The Origin of Man

The greatest journey ever undertaken left behind a trail of unanswered questions: How did our

species arise and spread around the globe to become the most dominant creature on the planet?

Part of the answer came two decades ago, when scientists stunned the world with the finding,

based on genetic research, that all humans alive today can claim as a common ancestor a woman

who lived in Africa some 150,000 years ago — dubbed, inevitably, “Eve.” But while the notion of an

African origin of the human family has grown to be accepted by most scientists, the details of how

Eve’s ancestors swept out of Africa to populate the rest of the world have remained unclear.

Dr. Albert Chuchward, distinguished scholar, anthropologist, and ar-

cheologist theorizes that the earliest member of the human species ap-

peared about two million years ago in the Great Lakes region of Central

Africa. This early human species eventually spread over the entire conti-

nent. Many individuals in Dr. Churchward’s field generally agree with his

theory, including Dr. L.S.B. Leakey. In 1963, Leakey found primitive hu-

man fossils, 1.2 million years old in East Africa.

The African ancestry of human is now generally accepted as a fact. Dr. Eric Higgs, of Cambridge University has made

a study of the migration of ancient men, and claims that the first man of Europe came to the continent from central

and east Africa about 200,000 years ago. Professor Chester Chard, of the University of Wisconsin, has studied the

routes of early men who left Africa to colonize the rest of the world, and he has concluded that there were four pre-

historic migration routes from Africa to Europe.

Further discussion on this theory was published in Newsweek Magazine,

January 11, 1988, in an article called “The Search for Adam & Eve.” The sub-

ject was about the collection and testing of a global assortment of genes.

A trail of DNA was found that led them to a single woman from whom we

all descended. The evidence indicates that Eve lived in Sub-Saharan Africa,

between 80,000 and 200,000 years ago. These descendants began mi-

grating from their original homeland, inhabiting the whole world.

to colonize the rest of the world.

the earliest member of the

human species appeared

about two million years

ago in the Great Lakes

region of Central Africa.

The route of migration out of Africa was into the Middle East and then to the rest of

Eurasia, the Americas, and Oceania.

In 1988, Christopher B. Stringer and Peter Andrews, of the British Museum of

Natural History confirmed the single-origin theory, that Homo Sapiens had

evolved from an African Homo Erectus group, 200,000 years ago who had

later migrated to Asia and Europe about 100,000 later. Both scientists con-

tend that fossil evidence supports their single-origin theory. They also note

that the oldest modern looking human fossils are only 35,000 years old.

In 1965, the 2.4 million years old human skull remains were found in Kenya. This new date places

the origin of human beings within the period of major climate change, a global cooling, which is al-

ready believed to have caused other mammals to undergo evolutionary change. Geologist, John

Martyn discovered the fossils while working in the Chemeron Beds in Kenya’s Great Rift Valley.

The date of the skulls was determined using a new scientific method called, Agron.

These discoveries help to validate the fact that mankind originated in Africa.

Humans born around the Great Lakes region, so very close to the equator,

would have been very heavily pigmented. Gloger’s Law states that warm-

blooded animals born in such an equatorial region as the Great Lakes and

Kenya will secrete a dark pigment called eumelanin

Professor Leakey was asked if any of these early Afri-

cans reached the New World, and he answered: “It is

inconceivable that man, the most curious and mobile

of all animals, would not have come to America when

the elephants, the tapirs and the deer came from Asia. ...

Man spread out from Africa to Asia to Europe. It is incon-

ceivable that he would stay out of America.”

It is inconceivable that man, the most curious and mobile of all animals, would not

have come to America when the elephants, the tapirs and the deer came from Asia...

Scientists are calling her Eve. But her name evokes too

many wrong images - the weak-willed figure in Genesis,

the milk-skinned beauty in Renaissance art, the volup-

tuary gardener in “Paradise Lost” who was all “softness”

and “meek surrender” and waist-length “gold tresses.”

” The scientists’ Eve - one of the most provocative anthro-

pological theories in a decade - was more likely a dark-

haired, black-skinned woman, roaming a hot savanna in

search of food. She was muscular and strong; she might

have torn animals apart with her hands, although she

probably preferred to use stone tools.

She was not the only woman on earth, nor necessarily the most attractive

or maternal woman. She was simply the most fruitful, if that is measured by

success in propagating a certain set of genes. Hers seem to be in all humans

living today: 5 billion blood relatives. She was, by one rough estimate, your

10,000th-great-grandmother.

The “discovery” of Eve rekindled scientists perhaps the oldest human debate: where did we come

from? They also confirmed a belief that existed long before the Bible. Versions of the Adam-and-

Eve story date back at least 5,000 years and have been told in cultures from the Mediterranean to

the South Pacific to the Americas. The mythmakers spun their tales on the same basic assump-

tion as the scientists: that at some point we all share an ancestor.

The scientists don’t claim to have found the first woman, merely a common

ancestor - possibly one from the time when modern humans arose. What’s

startling about this Eve is that she lived 200,000 years ago. This date not only

upsets fundamentalists, but also challenges many evolutionists’ conviction

that the human family tree began much earlier.

the Bible’s Eve was

calculated to have lived

5,992 years ago.

The most controversial implication is that modern humans didn’t slowly and inexorably evolve in different parts of the

world, as many anthropologists believed. The evolution from archaic to modern Homo sapiens seems to have oc-

curred in only one place, Eve’s family. Then, sometime between 90,000 and 180,000 years ago, a group of her progeny

left their homeland endowed apparently with some special advantage over every tribe of early humans they encoun-

tered. As they fanned out, Eve’s descendants replaced the locals, eventually settling the entire world.

