In Part 5 of our exclusive series we looked at how new discoveries
of American Indian origins cast doubt on the Bering Strait Theory
throughout most of the 20th century yet were either dismissed or
ignored, all while the cracks grew deeper and deeper.
RELATED: Bering
Strait Theory, Pt. 5: The Theory Comes Crashing Down
Archaeological discoveries in South America in the 1980s
led to a revision in the timeline of the Bering Strait Theory, throwing
the whole theory into doubt. But the dogmatic insistence on a single
passageway in a certain time period was also being challenged on
many other fronts.
It is generally presumed that the new science of genetics is
providing support for the Bering Strait Theory, but that is not
necessarily so. The idea that we are all related is a concept well
known among American Indians and therefore the fact that new genetic
studies are detailing these relationships among humans is not surprising.
The question is not so much, are there relationships?
but do these the new details actually shed light on the movements
of populations in the past.
Adding to the confusion surrounding genetic studies is the newness
of the science, which has caused genetics to be heavily influenced
by the archaeologists, and thus already predisposed to the Bering
Strait Theory. More unfortunate has been the use by geneticists
of the pseudo-scientific classifications of American Indians proposed
by the linguist and Clovis First devotee, Joseph Greenberg, classifications
that are now completely discredited, but still used in genetic studies.
These problems and others have led to the regular publishing of
highly contradictory reports, often in the same year. As University
of Wyoming anthropologist Nicole M. Waguespack noted, Genetic
studies are currently plagued by equifinality, as it has become
clear that multiple scenarios of initial colonization and later
population movements can be devised to account for the modern frequencies
of American haplotypes.
The first simple tests for genetic inheritance involved blood
groups, discovered by the Austrian biologist Karl Landsteiner in
1901, who named the three then-known types as A, B, and O. In 1919,
Ludwik and Hanka Hirschfeld, by sampling soldiers, found that different
ethnicities and races had differing frequencies of having one blood
type or another. In 1923, two immunologists from Cornell University,
Olin Diebert and Arthur Coca, collected blood samples of American
Indians, in part to determine the question of the relation
of the American Indian race to the northeastern Asiatic races.
As Margot Lynn Iverson wrote in her book, Blood Types, after they
compared their samples to those taken from Asian peoples,
Coca and Diebert anticipated finding similar blood group
distributions in the Asian and Indian populations, which would further
support the widely held theory that Native Americans had immigrated
to the Americas from northeastern Asia. They were surprised to find
that, to the contrary, the blood group distributions of the East
Asian and American Indian sample groups were quite different.
The American Indians had a very high likelihood of being type O,
whereas it was not common in Asians. About one-third of the Asians
were type B, but this group was almost non-existent among Indians.
In a pattern that would become familiar with genetic studies of American
Indian origins, Iverson noted;
Despite not finding similarities between the American Indian
and Asian populations, the two researchers interpreted their results
as in accordance with the scientific view that Native Americans
had traveled to the Americas from Eastern Asia by arguing that the
blood group data was evidence of the antiquity of the separation
between the two populations, before the mutations causing the A
and B blood groups had occurred.
The study by Coca and Diebert did not break down the Indian
samples by tribe, a serious flaw in any study. Later studies confirmed
that a high percentage of Indians were type O, leading many to conclude
that this was the original Indian blood type. This appeared to lend
credence to the belief that Indians were one genetic unit, in tune
with the perception that the first Indians were a small group of
hunters who wandered into the Americas over the Bering Strait. But
a report in 1933 threw all of that out the window.
Gustave Matson, a bacteriologist at Washington University in
St. Louis, and H.F. Schrader, an Indian Office doctor, did one of
the few studies in which the genetic markers of a single Indian
nation, in this case the Blackfeet (Piegan), were examined. The
report, Unexpected Differences of Blood Groups in American
Indians, found that the vast majority were type A, and indeed,
the more fullblood they were, the more likely they were
to be type A. They then did another study among the Blackfeet of
Canada and found the same result, leading them to conclude that
originally the Blackfeet were all type A. Matson and Schrader argued
that the results showed that Indians were not originally one homogenous
group, and they suggest the necessity for reconsidering the
origin of the American Indian.
As other genetic markers were developed, they too showed little
relationship between American Indians and Asians. The RH blood group
system, discovered in 1939, found that American Indians were unlikely
to have negative RH factors, the opposite of Asians. Similarly in
fingerprint patterns, Indians are more likely to have similar patterns
to Caucasians than Asians. Moreover, as in the case of blood types,
Indian genetic markers could vary considerably depending on the
tribe, dispelling the notion that Indians are one genetic group,
and making any conclusion problematic.
