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Y-Line Migration – E3b Haplogroup Line (Male)
Your
Y-chromosome results identify you as a member of haplogroup
E3b.
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 M35, the defining marker of haplogroup E3b.
If
you look at the map highlighting your ancestors' route, you will see that
members of haplogroup E3b carry the following
Y-chromosome markers:
M168
> YAP > M96 > M35
Today,
the E3b line of descent is most heavily represented in Mediterranean
populations. Approximately 10 percent of the men in Spain belong to this haplogroup,
as do 12 percent of the men in northern Italy,
and 13 percent of the men in central and southern Italy.
Roughly 20 percent of the men in Sicily
belong to this group. In the Balkans and Greece,
between 20 to 30 percent of the men belong to E3b, as do nearly 75
percent of the men in North Africa. The haplogroup is rarely found in India or East Asia.
Around 10 percent of all European men trace their descent to this line.
For example, in Ireland,
3 to 4 percent of the men belong; in England,
4 to 5 percent; Hungary,
7 percent; and Poland,
8 to 9 percent. Nearly 25 percent of Jewish men belong to this haplogroup.
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/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. Your paternal lineage E3a falls
under one of these ancient branches and is referred to by geneticists as YAP.
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/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. 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.
M35:
Neolithic Farmers
Fast
Facts
Time
of Emergence: 20,000 years ago
Place
of Origin: Middle East
Climate:
Ice Age
Estimated
Number of Homo sapiens: Hundreds of thousands
Tools/Skills:
Upper Paleolithic-Neolithic
The
final common ancestor in your haplogroup, the
man who gave rise to marker M35, was born around 20,000 years ago in the Middle East. His descendants were among the first
farmers and helped spread agriculture from the Middle
East into the Mediterranean region.
At
the end of the last ice age around 10,000 years ago, the climate changed
once again and became more conducive to plant production. This probably helped
spur the Neolithic Revolution, the point at which the human way of living
changed from nomadic hunter-gatherers to settled agriculturists.
The
early farming successes in the Fertile Crescent of the Middle
East beginning around 8,000 years ago spawned population
booms and encouraged migration throughout much of the Mediterranean
world.
Control
over their food supply marks a major turning point for the human species.
Rather than small clans of 30 to 50 people who were highly mobile and
informally organized, agriculture brought the first trappings of
civilization. Occupying a single territory required more complex social
organization, moving from the kinship ties of a small tribe to the more
elaborate relations of a larger community. It spurred trade, writing,
calendars, and pioneered the rise of modern sedentary communities and
cities.
These
ancient farmers, your ancestors, helped bring the Neolithic Revolution
into the Mediterranean.
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.
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