Trained in molecular biology, they looked at an international assortment

of genes and picked up a trail of DNA that led them to a single woman from

whom we are all descended. Most evidence so far indicates that Eve lived in

sub-Saharan Africa,though a few researchers think her home might have

been southern China. Meanwhile, geneticists are trying to trace our genes

back to a scientifically derived Adam, a putative “great father” of us all. As is

often the case, paternity is proving harder to establish: the molecular trail to

Adam involves a different, more elusive sort of DNA.

The evolution from archaic to modern Homo sapiens seems to have occurred in only one place, Eve’s family.

Eve has provoked a scientific controversy bitter even by

the standards of anthropologists, who have few rivals

at scholarly sniping. Their feuds normally begin when

someone’s grand theory of our lineage is contradicted by

the unearthing of a few stones or bones. This time, how-

ever, the argument involves a new breed of anthropolo-

gists who work in air-conditioned American laboratories

instead of dessicated African rift valleys.

“What bothers many of us paleontologists,” said Fred Smith of the University of Tennessee, “is

the perception that this new data from DNA is so precise and scientific and that we paleontolo-

gists are just a bunch of bumbling old fools. But if you listen to the geneticists, you realize they’re

as divided about their genetic data as we are about the bones. We’re not any more bumbling

than they are.” Dispite of their disagreement, they left Chicago convinced they’re closer to es-

tablishing the origin of humanity. To make sense of their bumbling toward Eden, it is best to go

back to one ancient relative accepted by all scientists. That would be the chimpanzee.

This brotherhood was not always obvious in Chicago two months ago, when the Eve hypothesis

was debated by the American Anthropological Association. Geneticists flashed diagrams of DNA,

paleoanthropologists showed slides of skulls and everyone argued with everyone else.

...all human beings, despite differences in external appearance, are really members of a single entity that’s had a very recent origin in one place.

Some “stones-and-bones” anthropologists accept this

view of evolution, but others refuse to accept this ge-

netic evidence. They think our common ancestor lived

much farther in the past, at least a million years ago,

because that was when humans first left Africa and

began spreading out over the world, presumably evolv-

ing separately into the modern races. As the veteran

excavator Richard Leakey declared in 1977: “There is no

single center where modern man was born.”

But now geneticists are inclined to believe otherwise, even if they can’t agree

where the center was. “If it’s correct, and I’d put money on it, this idea is tre-

mendously important,” says Stephen Jay Gould, the Harvard paleontologist

and essayist. “It makes us realize that all human beings, despite differences

in external appearance, are really members of a single entity that’s had a

very recent origin in one place. There is a kind of biological brotherhood that’s

much more profound than we ever realized.”

But more skeletons kept turning up across Europe and Asia. Anthropologists realized that Ne-

anderthal man was one of many brawny, beetle-browed humans who mysteriously disappeared

approximately 34,000 years ago. These early Homo sapiens, incidentally, were not stooped. Nor

did they fit the stereotype of the savage cave man. Their skulls were thicker than ours, however,

their brains were as large. Their fossils show that they cared for the infirm elderly and buried the

dead. It seemed they might be our ancestors after all.

It appeared that ancient humans traced their lineage back to Africa; that was the only place with evidence of humans living more than a million years ago.

But when? Most anthropologists thought it was at least 15 million years ago,

because they had found bones from that era of an apelike creature who

seemed to be ancestral to humans but not apes. Then, geneticists intruded

with contradictory evidence, led in 1967 by Vincent Sarich and Allan Wilson of

the University of California, Berkeley. They drew blood from baboons, chimps

and humans, then looked at the molecular structure of a blood protein that

was thought to change at a slow, steady rate as a species evolved.

Until the molecular biologists were introduced, the role of the chimpanzee in evolution was de-

pendended on the usual evidence: skeletons. Scientists have relied on bones ever since the

1850s, when Darwin published his theory of evolution and some quarriers unearthed a strange

skeleton in Germany’s Neander Valley. Was the stooped apelike figure a remnant of an ancient

race? Leading scientists thought not. One declared it a Mongolian soldier from the Napoleonic

Wars. A prominent anatomist concluded it was a recent “pathological idiot.”

It appeared that ancient humans traced their lineage back to Africa; that was the only place with evidence of humans

living more than a million years ago. Stone tools were invented there about 2 million years ago by an ancestor named

Homo habilis .Before him was Lucy, whose 3 million-year-old skeleton was unearthed in the Ethiopian desert in 1974.

Lucy was three and a half feet tall and walked erect - not ape, not quite human. At some point her hominid ancestors

began evolving away from the forebears of our closest relative, the chimpanzee.

Fossil hunters in Asia more than a half century ago

found the still older bones of Java man and Peking

man, who had smaller brains and even more muscular

bodies. These skeletons dated back as far as 800,000

years. Perhaps they represented evolutionary dead

ends. Or perhaps they, too, were human ancestors,

with their descendants evolving into modern Asians

while the Neanderthals were becoming modern Euro-

peans - a process of racial differentiation that lasted a

million years.

Wilson, who won a MacArthur “genius grant” in 1986, is once again trying to speed up evolution.

The Eve hypothesis, being advanced both by his laboratory and by a group at Emory University,

is moving up the date when the races of humanity diverged - and once again Wilson faces resis-

tance. Some anthropologists aren’t happy to see Neanderthal and Peking man removed from

our lineage, consigned to dead branches of the family tree. Wilson likes to remind the critics of

the last fight. “They’re being dragged slowly along. They’ll eventually come around.”

Traditional anthropologists did not appreciate being told their estimates were off by 8 million or 10 million years. The

geneticists’ calculation was dismissed and ignored for more than a decade, much to Wilson’s displeasure. “He was

called a lunatic for 10 years. He’s still sensitive,” recalls Rebecca Cann, a former colleague at Berkeley who is now at

the University of Hawaii. But eventually the geneticists were vindicated by the bones themselves. As more fossils

turned up, anthropologists realized that the 15 million-year-old bones didn’t belong to a human ancestor and that

chimps and humans did indeed diverge much more recently.

