Unit 1: Human Origins and the Agricultural Revolution
Why our species walked out of Africa, how farming appeared independently around the world, and the chain from surplus grain to the first cities.
6 topics · 25 questions
Each topic is a path, not a menu: work down it in order and every question builds on the one above. Click any of them to watch the answer draw itself.
Human Migration Out of Africa
- How it worksShow me the routes early humans likely walked out of Africa and along the coasts of Asia.
- Worked exampleTrace human arrival dates on five continents, from Africa around 300,000 years ago to the Americas around 15,000 years ago.
- Common mistakeWhy doesn't out of Africa mean one tribe walked all the way to Australia in a single lifetime?
- Going furtherWhat changes for a small band of humans the first time they cross into a landscape with no large predators they recognize?
Your turn1 of 2
Modern humans spread from Africa to every inhabited continent on Earth over tens of thousands of years. Why doesn't out of Africa mean one tribe walked all the way to Australia in a single lifetime?Paleolithic Hunter-Gatherer Life
- How it worksWalk me through a day in a Paleolithic band that moves camp every few weeks to follow food.
- How it worksHow did chipping one stone against another turn a rock into a cutting tool?
- Worked exampleFind how many square miles of hunting and foraging territory a band of fifty people needs to feed itself for a year.
- Common mistakeWhy isn't Paleolithic life accurately described as a short, brutal struggle against starvation?
- Going furtherWhat changes about a band's diet and tools once it learns to control fire?
Your turn1 of 2
A Paleolithic hunter-gatherer band of about 52 people needs roughly 13 square miles of hunting and foraging territory per person to feed itself for a year. About how many square miles of territory does the whole band need?The Neolithic Revolution
- How it worksShow me how a warming climate after the last ice age made wild grains worth harvesting.
- How it worksWalk me through how planting the biggest seeds year after year slowly changes a wild grass into wheat.
- Ties togetherHow does the domesticated wheat this topic produces turn directly into the grain surplus that later builds the first cities and states?
Your turn1 of 2
Modern humans survived as foragers for roughly 200,000 years before farming appeared around 10,000 BCE. Why did farming begin when it did, rather than much earlier or later?Domestication of Plants and Animals
- How it worksHow does selecting the calmest, most useful animals generation after generation turn a wolf into a dog?
- Worked exampleTrace wild teosinte's cob growing from a few hard kernels into a modern corn cob over thousands of years of selection.
- Going furtherWhat happens to a wild animal's body and behavior once it spends generations living alongside humans?
- Common mistakeWhy isn't domestication something that happened deliberately in one planned decision?
Your turn1 of 2
Of the huge number of wild plant and animal species on Earth, only a small handful, like wheat, rice, cattle, and dogs, were ever successfully domesticated. Why can only a few be domesticated while almost none of the rest ever are?From Surplus to Cities and States
- How it worksShow me the chain from a farming surplus to full-time specialists to a walled city to a state.
- How it worksHow does storing a grain surplus create both the first granaries and the first tax collectors?
- Common mistakeWhy doesn't a bigger harvest automatically mean a better-fed population?
- Ties togetherHow does the surplus-to-city chain in Mesopotamia repeat itself along the Nile, the Indus, and the Yellow River?
Your turn1 of 2
Early cities had kings, priests, and soldiers who spent their lives ruling, praying, or fighting rather than farming. Why did farming eventually produce roles like these that never grew a single crop?The Invention of Writing
- How it worksWalk me through how clay tokens for counting sheep turn into the wedge-shaped marks of cuneiform.
- How it worksHow do Egyptian hieroglyphs encode sounds and ideas in the same picture-based system?
- Worked exampleFind how many hundred distinct signs a Mesopotamian scribe needed to memorize to read cuneiform, next to the roughly 22 letters of the later Phoenician alphabet.
- Common mistakeWhy isn't early cuneiform writing the same thing as a full alphabet?
- Going furtherWhat changes for a state once its laws and taxes can be written down instead of remembered?
Your turn1 of 2
The earliest known writing systems, like Mesopotamian cuneiform, first appear on clay tablets recording amounts of grain, sheep, and other goods. Why did writing get invented by accountants keeping track of grain, not by poets?