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- By 14,000 years ago,
- the Ice Age was winding down.
- As the ice melted, oceans rose, and coastlines changed,
- some environmental barriers between populations vanished.
- While elsewhere, new ones appeared.
- Temperatures and rainfall increased dramatically.
- And some areas became so rich in plants and animals,
- that people no longer had to travel in search of food.
- Instead, people settled into more permanent villages based on foraging.
- By planting the seeds from wild grains near their homes,
- they could supplement their food supplies,
- and stay in the same spot year round.
- Perhaps as they became more[UNDETERMINED],
- they had more opportunities for other,
- ahem, pursuits.
- In any case, populations grew
- and pretty soon, growing families in these villages became less suited
- to the nomadic lifestyle.
- In some places, during droughts or harsh winters,
- local wild plants and animals could no longer support everyone.
- Independently and all over the world,
- people began making the same discovery,
- which would change human societies and the natural environment forever.
- They developed
- AGRICULTURE!
- It's not an obvious choice,
- hunter-gatherers can provide
- food for their families, by working only a few days a week.
- Farming, on the other hand,
- is hard work,
- and a full-time job.
- But farming provided more food to feed larger populations consistently
- Villages began relying more and more on their gardens.
- As mutant varieties of wild grains occured,
- these early agriculturists
- chose the crops with larger seeds
- and grain ears that were easier to gather.
- People also domesticated docile, local animals.
- Villages grew, especially in areas with fertile soil,
- and became cities.
- And settled people became
- more detached from the natural world.
- By 6,000 years ago,
- in Mesopotamia, there were cities
- with wealth, power, and a new social order.
- Whoever controlled grain supplies wielded power.
- And some people no longer had to find
- or produce their own food,
- but rather exchange their services for dinner.
- Agricultural societies
- soon became the dominant way of life for people throughout the world.
- World populations exploded,
- creating more laborers to produce more crops,
- to feed more mouths,
- more land had to be cleared for farming.
- Sometimes, whole towns relocated
- when soils couldn't sustain repeated cultivation.
- And each year, people took their livestock
- farther and farther afield to graze.
- Groups who had been separated for thousands of years came in contact
- as they traveled in search of land, labor, and trade goods.
- New means of transportation brought distant cultures in contact.
- New families produced from these contacts blurred genetic distinctions
- within continents,
- and all around the world.
- Migrating farmers encountered hunter-gatherers.
- In sub-Saharan Africa, for example,
- farmers spread east and south from present-day Cameroon around 5,000 years ago.
- Along the way, they met and absorbed
- many of the people whose ancestors had been living there for thousands of years.
- Some hunter-gatherers who lived next to farming communities
- took up farming themselves.
- But others followed game to areas unsuited to agriculture.
- By 1,500 years ago,
- agriculture dominated most of sub-Saharan Africa.
- But the Calahari Desert, too harsh for farming,
- remained a home of hunter-gatherers,
- who kept not only much of their lifestyle,
- but also their unique click languages.
- In most places throughout the world,
- however, agriculture triumphed.
- As the new farmers on each continent
- expanded and absorbed other hunter-gatherer groups.
- Genetic differences within continents began disappearing,
- setting the stage for the most recent chapter in our human story.