There were major differences between the molecules of chimps and ba-

boons, as expected, since the two species have been evolving separately

for 30 million years. But the difference between humans and chimps was

surprisingly small - so small, the geneticists concluded, that they must

have parted company just 5 million years ago. Other geneticists used dif-

ferent techniques and came up with a figure of 7 million years.

Homo habilis “Handy Man”

Java man, Peking man-speci-

mens of Homo erectus

The discoverers of this skull cel-

ebrated by staying up all night

drinking beer, and they named

her after the Beatles’ song that

kept blaring on the camp’s tape

player, “Lucy in the Sky with

Diamonds.”

Migrations from tropical to temperate areas, or from temperate to tropical areas, have been rare.

The Sahara in northern Africa separated the African from the Mediterranean peoples and pre-

vented Egyptian and other cultures from spreading to the south. The mountains of the Himala-

yas in South Asia cut off the northern approach to the subcontinent of India.

As a consequence of these and similar barriers, certain mountain passes

and land bridges became traditional migratory routes. The Sinai Penin-

sula in northeastern Egypt linked Africa and Asia, the Bosporus region of

northwestern Turkey connected Europe and Arabia, and the broad valley

between the Altai and Tian Shan mountains of Central Asia enabled Central

Asian peoples to sweep westward.

Humans are constantly on the move, packing up and

resettling in different towns, in a neighbouring coun-

try, or on the other side of an ocean. Humans have

migrated for various reasons since their emergence

as a species. Among the natural causes of migration

are prolonged droughts, changes in climate or volcanic

eruptions that render sizeable areas uninhabitable.

People who migrate tend to seek an environment similar to the one they

left, but they are influenced by natural barriers, such as large rivers, seas,

deserts, and mountain ranges. The belts of steppe, forest, and arctic tun-

dra that stretch from central Europe to the Pacific Ocean encouraged east–

west migration of groups situated along their length.

Humans are constantly on the move

Homo is the genus

that includes modern

humans and their close

relatives. Appearance of

Homo coincides with the

first evidence of stone

tools, and thus by defini-

tion with the beginning

of the Lower Paleolithic.

Homo (genus)

No one knows for sure exactly when humans first be-

came humans. Scientists use certain characteristics

found in fossil evidence (generally the shape of the

skull) to differentiate Homo sapiens from earlier spe-

cies in the genus Homo, such as Homo erectus.

Recently, genetic data has also been used to identify early human populations. Since we’re

not quite sure when humans evolved in Homo sapiens, we’re also not really sure exactly how

or when the earliest humans spread across the rest of the world. Paleoanthropologists have

several theories based on the best evidence available.

The prevailing theory is the Out of Africa theory. Pre-

hu man hominids probably developed in Africa and

spread to Europe and parts of Asia. The first Homo

sapiens appeared in Africa roughly 400,000 years ago.

This is strongly supported by genetic and fossil data.

About 100,000 years ago, they moved north out of Africa into the Middle East, eventually pushing

into Europe and Asia. Homo sapiens coexisted with earlier hominids such as Neanderthals. With

their greater intelligence and organization, Homo sapiens out-competed other pre-human spe-

cies for resources, enjoyed greater reproductive success and eventually replaced them.

A competing theory suggests that pre-humans that already spread throu-

ghout Europe and Asia evolved into Homo sapiens. Separate regional

Homo sapiens populations interbred, passing the characteristics of mod-

ern humans through the entire human population. This theory accounts for

some regional differences seen between different human populations.

Effect of Migration

Stimulates further migration through the displacement of

people living in the area.

Reduces the numbers of the migrating group because of

hardship and warfare.

Decimates indigenous populations through warfare with

invaders and through vulnerability to new diseases.

Alters physical characteristics of ethnic groups through

intermarriage.

Changes cultural characteristics through adoption of the

cultural patterns of peoples encountered.

Modifies language.

With their greater intelligence and organization, Homo sapiens outcompeted other pre-human species for resources.

In the short term, weather events can drive a population out of one area. Flooding and severe

storms can cause this. Long-term migration patterns have been shaped by climate change. A

drought that turns a once-fertile area into a desert will drive the population to find a new home.

Changes in sea level can reveal large stretches of coastal land. Massive sections of frozen

ocean that occurred during the most recent ice age gave humans access to parts of the world

they might not otherwise have reached.

You can only pack so many humans into a given space. Improvements in

medical and sanitation technology make the exact limit enormously vari-

able, and often far higher than the food limit mentioned above, but at some

point the population becomes too large for the area. This can lead to out-

breaks of violence or the spread of virulent diseases. A general decline in

living conditions leads some people to move elsewhere.

The most basic population pressure, and the one that likely drove the earliest migrations out

of Africa, is food. An area of land can only support a certain population with the food produced

there. Modern agricultural techniques and technologies can vastly increase food output, but

in the African forests and savannas of 100,000 years ago, humans subsisted by hunting and

gathering. If the population grew too large, there wouldn’t be enough meat or fruit to feed ev-

eryone. A portion of the population could simply move a few miles away to find new hunting

grounds. Humans may only have moved a few dozen miles per generation, but over tens of

thousands of years, this slow but inexorable migration spread humans throughout the world.

What drove those first humans to leave Africa? That’s best explained by ex-

amining the forces that continue to drive humans to migrate even today. A

population of humans living in a given area faces certain pressures. Those

pressures depend on the size of the population, the resources available

and the community’s ability to exploit those resources.