In 1953, James Watson, Francis Crick, Rosalind Franklin, and Maurice
Wilkins cracked the genetic code by discovering the structure of DNA.
Over the next three decades, scientists would work to identify and
place in proper order the thousands of genes that make up DNA strands,
leading to the sequencing of the DNA in the mitochondria,
the small energy battery inside of a cell, in 1981. Like
radiocarbon dating, sequencing DNA revolutionized, and continues to
revolutionize, our understanding of human origins.
In 1991, an international team led by R.H. Ward from the University
of Utah and Svante Pääbo from the University of Munich
examined the Nuu-Chah-Nulth (Nootka) people of Canada. Their paper,
entitled, Extensive Mitochondrial Diversity Within a Single
Amerindian Tribe, created a stir.
Sequencing of a 360-nucleotide segment of the mitochondrial
control region for 63 individuals from an Amerindian tribe, the
Nuu-Chah-Nulth of the Pacific Northwest, revealed the existence
of 28 lineages defined by 26 variable positions. This represents
a substantial level of mitochondrial diversity for a small local
population.
This was unexpected, as it would take a long time for this diversity
to develop. Given the fixed date of the Bering Strait theory, the
authors could only assume that, the magnitude of the sequence
difference between the lineage clusters suggests that their origin
predates the entry of humans into the Americas, a conclusion
that raised even more questions than it answered.
Other, broader studies were encountering similar problems. Because
Mitochondrial DNA is passed only from a mother it avoids the gene
shuffling that can obscure the evolutionary trail. It also mutates
faster than nuclear DNA, allowing researchers to distinguish populations
that recently separated and estimate when that occurred. As geneticists
began to detect these mutations in different populations, they began
to classify them. Although new variations are still being discovered,
the basic outlines began to fall in place by the early 1990s.
Divided into haplogroups these distinctive sequences
were named A to Z in order of their discovery. In very general terms,
haplogroup L is found largely in Africa and is believed to be the
parent sequence of all modern humans. At some point in the deep
past, two groups, M and N, descended from L and, breaking up into
numerous subgroups, expanded all over the world, including the Americas.
From M, the subgroups C and D, and from N, the groups A, B, and
X, are found in American Indians.
These groups are also found in Asia and Europe, and so it was
presumed that the Eurasian populations with these same haplogroups
were the ancestors of Indians. Even though these haplogroups were
the same in both hemispheres, they were not quite identical due
to mutations over time, allowing the geneticists the ability to
estimate when they had separated from each other. And what they
found surprised them.
Investigations by a number of geneticists began to find extremely
deep ages for when the DNA splits occurred. Michael D. Brown from
Emory University estimated that Haplogroup A divided between 27,000
and 57,000 years ago; Antonio Torroni, professor of genetics at
the University of Pavia, Italy, estimated that B split sometime
between 26,000 and 39,000 years ago and that D split 32,000 to 47,000
years ago; Theodore G. Schurr, professor at the University of Pennsylvania,
estimated that C split between 42,000 and 55,000 years ago, and
X split 13,000 to 17,000 years ago. Sandro L. Bonatto from the Catholic
University of Rio Grande do Sul, Brazil, summed up the situation,
these results put the peopling of the Americas clearly in
an early, pre-Clovis time frame.
Like the linguistic evidence, which indicates that American
Indians have been a separate peoples for at least 40,000 years,
the dates for the Bering Strait theory were in the wrong ballpark,
in the words of linguist Johanna Nichols. To make matters more problematic,
the coalescent age, that is the date when the varying
genes had been one and not split, in some American Indian haplogroups
were older that those of some Asian populations, leading to speculation
that migrations may have occurred both back and forth, to and from
Asia.
RELATED: How
Linguists Are Pulling Apart the Bering Strait Theory
But even with this formidable evidence against it, the Bering
Strait Theory would not die. Because it was simply impossible, according
to the belief, for American Indians to have migrated before the
massive ice sheets blocked their path approximately 30,000 years
ago, a new hypothesis was proposed, originally known as the Three
Stage Expansion but now dubbed the Beringian Standstill
Theory.
