a new building and had
received a donation of books from well-known Texas Archaeologist, Dee Ann Story. Needless
to say unpacking and checking through some 20-25 boxes of reports and books took some time.
Archaeological reports within CAS are separated by counties. There are 254 counties in Texas
and these counties are divided into five different geographic regions. Along with shelving these
reports; I had to check for duplicates already on the shelves and then with Alkek library to see if
they had copies. Any copies that we did not need were sent to Alkek and those that neither
needed were to be placed in a book sale to raise funds for CAS.
After all the report shelving and library work was accomplished; I was introduced into
the sorting of remains from archaeological sites. The site that I have been working with is an
excavation at Aquarena Springs done by Dr. Bousman of Texas State University. The
excavation was done in June of 2006. I am sorting through screenings that were found under
burned rock. The screenings are delineated into three different sizes; ¼ inch, 1/8 inch, and fine
materials. The screenings show evidence of small mammal consumption in the way of burned
and processed faunal remains. Along with the faunal remains are lithic materials from the
production of lithic tools. Aquarena Springs is one of the longest and oldest inhabited areas in
North America. It dates back to the late Pleistocene and early Holocene. Being able to study the
kind of remains that are found in hunter-gatherer campsites of the late Pleistocene epoch is of
great interest to me; as the peopling of the New World is my area of interest. By studying sites
such as this that are contemporary in time with sites in Florida and as far away as Chile in South
America, I can gain a better understanding of routes and depth of time in which peoples
inhabited different areas. By gaining a background in faunal remains and lithic remains of late
hunter-gatherer peoples; I can associate what I have learned with future research. I have learned
the difference between what bleached bone and burned bone are. After the remains and lithic
materials are sorted into different bags; each piece is counted, logged in, and the overall weight
of all sorted materials are weighed. This is so future researchers can come back and find
materials that may answer future archaeological questions. I have also learned the difference
between geologically made rocks with rock that has been “altered by the hand of man.” In the
archaeological world this can give me a hand up in the job field. Having experience in lab work
and understanding what some lab work encompasses with give me a more competitive edge
when searching for a job.
The work that I have had the opportunity to undertake at CAS has been a great learning
experience to me and has helped me to have a better understanding of the process of analyzing
archaeological remains. I understand from an abstract stance how CRM firms function and their
responsibilities here in Texas; while still understanding how the academic research side can
apply and what the benefits are. Having this background will do nothing short of prepare me for
a career in archaeology and give me invaluable insight into the necessity of both CRM and
academic archaeological work while providing me with some applicable, real-world skills.
The Theory and Evidence for Pacific Coast Migration Routes
Abstract
Debates and ideas about when, from where, and by what route humans peopled the
Americas are often theorized within generalized models based on a north to south expansion
process. These generalized models of the peopling of the Americas assume either single or
multi-wave pulses of people entering North America and migrating internally down through
North America or along the Pacific Coast.
Analyzing the pattern and progression of the earliest viable Native American Indian
populations into the Americas can be accomplished by comparing the geographical distributions
of archaeological sites with the earliest known plausible radiometric dates. By comparing the
regional and temporal distributions of the earliest archaeological sites, the directions from which
the earliest viable Native American Indian populations came into the continents and how they
expanded can begin to be understood.
The use of radiocarbon dates as data, the statistical processing methods used, and the
evidence based on DNA will show that early peoples took not only a north to south route from
Beringia but also a coastal route that led to Mexico, Central America and South America. The
results indicate three earliest mean ages. There is great distance between different sites in North
and South America that have been dated to 12,000 RCYBP, slightly later average ages in Alaska
and parts of Canada are found, along with the abrupt occurrence of Fluted and Fishtail Point sites
at the beginning of the Younger Dryas. By analyzing the empirical data along with the
biological data it is evident that there were not only specific times of migration but also a definite
coastal migration that results in contemporary sites in South America and Alaska. These sites
are not those of closely related peoples, but those of different earlier and later culture groups.
