The 60.000 year journey of my nomadic Y-chromosome
- From: atto <dayib78@xxxxxxxxx>
- Date: Tue, 15 Apr 2008 20:28:26 -0700 (PDT)
By Dayib Ahmed Atto
My deep ancestry and the origin of the Somali people.
In this article I am going to share with you the results of my
participation of The Genographic Project, launched in April 2005, a
five-year genetic anthropology study that aims to map historical human
migration patterns by collecting and analyzing DNA samples from
hundreds of thousands of people from around the world.
I chose to do my tracing through the paternal side of my ancestors,
the Y Chromosome, and I did this mostly due to our Somali culture
which traces our tribal lineages along the father's side of the
family.
I find the story being told by my Y chromosome to be interesting, for
one it says that I am a member of group known as haplogroup E, and
traces me back to one mysterious man with a genetic marker called M96.
(Hope a Somali expert will explain this to us a bit more..)
The 60,000 years migration of my ancestors is most fascinating, and I
hope that this will become an eye opener to many and will settle the
debate about the origin of the Somalis people.
This is the story, these are my results from the Genographic project.:
------
Your Y-chromosome results identify you as a member of haplogroup E.
The genetic markers that define your ancestral history reach back
roughly 60,000 years to the first common marker of all non-African
men, M168, and follow your lineage to present day, ending with M96,
the defining marker of haplogroup E, and also with markers M33 (E1),
M75 (E2), M85 (E2b), and P2 (E3). If you look at the map highlighting
your ancestors' route, you will see that membe
rs of Haplogroup E carry the following Y-chromosome markers:
M168 > YAP > M96
You are descended from an ancient African lineage. Today, the YAP
marker is most common in sub-Saharan Africa. Smaller populations of
men carrying the YAP marker can be found in Northern Africa.
What's a haplogroup, and why do geneticists concentrate on the Y-
chromosome in their search for markers? For that matter, what's a
marker?
Each of us carries DNA that is a combination of genes passed from both
our mother and father, giving us traits that range from eye color and
height to athleticism and disease susceptibility. One exception is the
Y-chromosome, which is passed directly from father to son, unchanged,
from generation to generation.
Unchanged, that is unless a mutation--a random, naturally occurring,
usually harmless change--occurs. The mutation, known as a marker, acts
as a beacon; it can be mapped through generations because it will be
passed down from the man in whom it occurred to his sons, their sons,
and every male in his family for thousands of years.
In some instances there may be more than one mutational event that
defines a particular branch on the tree. What this means is that any
of these markers can be used to determine your particular haplogroup,
since every individual who has one of these markers also has the
others.
When geneticists identify such a marker, they try to figure out when
it first occurred, and in which geographic region of the world. Each
marker is essentially the beginning of a new lineage on the family
tree of the human race. Tracking the lineages provides a picture of
how small tribes of modern humans in Africa tens of thousands of years
ago diversified and spread to populate the world.
A haplogroup is defined by a series of markers that are shared by
other men who carry the same random mutations. The markers trace the
path your ancestors took as they moved out of Africa. It's difficult
to know how many men worldwide belong to any particular haplogroup, or
even how many haplogroups there are, because scientists simply don't
have enough data yet.
One of the goals of the five-year Genographic Project is to build a
large enough database of anthropological genetic data to answer some
of these questions. To achieve this, project team members are
traveling to all corners of the world to collect more than 100,000 DNA
samples from indigenous populations. In addition, we encourage you to
contribute your anonymous results to the project database, helping our
geneticists reveal more of the answers to our ancient past.
Keep checking these pages; as more information is received, more may
be learned about your own genetic history.
Your Ancestral Journey: What We Know Now
M168: Your Earliest Ancestor
Fast Facts
Time of Emergence: Roughly 50,000 years ago
Place of Origin: Africa
Climate: Temporary retreat of Ice Age; Africa moves from drought to
warmer temperatures and moister conditions
Estimated Number of Homo sapiens: Approximately 10,000
Tools and Skills: Stone tools; earliest evidence of art and advanced
conceptual skills
Skeletal and archaeological evidence suggest that anatomically modern
humans evolved in Africa around 200,000 years ago, and began moving
out of Africa to colonize the rest of the world around 60,000 years
ago.
The man who gave rise to the first genetic marker in your lineage
probably lived in northeast Africa in the region of the Rift Valley,
perhaps in present-day Ethiopia , Kenya, or Tanzania, some 31,000 to
79,000 years ago. Scientists put the most likely date for when he
lived at around 50,000 years ago. His descendants became the only
lineage to survive outside of Africa, making him the common ancestor
of every non-African man living today.