Resembling more an invention by Rube Goldberg than a scientific
theory, the Standstill hypothesis is a direct result of the genetic
evidence, which undercuts the Bering Strait Theory. In this scenario,
the ancestors of Indians migrated to Beringia, as the
region that surrounds the Bering Strait is called, between 30,000
and 40,000 years ago. They then waited in Beringiaat that
time a vast plain that connected Siberia and Alaskafor about
20,000 years until the ice sheets melted, and then around 15,000
years ago made their way into the Americas in time to get to Monte
Verde 14,800 years ago.
The Indians, while waiting 20,000 years, also had to be in complete
isolation and not genetically mix with other Asian tribes. In this
way, the unique genetic mutations would have the time to develop,
while at the same time keeping the Paleoindians out of the Americas
before 13,000 BC. Geneticists have looked to find a bottleneck
in genetic growth, and founder effects, that is the
loss of genetic diversity that occurs when only a small population
gives rise to a larger one, that might show there was indeed a 20,000-year
wait in Beringia before the expansion into the Americas. This search
has produced a number of genetic studies with conflicting results,
leaving the whole thing unresolved.
Archaeologists had long held that because there is (under their
standards) no archaeological evidence of Indians in the New World
before 15,000 years ago, they were thus not here. Yet it has been
noted that there is absolutely no archaeological evidence of anyone
living in Beringia during the 20,000 years Paleoindians are supposed
to have been there, either. It would appear that different standards
of evidence are required, depending on the point of view.
What makes the dubious nature of the Standstill hypothesis even
more unfortunate is that perspectives that do not conform with the
Bering Strait Theory, if they are not ignored, are treated with
disdain or ridicule. When the late Sioux philosopher Vine Doloria
Jr. published Red Earth, White Lies: Native Americans and the Myth
of Scientific Fact and challenged the Bering Strait theory, the
book was savagely attacked by many scientists as being unscientific
and anti-science. Yet it is the Bering Strait Theory that has historically
been a collection of pseudoscientific mythologies, promoted virulently
by dogmatists, who have largely held back science and discouraged
free expression. In 1916, in discussing the science of archaeology,
the renowned linguist and a firm believer in the deep antiquity
of American Indians, Edward Sapir, offered a thinly veiled criticism.
The method has yielded brilliant results in the study of
prehistoric Europe and western Asia and is doubtless destined to
teach us vastly more than has yet been disclosed to us about the
earlier culture history of the rest of the world. For America, however,
the results, while of distinct value as far as they go, have so
far been rather more meager than might have been expected. Whether
this is due to the nature of the culture history of America itself
or to certain defects in the field methods of investigators, I would
not venture to decide.
That the science of paleoanthropology in America, and thus the
Bering Strait Theory, were born out of assumptions of Western cultural
and genetic superiority is now widely accepted. Anthropologist Michael
L. Blakey argued in his essay, Skull Doctors Revisited: intrinsic
social and political bias in the history of American physical anthropology;
with special reference to the work of Ale Hrdlicka,
that physical anthropology essentially began as a pseudoscience
offering biological justifications for social inequality.
Professional physical anthropology has, from its inception,
been a powerful ideological force. It successfully competed with
Christianity as elucidator of human origins and gave new, naturalistic
meaning to human social relations. In this important ideological
role, scientific knowledge has been subject to systematic and continuous
influences of broad political and economic interest.
Blakey singled out the father of the modern Bering Strait Theory,
Ale Hrdlicka, as among the most influential of these ideological
skull doctors, and the unfortunate impact of his dubious
scientific methods continues to the very day.
One hundred and twenty years ago, paleoanthropologists were
faced with what they believed to be a dilemma, chaos or order. In
the end they chose order, and in doing so they created the dogma
of the Bering Strait Theory. Like most dogmas, it has taken on a
life of its own, far beyond what its creators could have hoped for
or expected. As a theory it continues to grow and mutate, adapting
to new circumstances, for no amount of evidence to the contrary
will make it disappear.
While there are those who may fear that the loss of a dogma
may lead once again to chaos, there are alternatives to chaos or
order. As the geneticist Rebecca Cann argued, rather than
make dogmatic statements we should encourage the open
exploration of this debate and in doing so, maybe we will
find some answers.
RELATED: Bering
Strait Theory, Pt. 1: How Dogma Trumped Science
RELATED: Bering
Strait Theory, Pt. 2: Racism, Eugenics and When Natives Came to
America
RELATED: Bering
Strait Theory, Pt. 3: The Theory Becomes a Religious Crusade
RELATED: Bering
Strait Theory, Pt. 4: The Indisputable Facts in the Artifacts
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