What drove those first humans to leave Africa?

The most basic population pressure, and the one that likely drove the earliest migrations out of Africa, is food.

Diamond’s argument exceeds its limits on another point as well, that of the

“tilting axes.” Throughout the book Diamond argues that the East-West axis

of Eurasia provided an advantage in the dispersal of useful, mainly domesti-

cated, plants and animals. With respect to the lengths of days and the impor-

tance thereof for flowering plants, the argument makes fine sense.

Maize’s spread northward from Mexico was, Diamond

persuasively argues, slowed by the necessity of genetic

adaptation to different day lengths at different latitudes.

Maize could spread much more easily East-West than

it could North-South. But with respect to animals the

argument must be made in more general climatic and

ecological terms, and here it gets weaker.

Eurasia’s East-West axis could not have been much help in the spread of cattle or goats. Its ex-

treme variety of climatic conditions, its high mountains, deserts, and tropical forests posed a con-

siderable challenge for the spread of most animals (and I should think, plants).

From the Gulf Stream-induced equability of western Europe, to the continental climate extremes

of Kazakhstan, to the monsoon rhythms of Korea, temperature and moisture regimes show tre-

mendous variation. A given line of latitude within Eurasia might embrace conditions as diverse as

those of Shanghai, Lhasa, Delhi, Basra, and Marrakesh, all of which are very close to thirty de-

grees north (North Africa counts for most of Diamond’s purposes as part of Eurasia).

Jared Diamod, the author of “Guns, Germs, and Steel ,“ belives that the avail-

ability of potentially domesticable species and a geography conducive to the

easy spread of useful species. As it happened, Eurasia enjoyed an edge in

both departments. It had far more in the way of domesticable species than

any other continent, and its predominantly East-West axis made for easier

and faster diffusion of species. These are interesting thoughts, new to his-

torians, and they go a long way towards explaining the formidability of some

Eurasian societies vis-a-vis those elsewhere.

domesticated, plants and animals.

Beyond this, since North Africa counts as part of Eur-

asia, then Africa deserves an East-West axis like Eur-

asia’s, because it is farther from Dakar to Cape Garda-

fui than it is from the Cape of Good Hope to the Sahara.

And Australia, which does not get an axis on the map,

extends further East-West than North-South. In Aus-

tralia, I should think rainfall isohyets would correspond

better to the migration history of plants and animals

than lines of latitude and longitude. All this, casts some

doubt on the explanatory power of the axis argument.

Indeed, the successful spread of crops and livestock (not to mention the writing, wheels and other

inventions that Diamond mentions in this argument) is surely determined in large part by factors

other than geography, and the role of geography is much more complex than the axes suggest.

The role of other geographical factors I alluded to in reference to Eurasia. But the spread of use-

ful species was usually a conscious act (weeds were different). They could not, of course, flourish

where ecological conditions did not permit, but where they went when was largely a human affair,

determined by trade links, migration routes, and happenstance.

Coffee, an Ethiopian native, eventually made its greatest impact in southern Brazil, not at Ethiopian latitudes within

Africa. Cattle domestication spread from its point of origin (in southwest Asia) to South Africa and Sweden, flourish-

ing in between in circumstances as diverse as Sudan’s and Switzerland’s. Along the East-West axis of Eurasia, cattle

became important in Europe, fundamental in India, yet inconsequential in China. This is not because Chinese envi-

ronmental conditions were inhospitable to cattle, but because Chinese social and economic conditions were. The dif-

fusion of cattle as of AD 1000 was along a North-South axis more than an East-West one, partly because cattle can

cope with both heat and cold, but also because cattle-raising fit in with the ideological, cultural, social, and economic

systems of some societies better than others, regardless of geography.

Human The diffusion of food production was facilitated in Eurasia because its predominantly East-West axis pre-

sented similar climatic, geographic, and disease conditions to migrants and no insuperable barriers. In contrast,

the diffusion in the predominantly N-S axis in the Americans, Africa, and New Guinea/Australia was slowed by the

greater variation in climate, deserts, diseases (e.g., trypanosomes), nonarable lands, jungles (e.g., Panama), etc. It

was Eurasia that had “amber fields of grain and spacious skies”, not the New World. Diffusion rates varied from 0.7

miles/year out of SW Asia to 0.3 mile/year in the eastern US. The lack of adaptation of the domesticates to these

widely ranging climatic and other differences was a major factor in slowing diffusion in the New World.

East-West axis presented similar climatic, geographic, and disease conditions to

migrants and no insuperable barriers.

Pottery, rock art and

animal remains that

suggest pastoralists -

herders who migrated

to new pasture with

their flocks - first

tended sheep and

cattle in southern

Africa around 2,000

years ago.

—Jared diamond

Expansions of crops, livestock, and even people tended to occur more rapidly along east–west axes than along north–south axes.

Distance between cool highlands of Mexico and Andes was 1,200 miles but

separated by low hot tropical region. Thus, no exchange of crops, animals,

wheel. Only maize spread. It took 2,000 years for maize to cross 700 miles of

desert to reach U.S.A. It took another 1000 years for maize to adapt to U.S.A.

climate to be productive. Geographic barriers like mountains and deserts

also slow spread of crops East-West. Agriculture spread from U.S.A. south-

east to southwest slowed by dry Texas and southern great plains. Amber

waves of grain did not stretch from sea to sea in N. America, but did in Eurasia.

It was easier for domestic plants and animals (later,

technology like wheels, writing) to spread East-West in

Eurasia than North- South in Americas.

Some crops (lima beans, common beans, chili peppers)

domesticated independently in both S. America and

Meso America due to slow spread. Most crops in Eur-

asia domesticated only once. Rapid spread preempted

same or similar domestication. Fertile Crescent crops

spread to Egypt, N. Africa, Europe, India and eventu-

ally to China. East-West spread of plants, animals easier

due to same day-length, similar seasonal variations.