Ultimately, the patterns of early archaeological sites in the Americas, their overlapping
distributions in time, and the possibilities of their cultural and biological diversity are no longer
consistent with the “traditional” models of a single northeast Asian colonization event across
Beringia.
Thesis
My objective is to describe and discuss two different models that have been proposed to
explain the peopling of the Americas and evaluate their validity in terms of modern
archaeological research.
Since modern European peoples discovered the continents of the Western Hemisphere;
they have questioned where the native inhabitants came from and in what way they arrived.
Amongst some of the first ideas marked the Native Americans as the lost tribe of Israel or people
from the lost continent of Atlantis. These antiquated ideas soon passed and, as anthropology
came into the main stream, models of migration changed. One idea stood out from the rest, that
of a north to south migration from Asia across Beringia and into the North American continent
around 10,000 years ago. This became the presiding theory. There is a competing theory of a
coastal migration that has developed in more modern times based on new archaeological
evidence. So was it 10,000 years ago across a frozen bridge of land, or perhaps a coastal
skimming by a maritime based people from Eastern Asia and Siberia 20,000 to 35,000 years
ago? Answers to these questions have always leaned toward the Beringia land bridge theory.
The New World covered by glaciers and contemporary sites of the same time.
Source: (www.ucalgary.ca/applied_history/tutor/migrations/)
The Land Bridge theory postulated that the first people arrived in the Americas during the
waning millennia of the last ice age. (12,500-8,500 B.P.) The theory postulated, simply, that
these people were following the migration of large mammals by way of subsistence patterns.
But in the last 15-20 years new genetic and archaeological evidence has challenged this long
held theory, completely turning the sole idea of mass land-bridge migration on its ear. The
genetic evidence is increasingly clear, pushing back the entry of American Indians into the
Americas to around 15-20 thousand years solidly within the Late Pleistocene epoch. Supporting
archaeological evidence has been slower to reveal itself in North and South America. In recent
decades, emerging evidence from sites in Texas, Alaska, and South America have brought the
discussion of different theories back to the fore front of archaeological debate.
One of the most important sites that have recently come to light is the Gault site in central
Texas. Excavated by the Texas Archaeological Research Laboratory at the University of Texas,
Austin; the site lies at of a small stream valley. Gault provided spring waters and quality chert.
Clovis technology is primarily represented at this site along with artifacts of stone, bone and
teeth. These artifacts dated to the late Pleistocene-early Holocene. (12,900-12,550 B.P.) The
Gault site is not the only Clovis site found in the Americas. Although this site is viewed at
present as a predominantly Clovis site; long periods of occupation suggest that Clovis people in
this area were not newcomers. Several other sites have been found along the Balcones
escarpment and the Edwards plateau region of Central Texas. In regards to the Gault site;
excavations that have been made below well-defined Clovis layers show small numbers of
artifacts. Whether or not these are sparse early Clovis representations cannot clearly stand on its’
own validity but with similar findings at Meadowcroft rock shelter in Pennsylvania, Cactus Hill
in Virginia, and Monte Verde in Chile; these findings cannot go ignored. These excavations give
strong archaeological evidence for a late Pleistocene-early Holocene epoch migration of people.
(Adovasio and Pedler 2004:139) Alaska is recognized most commonly as the entrance place for
Native Americans to the New World. This holds as the prominent view of most migration
models. This model indeed is correct but to what extent? In Alaska there are conflicting
interpretations between the various complexes of Nenana, Denali, and the Mesa complex.
However, these different complexes took place during the Younger Dryas climatic event and that
fact adds to the complexity of understanding the different traditions of the time. None of the
aforementioned complexes that have been reliably dated come close to the antiquity of such sites
as Monte Verde in Chile.
Most modern discussion of peopling models starts with discussions about Monte Verde.
