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Genealogy is the study and tracing of
family pedigrees. This involves collecting
the names of relatives, both living
and deceased, and establishing the
relationships between them based on
primary, secondary and/or circumstantial
evidence or documentation, thus building
up a cohesive family tree. Genealogy
is sometimes also referred to as family
history, although these terms may
be used distinctly: the former being
the basic study of who is related
to whom; the latter involving more
"fleshing out" of the life
and family histories of the individuals
involved. One way to find the family
lineage is with the use of the genealogical
method. It is a well-established ethnographic
technique. The early ethnographers
developed symbols that covered the
issue of kinship, descent, and marriage.
Studying one's genealogy is important
in terms of social organization, especially
where people live and work with their
kin everyday. It plays a very important
role in understanding the current
social relations and reconstructing
the history. Marriage is also looked
at because it is important in creating
alliances amongst tribes, clans and
villages.
Data sharing among genealogical researchers
has grown to be a major use of the
Internet. Most genealogy software
programs can output information about
persons and their relationships in
GEDCOM format, so it can be shared
with other genealogists by e-mail
and internet forums or converted into
a family web site using online genealogical
tools such as GED2HTML, PhpGedView,
and Phpmyfamily. Many genealogical
software applications also facilitate
the sharing of information on CD-ROMs
and DVDs made on personal computers.
Genetic Analysis
With the discovery that a person's DNA
contains information that has been
passed down relatively unchanged from
our earliest ancestors, analysis of
DNA is just beginning to be used for
genealogical research. There are two
DNA types of particular interest.
One is the mitochondrial DNA which
we all possess and which is passed
down with only minor mutations through
the female line. The other is the
Y-chromosome, present only in males,
which is passed down with only minor
mutations through the male line.
A genealogical DNA test allows for two
individuals to determine with 99.9%
certainty that they are related within
a certain time frame, or with 100%
certainty that they are not related
within a certain time frame. Individual
genetic test results are being collected
in various databases to match people
descended from a relatively recent
common ancestor. These tests are limited
to either the direct male or the direct
female line.
On a much longer time scale, genetic
methods are being used to trace human
migratory patterns and to determine
biogeographical and ethnic origin.
The results can be used to place people
within ancient ancestral groups. In
a related development, non-genetic
mathematical models of ancestry have
been devised to determine the approximate
year when the most recent common ancestor
of all living humans existed.
Haplotype is a person's individual footprint
of all tested genetic markers. Even
the difference of a single genetic
marker delineates a distinct haplotype.
Haplogroups
are defined by genetic mutations or
"markers" found in Y chromosome
and mtDNA testing. These markers link
the members of a haplogroup back to
the marker's first appearance in the
group's most recent common ancestor.
Haplogroups often have a geographic
relation. Mitochondrial DNA or mtDNA
is the genetic material found in the
mitochondria. It is passed from females
to their offspring without recombining,
and thus is an important tool for
geneticists. X and Y Chromosomes which
determine sex. Females have two X
chromosomes while males have one X
and one Y. When chromosomes pair,
the mismatched Y determines male gender.
Because of the mismatch, part of the
Y chromosome does not recombine with
the X during reproduction. The nonrecombining
part of the Y chromosome contains
a sequence of DNA passed intact from
males to their sons through the generations,
giving population geneticists a useful
tool for studying human history. Random
mutations in the DNA sequence which
act as genetic milestones or genetic
markers. Once markers have been identified
they can be traced back in time to
their origin—the most recent common
ancestor of everyone who carries the
marker.
Human Diversity
There is no such thing as race, thanks
to the genetics revolution. The Human
Genome Project (HGP) has determined
unequivocally that there is the same
amount of genetic variation among
individuals within a so called racial
group as there is between individuals
in different racial groups. What that
means is that there is no real genetic
difference between blacks and whites
or between whites and Asians or between
any of the so called races.
Wonder why it's been so hush-hush? I
mean, you would think this would be
big news. Certainly on the order of
Galileo stating that the Earth goes
around the Sun and not vice versa.
But you haven't heard it on CNN or
read it in your local newspaper. It's
more or less kept within the high
brow community as if the common every
day man in the street just couldn't
take it. So you can read about it
in the Atlantic Monthly or New York
Times, but not your home town newspaper.
And some professors on ivory tower
college campuses are scrambling to
prove it isn't so, just like there
some who argue that Darwin was a fruitcake
and evolution a stunt he pulled to
grab the limelight.
But if we are all one race, which race
are we? One answer is the cute one
that we are the "human race".
But buckle your seat belts folks,
because the genetic answer is that
we are all really black. And white
people are pale adaptations of black
people that evolved during the
past 140,000 years.
From whence does this white skin come?
Weren't we all taught that it was
the black people who evolved black
skin and it happened so they would
be protected from getting skin cancer?