By contrast, spread of these crops stopped past Sahara

due to tropical climate, and thus didn’t reach temper-

ate S. Africa until colonists came. Tropical crops spread

West to East in Africa with Bantu culture, but did not

cross to S. Africa due to climate.

Several domesticable plants had large ranges, but domesticated only in one

place. Why not in others? Domestication required settling down, and had to

be worth it with several plants domesticated, not just one.

Fertile Crescent Attributes; mediterranean climate; abundant wild

stands of wheat that needed little change to be domesticated; hunters/

gatherers settled down before living off grain; and high percentage of

self pollinating plants, are the important factors

There are 200,000 species of plants

Only a dozen account for 80% of worlds production:

Wheat, corn, rice, barley, sorghum, soybean, potato,

sweet potato, sugar cane, sugar beet, banana.

All of these domesticated thousands of years ago.

No new plants domesticated in modern times

Domesticated Plants

When the big 5 Eurasian domesticates (Cow, sheep goat, pig, horse) were

introduced into Africa and the Americas they were readily adopted.

All peoples have experience taming wild animals, keeping pets. But not all

tamed animals can be domesticated.

All major animal domestication occurred between 8,500-2,500 B.C. with

almost none since then.

Those of the 148 possible species capable of being domesticated were

domesticated.

Some species like cows, dogs, pigs independently domesticated in differ-

ent parts of the world. These animals were well suited for domestication.

Attempts to domesticate eland, elk, moose, musk ox, zebra, American

Bison are only marginally successful.

Of the 14 large (over 100 lb) successful domesticated

animal species in the world. Of 148 large herbivorous

or omnivorous species in the world, Eurasia had 72;

Africa 51; Americas 24; and Australia had 1.

Domesticated Animals

Mediterranean climate with

diversity of species.

High percentage of annual

plants. 32 of 56 grass species

grow here.

Diversity of species (big ani-

mals) to be domesticated.

Fertile Cresent Advantages

The research confirms the “Out Of Africa” hypothesis that

all modern humans stem from a single group of Homo

sapiens who emigrated from Africa 2,000 generations

ago and spread throughout Eurasia over thousands of

years. These settlers replaced other early humans, rath-

er than interbreeding .

Academics analysed the mitochondrial DNA (mtDNA) and Y chromosome DNA of Aboriginal Aus-

tralians and Melanesians from New Guinea. This data was compared with the various DNA pat-

terns associated with early humans. The research was an international effort, with researchers

from Tartu in Estonia, Oxford, and Stanford in California all contributing key data and expertise.

The results showed that both the Aborigines and Melanesians share the genetic features that

have been linked to the exodus of modern humans from Africa 50,000 years ago.

Some scholars argue that these discrepancies exist either because the early colonists interbred

with the local Homo erectus population, or because there was a subsequent, secondary migra-

tion from Africa. Both explanations would undermine the theory of a single, common origin for

modern-day humans. But in the latest research there was no evidence of a genetic inheritance

from Homo erectus, indicating that the settlers did not mix and that these people therefore share

the same direct ancestry as the other Eurasian peoples.

All modern humans have a common ancestry

Until now, one of the main reasons for doubting the

“Out Of Africa” theory was the existence of inconsistent

evidence in Australia. The skeletal and tool remains

that have been found there are strikingly different from

those elsewhere on the “coastal expressway”– the route

through South Asia taken by the early settlers.

Reserchers have produced new DNA evidence that confirms

the theory that all modern humanshave a common ancestry.

Mt DNA

Mitochondria DNA (Mt DNA)

are normally inherited ex-

clusively, nearly unchanged,

from the mother. The fact

that Mt DNA is maternally

inherited enables researchers

to trace maternal lineage far

back in time.

“There was probably a minor secondary gene flow into Australia while the land

bridge from New Guinea was still open, but once it was submerged the popu-

lation was apparently isolated for thousands of years. The differences in the

archaeological record are probably the result of this, rather than any second-

ary migration or interbreeding.”

Australia’s aboriginal population sprang from the same small groupof colonists, along with their New Guinean neighbours.

Geneticist Dr Peter Forster, who led the research, com-

mented: “Although it’s been speculated that the popula-

tions of Australia and New Guinea came from the same

ancestors, the fossil record differs so significantly it has

been difficult to prove. For the first time, this evidence

gives us a genetic link showing that the Australian Ab-

original and New Guinean populations are descended

directly from the same specific group of people who

emerged from the African migration.”

At the time of the migration, 50,000 years ago, Australia and New Guinea were joined by a land

bridge and the region was also only separated from the main Eurasian land mass by narrow

straits such as Wallace’s Line in Indonesia. The land bridge was submerged about 8,000 years

ago. The new study also explains why the fossil and archaeological record in Australia is so differ-

ent to that found elsewhere even though the genetic record shows no evidence of interbreeding

with Homo erectus, and indicates a single Palaeolithic colonisation event.

The DNA patterns of the Australian and Melanesian

populations show that the population evolved in rela-

tive isolation. The two groups also share certain genetic

characteristics that are not found beyond Melanesia.

This would suggest that there was very little gene flow

into Australia after the original migration.

Dr Toomas Kivisild, from the Cambridge University Department of Biologi-

cal Anthropology, who co-authored the report, commented that, “The evi-

dence points to relative isolation after the initial arrival of the group, which

would mean any significant developments in skeletal form and tool useage

were not influenced by outside sources.