It is the most agreed upon site to break the pre-Clovis barrier. Monte Verde has a completely
different cultural tradition than contemporary sites in Alaska. The assemblages from Monte
Verde bear little resemblance to those of Clovis. There are two different culture traditions
recorded at Monte Verde. The dates of these traditions have been dated in radio-carbon years.
The occupations at Monte Verde are being widely accepted by leading archaeological scholars as
the most ancient evidence of human occupation in South America. Although it is hard to
imagine a population of people occupying an area of South America before most of the dated
sites in all of the Americas; it may in fact be true. These dates are not the only ones taken from
Monte Verde. There is another set of dates that correlate to a later occupation also. The more
modern tradition has been dated to 13,000 RCYBP or approximately 15,500 BP. These dates are
more widely accepted and they also prove a pre-Clovis occupation. (Madsen 2004:141) So the
obvious question is: How did people arrive at that location or other sites before Clovis
occupation dates and where did they come from?
The Pacific Coast Migration model is pertaining to the migration of the Native
Americans into North America. This model proposes that people entering the New World, from
Siberia, followed the Pacific coastline; hunter-gatherer-fishers traveling in boats and along the
shoreline and subsisting primarily on marine resources. (Fladmark 1979:57) Along with the
evidence for people being present, archaeologists have found faunal remains along the Pacific
Northwest Coast that would suggest pre-Clovis occupation and a migration of animals before the
last glacial maximum.
Vancouver Island, off the coast of British Columbia, Canada, supported large mammals,
including mammoths, musk-oxen and bison. A mammoth humerus from southern Vancouver
Island has been dated to 17,000 BP, while tusks from the Fraser valley have been dated to 22,000
BP. Parkland terrestrial fauna found in Port Eliza Cave, Vancouver Island, are between 18,000
and 16,000 BP; they document the presence of small animals as well as the presence of animals
up to the size of a mountain goat. (Bever 2006:601) Early postglacial remains from caves on the
island indicate that mountain goats were again present, and finds from southern Vancouver
Island document large bison, including one dated to 11,750 BP. Neither species remains on the
island today. Some species may have survived on the island through the last glacial maximum. If
they did not, then dispersal of species suggest a pathway out of the glacial corridor at that time.
Perhaps such pathways were widespread and could have assisted in supplementing a route for
human dispersal as well. The idea that animals had a route to follow onto the island would
suggest a coastal corridor that would also be available to migrating people.
Knut Fladmark was one of the first to theorize upon the Pacific Coast Migration model.
Fladmark argued against the Ice Free Corridor hypothesis, which proposes people entered North
America through a narrow opening between two glacial ice sheets. (Fladmark 1979:56)
Fladmark believed that at the time of coastal migrations that the glacial corridor would have been
impassable and thus people chose an obvious coastal “skimming” in boats. The idea is that
people traveled along the edge of Beringia in boats until they reached the ice free shores of the
west coast of North America. Once these people reached these ice free areas, they most likely
stuck close to the shore as they migrated down the coast and into Central America and ultimately
South America. The main problem in evaluating Fladmark’s hypothesis has been the lack of sites
that are able to be excavated. With the melting of glaciers sea level rose and with the rising
waters early coastal sites have been swallowed by the ocean. Archaeologists are now left with a
lack of available data, in the form of artifacts that can be used to validate claims of a Pacific
Coastal Model. As scientists we have to turn to other resources to try and evaluate the evidence
for coastal migrations. To do so, archaeologists are turning to DNA sequencing to track peoples,
flora, and fauna samples.
This map shows present day and ancient coastal land formations along with the proposed coastal route.