Forget it. Scientists have thrown the
whole notion out. Here's how evolution
works. If you don't live long enough
to reproduce, your genes are lost
to the gene pool forever. There being
no high school back when Humans came
into being, females started reproducing
around the age of 13. Skin cancer
develops later in life when the female
has already reproduced and her genes
have entered the world gene pool.
Bye, bye skin cancer theory.
What scientists now believe is that everyone
started out with dark skin in the
first place because it is protective
against absorbing too much Vitamin
D, which is toxic. Too much vitamin
D causes calcium to be pulled from
the intestines and bones and deposited
in soft tissues all over the body,
damaging the kidneys, heart and blood
vessels. Dark skin screens out UV
radiation and your body, which uses
UV to produce Vitamin D, produces
less of it - a real evolutionary advantage
at the lower latitudes where we began.
So where did the 10,000+ shades of paler
brown, beige, pink, white and what
Crayola crayons used to call "flesh"
come from? Archaeological data places
the origin of genetically modern humans
in sub-Saharan Africa approximately
140,000 years ago. Humans then began
migrating out of Africa in successive
waves, starting approximately 100,000
years or 5000 generations ago. Now
that scientists have mapped the human
genome, they are homing in on when
each wave began their outward bound
journey and where they migrated to.
So far they have confirmed that everyone
on the entire planet, even the 1.3
billion Chinese, have a common ancestor
back in Africa.
For example, the first wave appears to
have been a migration to the Middle
East and then eastward and northward
from there. Some geneticists studying
the human genome map believe that
in a later north moving wave, which
occurred about 60,000 years ago, a
mere 50 people inbred together across
successive generations to create all
the people who now occupy Europe (excluding
recent immigrants, of course).
But wait a minute, I have blond hair,
blue eyes and my hair isn't nappy
and I don't have thick lips. So how
can my great, great, etc grandpappy
be a black African? It's all from
lines of genetic
inheritance splitting apart and then
coming together again. Lines of genetic
inheritance, or lineages, split apart
when there is a mutation that is evolutionarily
advantageous, meaning the mutation
makes it more likely for someone to
reproduce greater numbers of offspring
that survive. Someone with a non advantageous
mutation has offspring that are less
likely to survive.
So as humans migrated out of Africa,
why did dark skinned people start
losing the genetics Powerball Lottery
to their paler kin? Lower UV levels
in the sunlight of the more northern
latitudes meant a dark skinned individual's
body could not produce enough Vitamin
D. Insufficient Vitamin D would then
result in a child developing rickets.
A child with rickets would not likely
reproduce either because it would
die before it could or because its
pelvis would be so deformed it could
not pass a child through the birth
canal. Its genes would be lost forever.
So lighter skin, and more absorption
of Vitamin D at higher latitudes would
be an adaptive genetic advantage.
Interestingly, in high latitudes where
some people still retain dark skin,
such as with the Inuit in the Arctic,
the people obtain significant amounts
of Vitamin D from eating fish and
sea mammal
blubber.
Seal blubber aside, what about all the
other features that make us look so
different? Mutations that endure are
often advantageous to specific climates.
For example, the tall thin body of
the Masai warrior dissipates heat
while the short squat body of the
Inuit retains it. Long northern European
noses moisten and warm the air before
it reaches lungs, while in Africa
short noses remain because the air
is already moist and warm. The Asian's
eyelid folds protect their eyes against
dry sandy desert winds and wind driven
snow. In the far north, light sensitive
blue eyes allow people to see better
when it is dark much of the year.
The tightly coiled hair of the African
keeps the hair off his neck so he
remains cooler. All these diverse
physical features promote the promulgation
of different lines of inheritance,
or ethnic lineages.
Countering this splitting apart of ethnic
lineages is the melding through interbreeding
between different ethnic lineages.
If you walk the Silk Road from Persia
to China, across the southern flank
of Asia, you will see a continuum
of physical feature change. You will
not be able to tell where the European
look ends and the Asian begins.
Many mechanisms for melding ethnic lineages
have been at play. The rape part of
the plunder and pillage drill by invaders,
traders passing through with silver
to buy bedtime favors, marriages for
political convenience to form alliances
between not so friendly tribes, and
the boy and girl from neighboring
tribes sneaking out for a little tryst
under the stars, have all contributed
to the
recombining of diverse ethnic lineages.
So what we have instead of the meaningless
terms Caucasian, Negro, Asian, etc,
is a large multiplicity of ethnic
lineages, all of whom descended from
a only a single black race. So don't
forget, next time you fill in the
U.S. Census you should write in the
word Black next
to the question about your race, regardless
of your shade of pale.
Page last updated:
Sunday, January 29, 2006 18:16:34
-0500
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