The archaeological data also indicates an intensification of the density

and complexity of different stone tools in Australia during the Holocene

period (beginning around 10,000 years BP), in particular the emergence

of backed-blade stone technology. The first dingos arrived at around the

same time, and it is thought both were brought to the continent by new

human arrivals – leading to theories of a secondary migration that has

resulted in disputes regarding the single point of origin theory.

Homo sapiens originated in Africa 150,000 years ago

and began to migrate 55,000 to 60,000 years ago. It is

thought he arrived in Australia around 45,000 years

before present (BP). Australia was, at the time, already

colonised by homo erectus. The eastern migration route

towards Australia is referred to as the “coastal express”

route, due to the comparatively rapid progress made by

those who used it. This dispersal, from Africa to Austra-

lia through Arabia, Asia and the Malay peninsula, could

have occurred at a rate of 1km per year.

Australia’s archaeological record provides several apparent inconsisten-

cies with the “Out Of Africa” theory. In particular, the earliest known Austra-

lian skeletons, from Lake Mungo, are relatively slender and gracile in form,

whereas younger skeletal finds are much more robust. This robustness,

which remains, for example, in the brow ridge structure of modern Aborigi-

nes, would suggest either interbreeding between homo sapiens and homo

erectus or multiple migrations into Australia, followed by interbreeding.

Related Information

—Spencer WellS

In 1758, Carl Linnaeus, the father of taxonomy, coined

the term Homo Sapie-ns in his book Systema Naturae -

one of the first records of man’s quest for his roots. The

fascination continued throughout the centuries, which

was propelled by Darwin’s theories, technological ad-

vances and increased funding.

In 1963, the concept of races or sub-species within the human race was re-

fined by Carleton Coon in The Origin of Races. And now, gene mapping and

tracing of roots has been elevated to a whole new level, with the Genographic

Project, a five-year research jointly being conducted by National Geographic

Society, IBM Corp. and the Waitt Family Foundation. This path-breaking proj-

ect is unravelling the story of our origins through 100,000 DNA samples.

through reconstructing the family tree

Dr Spencer Wells, the National Geographic Explorer in

Residence and Population Geneticist, who developed

the concept and now provides overall coordination, says,

Genographics is a concerted scientific effort to answer

the basic question where do we all come from?

According to Dr Wells, there are approximately 50 mutations in our genetic structure, which cre-

ate variations in the gene pool of every generation, which in turn gets passed on to the next. DNA

(deoxyribonucleic acid) is a long informational molecule and the sequence of its components pro-

vides information about the origins and evolution of human beings.

We delve into the DNA composition of individuals to arrive at the answer to

this question, by reconstructing the family tree of everyone alive today. Dr

Wells was in town to deliver a lecture on Deep Ancestry Inside the Geno-

graphic Project at the Georgetown University at Education City.

He speaks at great length on the various components

of the project, the partners, the findings so far, the sam-

pling structure, indigenous populations, what the proj-

ect is doing with them, how the project findings will help

humanity at large and the ethical issues involved.

We delve into the DNA composition of individuals

to arrive at the answer to this question, by reconstructing the

family tree of everyone alive today.

The DNA samples are being collected by voluntary public participation. This

unprecedented effort, led by National Geographic which is distributing and

selling the Participation Kits, will map humanity’s genetic journey through

the ages while helping us better understand our own history. The findings

will also help in understanding how, despite our diverse appearances, we all

share common origins and how we went about populating the planet.

The story that we are telling from the findings so far suggest that we, homo

sapiens, originated as a species in Africa some couple of thousands of years

ago. It is a common stock that gave rise to the entire human race. We are all

members of an extended African family and started to leave that place some

time around 60, 000 years ago to populate the entire world which is roughly

2000 generations, a blink of an eye in evolutionary science.

On the detailed structure of the project, Wells adds, the entire model of the

project is based on cooperation between the scientists who are participat-

ing in the project and the tribal elders. The project involves extensive travels

to enable the researchers reach the local indigenous population, explaining

what we are looking at and eliciting their interest in the project and explaining

what is involved in participating.

The route we are taking to collect DNA is through blood samples or cheek swabs. We then extract

the DNA, purify it and then take what is called genetic markers, which are random but tiny little

changes in the DNA that occur in them and are passed on from generation to generation. These

are markers of descent, which then are mapped against the family trees. This is the core of the

project and we have three components.

The first Field Research is what we are doing with indigenous people, which is any group of people who have lived in

one place for the past 500 years or more and have a connection with the place that they have lived. The tenure varies it

could be 500 years for some locations or in others it could extend to 100,000 years in the case of Africa or 50, 000 years

in the case of Southern India or Australia. It could be a tribe, a village, any population combine that has not been af-

fected by the mass migrations all over that were necessitated with the Industrial Revolution. We are studying 100,000

such samples. The field researchers are being led by a group of population geneticists who study genetic variations

and there are 10 regions across the globe where the research is on.

The second is Public Participation and Communication, which is the story of all of us and thus we

wanted to encourage wide public participation, even outside indigenous populations. The partici-

pation of the project helped financing the third component of the project -- the Legacy Project that

will help us in giving something tangible back to these indigenous people. So far we have raised

$2.2 million and this money is being utilised for the educational and cultural initiatives that have

been organized by these indigenous people themselves, like language or crafts preservation.

The human body consists of 60 thousand billion cells (eg white blood cells,

muscle cells, or cheek cells) of which nearly every single cell contains our

entire genetic information, the DNA. Inside the cell, DNA is found inside the

nucleus (chromosomal DNA, consisting of autosomal DNA, X chromosomal

DNA and Y chromosomal DNA) and outside the nucleus (mitochondrial DNA).

Our autosomal DNA is inherited from both parents. Y-

chromosomal DNA (Y-DNA) is inherited only from father

to son, and mitochondrial DNA (mtDNA), from our mother.

