Branch: P305
Age: More than 100,000 years old
Location of Origin: Africa
The common direct paternal ancestor of all men alive today was
born in Africa between 300,000 and 150,000 years ago. Dubbed “Y-chromosome
Adam” by the popular press, he was neither the first human male
nor the only man alive in his time. He was, though, the only male
whose Y-chromosome lineage is still around today. All men, including
your direct paternal ancestors, trace their ancestry to one of this
man’s descendants. The oldest Y-chromosome lineages in existence,
belonging to the A00 branch of the tree, are found only in African
populations.
Around 100,000 years ago the mutation named P305 occurred in
the Y chromosome of a man in Africa. This is one of the oldest known
mutations that is not shared by all men. Therefore, it marks one of
the early splits in the human Y-chromosome tree, which itself marks
one of the earliest branching points in modern human evolution. The
man who first carried this mutation lived in Africa and is the ancestor
to more than 99.9% of paternal lineages today. In fact, men who do
not carry this mutation are so rare that its importance in human history
was discovered only in the past two years.
As P305-bearing populations migrated around the globe, they
picked up additional markers on their Y chromosomes. Today, there
are no known P305-bearing individuals without these additional markers.
Around 80,000 years ago, the BT branch of the Y-chromosome tree
was born, defined by many genetic markers, including M42. The common
ancestor of most men living today, some of this man’s descendants
would begin the journey out of Africa to the Middle East and India.
Some small groups from this line would eventually reach the Americas,
while other groups would settle in Europe, and some would remain near
their ancestral homeland in Africa.
Individuals from this line whose ancestors stayed in Africa
often practice cultural traditions that resemble those of the distant
past. For example, they often live in traditional hunter-gatherer
societies. These include the Mbuti and Biaka Pygmies of central Africa,
as well as Tanzania’s Hadza.
When humans left Africa, they migrated across the globe in a
web of paths that spread out like the branches of a tree, each limb
of migration identifiable by a marker in our DNA. For male lineages,
the M168 branch was one of the first to leave the African homeland.
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. Scientists put
the most likely date for when he lived at around 70,000 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.
Your nomadic ancestors would have 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 humanlike 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 allowed modern humans to
rapidly migrate to new territories, exploit new resources, and replace
other hominids such as the Neanderthals.
This mutation is one of the oldest thought to have occurred outside
of Africa and therefore marks a pivotal moment in the evolution of
modern humans. Moving along the coastline, members of this lineage
were some of the earliest settlers in Asia, Southeast Asia, and Australia.
But why would man have first ventured out of the familiar African
hunting grounds and into unexplored lands? The first migrants likely
ventured across the Bab-al Mandeb strait, a narrow body of water at
the southern end of the Red Sea, crossing into the Arabian Peninsula
and soon after developing mutation P143—perhaps 60,000 years
ago. These beachcombers would make their way rapidly to India and
Southeast Asia, following the coastline in a gradual march eastward.
By 50,000 years ago, they had reached Australia. These were the ancestors
of some of today’s Australian Aborigines.
It is also likely that a fluctuation in climate may have contributed
to your ancestors’ exodus out of Africa. The African ice age
was characterized by drought rather than by cold. Around 50,000 years
ago, though, the ice sheets of the Northern Hemisphere began to melt,
introducing a short period of warmer temperatures and moister climate
in Africa and the Middle East. 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.
The next male ancestor in your ancestral lineage is the man
who gave rise to M89, a marker found in 90 to 95 percent of all non-Africans.
This man was likely born around 55,000 years ago in Middle East.
While many of the descendants of M89 remained in the Middle
East, others continued to follow the great herds of wild game through
what is now modern-day Iran, then north to the Caucasus and the steppes
of Central Asia. These semiarid, grass-covered plains would eventually
form an ancient “superhighway” stretching from France
to Korea. A smaller group continued moving north from the Middle East
to Anatolia and the Balkans, trading familiar grasslands for forests
and high country.
Branch: M578
Age: About 50,000 Years Old
Location of Origin: Southwest Asia
After settling in Southwest Asia for several millennia, humans
began to expand in various directions, including east and south around
the Indian Ocean, but also north toward Anatolia and the Black and
Caspian Seas. The first man to acquire mutation M578 was among those
that stayed in Southwest Asia before moving on.
Fast-forwarding to about 40,000 years ago, the climate shifted once
again and became colder and more arid. Drought hit Africa and the
Middle East and the grasslands reverted to desert, and 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.