But why would man have first ventured out of the familiar African
hunting grounds and into unexplored lands? It is likely that a
fluctuation in climate may have provided the impetus for your
ancestors' exodus out of Africa.
The African ice age was characterized by drought rather than by cold.
It was around 50,000 years ago that the ice sheets of northern Europe
began to melt, introducing a period of warmer temperatures and moister
climate in Africa. Parts of the inhospitable Sahara briefly became
habitable. As the drought-ridden desert changed to a savanna, the
animals hunted by your ancestors expanded their range and began moving
through the newly emerging green corridor of grasslands. Your nomadic
ancestors followed the good weather and the animals they hunted,
although the exact route they followed remains to be determined.
In addition to a favorable change in climate, around this same time
there was a great leap forward in modern humans' intellectual
capacity. Many scientists believe that the emergence of language gave
us a huge advantage over other early human species. Improved tools and
weapons, the ability to plan ahead and cooperate with one another, and
an increased capacity to exploit resources in ways we hadn't been able
to earlier, all allowed modern humans to rapidly migrate to new
territories, exploit new resources, and replace other hominids.
YAP: An Ancient Mutation
Fast Facts
Time of Emergence: Roughly 50,000 years ago
Place of Origin: Africa
Climate: Temporary retreat of Ice Age; Africa moves from drought to
warmer temperatures and moister conditions
Estimated Number of Homo sapiens: Approximately 10,000
Tools and Skills: Stone tools; earliest evidence of art and advanced
conceptual skills
Sub-Saharan populations living today are characterized by one of three
distinct Y-chromosome branches on the human tree. YAP occurred around
northeast Africa and is the most common of the three ancient genetic
branches found in sub-Saharan Africa. It is characterized by a
mutational event known as an Alu insertion, a 300-nucleotide fragment
of DNA which, on rare occasion, gets inserted into different parts of
the human genome during cell replication.
A man living around 50,000 years ago, your distant ancestor, acquired
this fragment on his Y-chromosome and passed it on to his descendants.
Over time this lineage split into two distinct groups. One is found
primarily in Africa and the Mediterranean, is defined by marker M96
and is called haplogroup E. The other group, haplogroup D, is found in
Asia and defined by the M174 mutation.
Your genetic lineage lies within the group that remained close to
home, and was carried by men who likely played an integral role in
recent cultural and migratory events within Africa.
M96: Moving Out of Africa
Fast Facts
Time of Emergence: 30,000 to 40,000 years ago
Place of Origin: Africa
Climate: Dry Ice Age
Estimated Number of Homo Sapiens: Tens of thousands
Tools and Skills: Upper Paleolithic
The next man in your ancestral lineage was born around 30,000 to
40,000 years ago in northeast Africa and gave rise to marker M96. The
origins of M96 are unclear; further data may shed light on the precise
origin of this lineage.
What is known is that there were two great waves of migration out of
Africa. The first small groups of people left around 60,000 years ago
and followed a coastal route that eventually reached Australia. The
second exodus occurred beginning around 50,000 years ago, heading
north. The bulk of these travelers were descendants of a man born with
marker M89, a group we'll call the Middle Eastern Clan. While your
ancestors likely moved out of Africa as part of this group, they were
not descended from M89, but rather bore the marker M96. Some 90 to 95
percent of all non-Africans today are descendants of the Middle
Eastern Clan.
You are descended from an ancient African lineage that chose to move
north into the Middle East. Your kinsmen may have accompanied the
Middle Eastern Clan as they followed the great herds of large mammals
north through the grassy plains and savannas of the Sahara gateway.
Alternatively, a group of your ancestors may have undertaken their own
migration at a later date, following the same route previously
traveled by the Middle Eastern Clan peoples.
Beginning about 40,000 years ago, the climate shifted once again and
became colder and more arid. Drought hit Africa and the grasslands
reverted to desert; for the next 20,000 years, the Saharan Gateway was
effectively closed. With the desert impassable, your ancestors had two
options: remain in the Middle East, or move on. Retreat back to the
home continent was not an option.
This is where your genetic trail, as we know it today, ends. However,
be sure to revisit these pages. As additional data are collected and
analyzed, more will be learned about your place in the history of the
men and women who first populated the Earth. We will be updating these
stories throughout the life of the project.
.
- Prev by Date: African Liberation Day 2008
- Next by Date: Bush Administration: The Gang That Could Not Should Straight
- Previous by thread: African Liberation Day 2008
- Next by thread: Bush Administration: The Gang That Could Not Should Straight
- Index(es):
Loading