In 1987, three scientists announced in the journal Nature that they had found

a common ancestor to us all, a woman who lived in Africa 200,000 years ago.

She was given the name “Eve.” The “Eve” in question was actually the most

recent common ancestor through matrilineal descent of all humans living

today. That is, all people alive today can trace some of their genetic heritage

through their mothers back to this one woman.

The scientists hypothesized this ancient woman’s existence by looking within

the cells of living people and analyzing short loops of genetic code. Scien-

tists have used DNA to trace the evolution and migration of human species,

including when the common ancestor to modern humans lived—though

there has been considerable debate over the validity of the findings.

The scientists hypothesized this ancient woman’s existence by looking

within the cells of living people and analyzing short loops of genetic code.

Human Cell

MtDNA is not contained in the nucleus but is located in

the cytoplasm of the cell. All of the mtDNA in the cells of

a person’s body are copies of his or her mother’s mtDNA.

A son recieves his mtDNA from his mother, but does not

pass it to his offspring.

mitochondria

nucleus

cytoplasm

chromosomes

every single cell contains our entire genetic

information

After the process of fertilization,

the sperms’ mitochondria die away,

and the embryo is only left with

maternal mitochondria. We share

the same mtDNA as our brothers

and sisters, but not our fathers.

The logical extension of this is that we all ultimately trace back to one woman who lived around

150,000 years ago, who is commonly referred to as Mitochondrial Eve. Since that time, Mitochon-

drial Eve’s descendants have gradually populated the entire globe, with the original founder group

spreading geographically and branching genetically in the course of the millennia, leaving genetic

footprints - or mutations in their mtDNA - at regular intervals wherever they went. These prehis-

toric branching events can be read in the ancient mutations of our mtDNA like in a history book.

mtDNA has now been used to trace back through all of

these natural mutations to the origins of all modern hu-

man existence to a woman known poetically as ‘Mito-

chondrial Eve’, who lived around 150,000 years ago.

‘Mitochondrial Eve’ is most recent common ancestor of all humans alive on Earth today with re-

spect to our matrilineal descent. Note that this does not necessarily mean that she was the only

woman alive at that time. Presumably there were other females alive at that time, but her lineage

is the only female lineage to have survived through to the modern day. Since then, as people have

migrated across and out of Africa, their mtDNA has changed slightly owing to very occasional mu-

tations in the genetic structure, offering us the wealth of different mtDNA types now.

The concept of ‘Mitochondrial Eve’ is in some sense a purely mathematical

fact. Consider the number of all women living on earth today, ‘A’. Now consid-

er the number of the mothers of all women living on earth today, ‘B’. Obviously,

B is either the same size or less than A. As you go back through the genera-

tions, B reduces, ultimately to one woman. That woman is popularly referred

to as Mitochondrial Eve.

MtDNA is passed down nearly unchanged from generation to generation. So

we share the same mtDNA-type as our mother, our maternal grandmother,

our maternal great-grandmother and so on. In fact the exact same mtDNA

code will track our direct genetic line back until the point at which a natural

mutation in the mtDNA code occurred - on average about every 10,000 years.

Mitochondrial

...the exact same mtDNA code will track our direct genetic line back until the point at which a natural mutation in the mtDNA code occurred.

Y chromosome is the sex-

determining chromosome males.

Y chromosome is passed down

exclusively from father to son,

all human Y chromosomes

today trace back to a single

prehistoric father,

“Y chromosomal Adam”.

Y chromosome

The y-chromosome is a good candidate for population studies such as this because it doesn’t recombine as other

parts of the genome do (each parent contributes half of a child’s DNA, which join together to form a new genetic com-

bination). Thus, the y-chromosome is passed on as a chunk of DNA from father to son, basically unchanged through

generations except for random mutations.These random mutations, which can happen naturally and be harmless,

are called markers. Once a marker has been identified, geneticists can go back in time and trace it to the point at which

it first occurred, which would be the most recent common ancestor.

In such cases, two Y tests are needed: one Y test for one-

self, and Y test for the person with the same surname

who is suspected to be related. All that is then needed is

to compare whether the two Y results are identical.

Additionally, family researchers (genealogists) who wish to know whether

two people with the same surname are related, are increasingly using Y chro-

mosomal tests. This is possible because in many cultures, family names or

surnames are passed down by the father just like the Y chromosome.

Because the Y chromosome is passed down exclusively

from father to son, all human Y chromosomes today

trace back to a single prehistoric father, “Y chromosomal

Adam”, whose time we can date to more than 100,000

years ago using statistical methods.

Just like mtDNA, the original Y chromosome has mutated its DNA naturally

over the generations and these new Y types have settled in various parts of

the world in prehistory. By determining your present Y-type and searching

the worldwide Y database, Cambridge DNA Services can give you a good idea

where in the world your father’s lineage is generally found today.

Y chromosomal

No historical record exists that tracks the migratory patterns of the earliest humans. Scientists piece together the

story of human migration by examining the tools, art and burial sites they left behind and by tracing genetic patterns.

They accomplish that using the DNA markers by looking at mitochondrial DNA (mtDNA), and Y Chromosome.

The DNA is unchanged through generations except for

random mutations. These random mutations, which can

happen naturally and be harmless, are called markers. Once

a marker has been identified, geneticists can go back in time

and trace it to the point at which it first occurred, which

would be the most recent common ancestor.

With the benefit of genetics, and mitochondrial DNA, we

are now able to look at the footprints that our earliest of

ancestors left. Subtle, natural mutations in mitochon-

drial DNA have enabled scientists to analyse the devel-

opment of the world’s populations.

Soon after the appearance of Mitochondrial Eve around 150,000 years ago,

an early expansion of modern humans populated much of Africa, around

100,000 years ago. The incredible story of the peopling of the world is told

through a combination of genetics and archaeology.