The next male ancestor in your ancestral lineage is the man
who gave rise to P128, a marker found in more than half of all non-Africans
alive today. This man was born around 45,000 years ago in south Central
Asia and was likely part of the second wave of migrants to move east
from Southwest Asia.
Some of the descendants of P128 migrated to the southeast and
northeast, picking up additional markers on their Y chromosomes. This
lineage is the parent of several major branches on the Y-chromosome
tree: O, the most common lineage in East Asia; R, the major European
and Central Asian Y-chromosome lineage; and Q, the major Y-chromosome
lineage in the Americas. These descendant branches went on to settle
the rest of Asia, the Americas, and Europe. Still many others traveled
to Southeast Asia, and some descendants of P128 individuals moved
across the waters south and east and are most commonly seen in Oceanian
and Australian Aboriginal populations.
Branch: M526
Age: About 42,000 Years Old
Location of Origin: South or Southeast Asia
The man who first carried mutation M526 was part of the second
wave of settlers that migrated around the Indian Ocean and settled
in Southeast Asia. This mutation is shared by men from haplogroups
M, N, O, P, Q, R, and S; these are groups common in East Asia, Southeast
Asia, Oceania, and the Americas.
Branch: M45
Age: Around 35,000 Years Ago
Location of Origin: Central Asia or South Asia
This paternal ancestor traveled with groups to the open savannas
between Central and South Asia during the Paleolithic. These big-game
hunters were the parents to two of the most widespread male lineages
in modern populations, one that is responsible for the majority of
pre-Columbian lineages in the Americas (haplogroup Q)—among
others from Asia and Europe—and one that spread farther north
and west into Asia and produced the highest frequency lineages in
European populations (haplogroup R).
Today, members of this lineage who do not belong to a descendant branch
(haplogroups Q or R) are rare, and geneticists have found them most
often in India. These populations include such diverse groups as the
Saora (23 percent), the Bhumij (13 percent), and Muslims from Manipur
(33 percent).
Branch: M207
Age: About 30,000 Years Ago
Location of Origin: Central Asia
M207 was born in Central Asia around 30,000 years ago. His descendants
would go on to settle in Europe, South Asia and the Middle East over
the following 20,000 years. Today, most western European men belong
to one branch—R-M342—that descended from this lineage.
While it appears to have been one of the earliest lineages to settle
in Europe more than 25,000 years ago, more recent population expansions
associated with the post-glacial repopulation of northern Europe after
the end of the last ice age, as well as the spread of agriculture
during the Neolithic, also contributed to its high frequency in Ireland,
the UK, France and Spain.
One descendant lineage—R-L62—is common in Eastern Europe
and India, and was likely spread in part through the migration of
Indo-European steppe nomads over the past 5,000 years.
Branch: P231
Age: 25,000 – 30,000 Years Ago
Location of Origin: Central Asia
The Paleolithic ancestor who founded this lineage lived a nomadic
lifestyle. His descendants include two major descendant branches that
today account for most European men and many others from Central Asia,
West Asia, and South Asia.
Branch: M343
Age: 17,000 – 22,000 Years Ago
Location of Origin: South Asia or West Asia
The first members of this lineage lived as hunter-gatherers
on the open savannas that stretched from Korea to Central Europe.
They took part in the advances in hunting technology that allowed
for population growth and expansions.
When the Earth entered a cooling phase, most from this line
sheltered in refugia to the southeast of Europe and in West Asia.
It was from these refugia that their populations rapidly expanded
when the ice once more receded. Some traveled west across Europe.
Others moved back toward their distant ancestors’ homelands
in Africa, passing through the Levant region. Through these movements
and the population boom triggered by the Neolithic Revolution, this
lineage and its descendant lineages came to dominate Europe.
Today, it has a wide distribution. In Africa, geneticists have found
this lineage in Northern Africa (6 percent) and central Sahel (23
percent). Its frequency in Europe is at times high and at other times
moderate. It represents about 7 percent of Russian male lineages,
about 13 percent of male lineages in the Balkans, about 21 percent
of Eastern European male lineages, 55 to 58 percent of Western European
lineages, and about 43 percent of Central European male lineages.
In Asia, most men of this lineage are found in West Asia (6 percent)
and South Asia (5 percent). However, trace frequencies of around half
a percent from this lineage are present in East Asia.
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