Source: (www.agiweb.org/geotimes/feb04/feature_Quest.html)
Many archaeologists, at the present, believe there are several parameters that can identify
a person. These parameters are independent from one another and can vary throughout a
person's life based upon individual experiences. The most important parameters are:
1. Religion, "I practice Islam" 2. Political Alignment, "I am a Libertarian" 3. Linguistics, "I
speak Spanish" 4. Ethnic Identification, "I am Scottish" 5. Material Culture, "I wear denim jeans
and a Led Zeppelin T-shirt" 6. Genotype/phenotype/race, "I have dark eyes and olive-tone skin"
The last parameter is the one that some archaeologists are beginning to turn to. As the
ability for scientist to map the human genetic code moves forward, so do other sciences that can
benefit from such knowledge. From the mitochondrial female cells from the skeletal remains of
a person of ancient origin, we can map and trace a lineal history of migration. Through DNA
sequencing of ancient human remains we can gather together a better and more complete
historiography of peoples all over the world.
DNA Proof
Genetic archaeology is an increasingly emerging sub-field of archaeology. Analysis of
DNA from ancient material represents the new frontier in anthropological genetics. (Burgeret al.
2000; Kolman 1999; Paabo 2004) This developing sub-field focuses on the obtaining of
mitochondrial DNA or DNA and being able to determine different aspects of ancient man
including sex. As this field becomes more main stream, we will be given an opportunity to look
into the lives of these ancient peoples. The DNA left behind can be used to help understand
ecology, subsistence and migrations of ancient man. There are quite a lot of issues with finding
quality DNA. Decaying remains need to be in somewhat good conditions to find good residual
DNA, such as frozen, in a cave environment, or even some desert locales. If a body is decaying
in a humid or damp environment then the possibility of finding workable DNA is very slim.
Ideal examples of DNA sources would be the well preserved mummies of Peru or Egypt and the
"Ice Man" from the Swiss Alps. The most problematic issues in DNA studies are the inability to
successfully analyze DNA from many specimens of interest and the contamination of samples
with exogenous DNA. (Mulligan. 2006:365)
In time genetic archaeology will help us all gain greater knowledge about our human
past. As we take leaps and bounds in archaeology, technology provides us with the ability to
learn more about ancient peoples. The ability to tell the difference between population continuity
and a replacement population can be addressed by DNA analysis and investigation. (Mulligan
2006:371) We will be able to offer future generations more knowledge and more easily related
ideas about where we come from. The possibilities for mapping out migration models for the
Americas are seemingly infinite. If enough genetic evidence can be found to relate to modern
Native Americans then we can truly know what tribes, clans, and moieties are related to one
another. We would not have to rely simply upon origin stories, linguistic speech patterns, and
archaeological remnants, archaeologist would be able to tie all their knowledge together and gain
a new knowledge of ancient culture. (Mulligan. 2006:377)
For archaeologist it proves invaluable when trying to map out specific subsistence
patterns or the relation of different culture groups to one another. (Mulligan 2006:365) Analysis
of DNA is most problematic when trying to gain viable samples from antiquated sources. There
are two conditions that must be present to make a good diagnosis: 1. that you have a viable
sample 2. that the sample is not contaminated. The ideal condition for specimens of DNA is
constant cold and arid climates. The optimal condition to find a specimen would be in
permafrost as it is both cold and dry. Most specimens found in tropic climates do not have
samples that can be easily used. Tropic humidity decomposes specimens quite rapidly. When it
comes to human DNA specimens they are particularly susceptible to contamination. Human
contact is required with the sample and poses the overall greatest threat of contamination and so
great care has to be taken to prepare all samples without contamination. Ones best bet at
obtaining a correct study of human DNA is to remove all other human sample from the lab, use a
dedicated laboratory, and the right equipment. DNA sequencing proves to be quite useful in
investigating the migrations of human populations. The sequencing of faunal and floral remnants
also proves useful to reconstruct the diet, domestication, and overall subsistence ecology of
ancient peoples. There are a few considerations to think about when wanting to use DNA
analysis for archaeological research. DNA research is costly, you will be required to have results
verified, and trained geneticists are required for overall success. There are however cheaper and
just as reliable DNA analysis that can be used such as amino acid profiling. To gain knowledge
from DNA sequencing you must know what questions to ask of the DNA. Once you have
isolated what parts of the DNA you want to analyze, genetic human markers, plant pollen,
specific faunal species, you can then work to isolate those parts of the DNA chain to compare
against other samples. For proper research use of DNA results one must take the specific
analyzed DNA marker and compare it against a good sampling of population. From these
multiple samplings you can conclude whether or not people are related and draw upon that
conclusion to a fuller historiography of the sampled and studied peoples.