The group of mtDNA sequences from this first expan-

sion can still be found today, particularly in the KhoiSan

of Southern Africa and the West pygmies of Central Afri-

ca. These earliest groups of mtDNA sequences - or hap-

logroups - are known by scientists as ‘L1’ and ‘L0’, and all

subsequent groups are also known by a letter.

About 60,000 years ago a founder group moved out of Africa and their descendants, through the

natural process of mutation, formed the haplogroups M and N. These groups in turn gained a

foothold during the Ice Age in Asia, Australia and parts of Europe and evolved their own specific

types. So, for example, Europe is populated by the haplogroups H, I, J, K, T, U, V, W and X; Asia by A,

B, C, D, E, F, G, M, and Y; the Americas by an Asian branch with A, B, C, D and X ; Papua New Guinea

by P and Q; and Australia by further M and N types.

Haplogroups are major branches on the family tree of Homo Sapiens. These haplogroup branch-

es characterize the early migrations of population groups. As a result, haplogroups are usually

associated with a geographic region. If haplogroups are the branches of the tree then the haplo-

types represent the leaves of the tree. All of the haplotypes that belong to a particular haplogroup

are leaves on the same branch. Both mtDNA and Y-DNA tests provide haplogroup information,

but remember that the haplogroups nomenclature are different for each.

Geneticists have found frag-

ments of DNA in the Khoisan

ethnic group, of which the

Kung San people, sometimes

called the Bushmen of the

Kalahari, are one tribe, that

appear to date back to the

very first human beings.

Haplogroups were assigned letters of the alphabet before the complete analysis was

done which means that the specific letter assignment itself is meaningless.

Genealogist has tracked the routes and timing of migration, Based on a synthesis of the mtDNA and Y chromo-

some evidence with archaeology, climatology and fossil study.

160,000-135,000

Four groups travelled as hunter/ga-therers south to the Cape of Good Hope, south-west to the Ivory Coast, carrying the first generation of mtD-NA gene types ‘L1’

Herto Man

135,000-115,000

125,000 years ago, a group travelled across a green Sahara through the open northern gate, up the Nile to the Levant. 1st EXIT.

Reconstructive Eve

115,000-90,000

The branch that reached the Levant died out approximately 90,000 years ago. A global freeze

- up turned this area and north Africa into an ex-treme desert. This regieon was later reoccupied by Neanderthal Man.

destination settlement discovery

74,000 Mt Toba

Eruption of Mt. Toba, Sumarta, caus-ing a 6 year nuclear winter and in-stant 1000 years ice-age with a dra-matic population crash, to less than 10,000 adults. Volcanic ash from the eruption up to 5m deep covered India & Pakistan

74,000 -65,000

After the devastation of the Indian sub-continent, repopulation took place. Groups crossed by boat from Timor into Australia and also from Borneo into New Guinea. There was intense cold in the Lower Pleni-glacial in the north.

Gates of Grief

Blombos

Kota Tampan

90,000-85,000

85,000 years ago a group crossed the mouth of the Red Sea-the Gates of Grief-prior to travelling along the southern coast of the Arabian Peninsula toward India. All non-Af-rican people are descended from this group.

85,000-75,000

From Sri Lanka they continued along the Indian Ocean coast to western Indonesia, then a landmass attached to Asia. Still following the coast they moved around Borneo to South China.

Haua Fteah

65,000-52,000

Dramatic warming of the climate 52,000 years ago meant groups were finally able to move north up the Fertile Crescent returning to the Levant. From there they moved into Europe via the Bospo-rus from 50,000 years ago.

52,000-45,000

Mini Ice Age. Aurignacian Upper Pa-laeolithic culture moved from Turkey into Bulgaria, Europe. The new style of stone tools moved up the Danube into Hungary then Austria.

45,000-40,000

Groups from the east Asian coast moved west through the centeral Asia steppes towards Northeast Asia. From Pakistan they moved into Centeral Asia, and from Indo-China through Tibet into the Quing-hai Plateau.

40,000-22,000

Centeral Asians moed west towards eastern Europe, North into the Arctic Circle and joined East Asians to start the spread nto north-east Eurasia. This period saw the birth of spectacu-lar works of art, as in the Chauvet cave in Fr-nace.. Ancestors of the Native Americans who crossed the Bering land bridge connecting Siberia to Alaska, either passed through the ice corridor reaching Meadowcroft before the LGM, or took the coastal route.

Chauvet

Colonization

Meadowcroft

Dabous Carving

IndianRock Art

ClovisTaima Taima

Luzia

Monte Verde

Bradshaw Paintings

22,000-19,000

During the last Ice Age, Nothern Europe, Asia and North America were de-populated, with iso-lated surviving groups locked in refuges. In North America the ice Corridor closed and the coastal route froze.

19,000-15,000

The last Glacial Maximum18,000 years ago. In North America, south of the ice, groups con-tinued to develop diversity in language, culture and genes as they crosses into South America. Austrailian rock art-Bradshow Paintings

15,000-10,000

Continued amelioration of the global climate. Coastal route recommenced. Monte Verde, Chile-human habitation; radio-carbon dat-ing from 11,790 to 13,565 yeasr ago. Stone tools such as flakes and cobbles were ex-cavated. Recoccupatio n of North America 12,500 years ago from south of the ice going north. In the sub-Arc tic 11,500 years ago people moved out from the Beringean refuge to become the Eskimo, Aleuts and Na-Dene speakers.

10,000-80,000

The final collapse of the Ice Age her-alded the dawn of agriculture. The Sahara was grassland, as implied by the life-size giraffe petroglyphs in Niger. Reconlonisation of Britain and Scandinavia.