When studying DNA and trying to find genotypic connections, scientist must use
mitochondrial DNA or mtDNA. This type of DNA can be used to determine pre-contact
populations. (Mulligan 2006:371) MtDNA is only available from a female specimen. By trying
to use these DNA samples one can attempt to map ancient population movements at a smallscale. Trying to map New World populations can be tricky based solely on the frequencies of
mtDNA. Genetic evidence cannot stand alone to make these interpretations. DNA sequence
data and studying the effects of genetic drift over time will enhance studies of ancient population
movements within the New World.
So to address the issues of migration and more directly the Pacific Coast Migration
Model, we must look to the genetic evidence for two different periods of migration that have
been proven by genetic sequencing of modern Native Americans. There is a range of time that
the diffusion of people into the New World has been estimated. These dates would encompass
the last glacial maximum when humans could not move into southern regions of North America,
by way of land, due to the lack of a corridor to do so. So when we look at the DNA evidence;
what do we come up with? Eskimo-Aleuts have been dated, through the use of molecular DNA
sequencing, to have arrived in between 10,000-5,000 RCYBP.(Madsen 2006:187) This fact
shows that there have without a doubt been more than one migration of peoples to the Americas.
The modern American Indians were present long before the migrations of the Eskimo-Aleut
peoples. Now archaeologists ask DNA sequencing to help clear up the migration models and the
diffusion models of the Americas. Based upon the analysis of many DNA studies, archaeologist
have a more complete picture of how these specific markers have been diffused in the Americas.
In the first group of markers studied it clearly shows that all the groups of Native Americans
share common ancient Asian ancestors but that is where the similarities stop. Some of the
groups share a definite DNA marker that seems to line a north to south line of diffusion along the
Pacific Coast with a few irregularities based upon linguistic differences. Within Native
American groups of eastern North America they share a common linguistic binding but do not all
have a common DNA marker. The DNA evidence that can be assessed at this time can possibly
help us map native populations that currently exist and relate them to artifacts and regions where
we find viable DNA.
Alternate Sources of Evidence
When we cannot find viable sources for comparative DNA analysis, we are forced to find
other avenues to conduct research. In reference to the Monte Verde II site, there has been a lot
of excavation done to prove the antiquity. There has also been a lot of research to prove the idea
that the people had followed a coastal route to arrive at Monte Verde. Most recent excavations,
while excavating a hearth, uncovered remains of nine species of marine algae and some stone
tools. (Balter 2008:37) A tool that was found with some seaweed on the working edge dated to
about 14,000 years. (Balter 2008:37) 14,000 years ago, Monte Verde II was about 90 kilometers
inland. This shows a dependence on marine life and knowledge of its benefits. This evidence
also suggests that Monte Verde II was occupied year round and that resources were exploited
from many different habitats including the coast. (Dillehay 2008:785) The people at Monte
Verde must have had used the Pacific Coastal Route Model to have such a strong understanding
of marine resources. Dr. Tom Dillehay stated in “Monte Verde: Seaweed, Food, Medicine, and
the Peopling of South America,” that Monte Verdians chewed algae and seaweed and traveled
far distances to collect specific species of algae. These species were shown to be high in
nutritional value and were probably good medicinal sources also.
Map of the Monte Verde area showing the location of the sea level and coastline at 15,000 to 14,000 cal yr B.P.
and at the present day. Source: Dillehay, Tom D., et al. 2008 Monte Verde: Seaweed, Food, Medicine, and the
Peopling of South America. Science v.32, 784-786
Erlandson proposed a corollary to the coastal migration theory, the Kelp Highway
Hypothesis, arguing that productive kelp forests supporting similar suites of plants and animals
would have existed near the end of the Pleistocene around much of the Pacific Rim from Japan
to Beringia, the Pacific Northwest, and California, as well as the Andean Coast of South
America. (Erlandson 2002:61) When the coastlines of Alaska and the Northwest coast had de-
glaciated, around 16,000 BP, the kelp forest and reef habitats provided an ecologically similar
environment for migrating people to follow. They recognized these areas as food viable and
could easily follow this unobstructed corridor into the New World. (Gruhn 1994:252) Along with
taking advantage of coastal marine resources, Monte Verdeans regularly moved up and down the
Maullin basin to take advantage of resources and to trade with other people of the same region.
If we assume that other Late Pleistocene people operated under similar practices, it implies that
they traveled along coastal routes, they too may have migrated slowly along and exploited river
basin resources. (Dillehay 2008:786)
Summary
The Pacific Coastal Migration hypotheses are understood to be valid arguments based
upon the evidence for DNA within North America and the Monte Verde site biological evidence.
The algae evidence alone can substantiate Tom Dillehay’s hypothesis and research. The
seaweed evidence confirms a pre-Clovis occupation. The DNA evidence shows how some
people moved within the New World and helps us to create a better historiography of aboriginal
people. When studying migration models it is necessary to also relate the migration of the
animal populations. People hunted these animals and would obviously follow their migrations.
The 16,000 year old, faunal, evidence found on Vancouver Island just reinforces Fladmark,
Gruhn, Balter, and Dillehay’s ideas that pre-Clovis coastal migrations occurred. The Pacific
coastal migrations are a fact and further study of these ideas can only serve to further our
understanding of ancient migrating man. The next questions to answer would be the possible
interior routes of coastal populations and further study of the Atlantic Coastal Migration Theory.
Once we have mapped all of the possible routes and have substantial proof; we can have a better
complete idea of when, where, and how ancient man came to the New World.
Bibliography:
Adovasio, J. M., with Jake Page. The First Americans: In Pursuit of Archaeology’s Greatest
Mystery. New York: Random House, 2002.
Balter, Michael. 2008. Ancient Algae Suggest Sea Route for First Americans. Science v 320,
729.
Bever, MR 2006 Too Little, Too Late? The Radiocarbon Chronology of Alaska and the Peopling
of the New World. American Antiquity 71(4):595-620.
Dillehay, Tom D., et al. 2008 Monte Verde: Seaweed, Food, Medicine, and the Peopling of
South America. Science v.32, 784-786
Erlandson, Jon M. Anatomically Modern Humans, Maritime Migrations, and the Peopling of the
New World. In The First Americans: The Pleistocene Colonization of the New World, edited by
N. Jablonski, 2002. Pp. 59-92. Memoirs of the California Academy of Sciences. San Francisco.
Fladmark, K. R. 1979 Routes: Alternate Migration Corridors for Early Man in North America.
American Antiquity v.44, 55-69.
Gruhn, Ruth 1994 The Pacific Coast route of initial entry: An overview. In Method and Theory
for Investigating the Peopling of the Americas. Robson Bonnichsen and D. G. Steele, eds. Pp.
249-256. Corvallis, Oregon: Oregon State University.
Madsen, D.B.
2004 Entering America: Northeast Asia and Beringia Before the Last Glacial Maximum,
University of Utah Press, Salt Lake City, Utah.
Mulligan, Connie J.
2006 Anthropological Applications of Ancient DNA: Problems and Prospects, Society for
American Archaeology, American Antiquity v. 71, 365-380.