Well, that’s a long story, spanning over 200,000 years of history. But the Museum's visualization team has a short answer for you.
Check out the segment below to find out how humanity got where it is today—that is to say, more or less everywhere—and what the future holds for a global population that could peak at eleven billion people in less than a century.
[American Museum of Natural History logo appears.]
[A globe takes center screen, and a line graph occupies the lower screen. On the graph’s x-axis is a timeline, starting at 100,000 BC. On the y-axis is global population, in millions.]
[ATMOSPHERIC MUSIC FROM WOODEN FLUTES AND HAND DRUMS]
[TEXT: Modern humans evolved in Africa about 300,000 years ago. Around 100,000 years ago, we began migrating across the globe.]
[Yellow shading indicates the migration route of early humans from Africa through the Middle East, across Europe and Asia, over the Bering Strait and down the western coasts of North and South America.]
[TEXT: Our population remained low—probably less than 1 million people.]
[A horizontal line is drawn on the graph, showing population levels hovering around 1 million from 100,000 BC to 10,000 BC, when it suddenly slopes upward.]
[TEXT: With the advent of farming, growth picked up. By AD 1, world population reached approximately 170 million people.]
[The globe morphs into a flat map of the world. Yellow dots on the map indicate where population centers were in AD 1. Each dot represents 1 million people. There are 170 dots, most concentrated in China, India, the Middle East and Europe.]
[MUSIC SHIFTS TO A MORE INTENSE BEAT]
[As the timeline progresses, more and more dots appear on the map, accompanied by clicking sounds.]
[GEIGER-COUNTER-LIKE CLICKING SOUNDS]
[Historic periods and events are indicated on the map and timeline, as they occur.]
[TEXT: Han Dynasty, Roman Empire, Silk Road, Golden Age of India, Peak of Mayan Civilization, Birth of Islam, Smallpox in Japan, Gunpowder invented, Navigational compass, Mongol Empire, Bubonic Plague, Transatlantic Slave Trade, Industrial Revolution, World Wars]
[A slow, steady increase in global population is indicated through dots on the map, and a gradually upwards sloping line on the graph. Only in the 14th century, with Bubonic Plague, does it dip.]
[TEXT: Rare decline in world population.]
[Starting around the Industrial Revolution in the late 18th century, global population increases much more rapidly.]
[TEXT: Modern technology and medicine bring faster growth]
[HIGH-PITCHED CLICKING AS DOTS MULTIPLY]
[On the map and timeline, human population reaches 8 billion people in 2023.]
[SLOWER, CALMER MUSIC]
[The timeline shifts again, now extending from 1950 to 2100.]
[TEXT: Leveling off. At current rates, global population will peak this century.]
[The line graph shows population peaking around 10.3 billion. The post-2023 estimates are labeled as projections.]
[TEXT: Growth is slowing because average fertility rates are falling in nearly every country.]
[Cartoon babies appear on the timeline. Five are stacked on the left-hand side and two on the right-hand.]
[TEXT: 1950: Five babies per woman. 2100: Two babies per woman.]
[Additional growth trend lines are drawn on. One-and-a-half babies per woman in 2100 defines a lower projection. Two-and-a-half babies per woman in 2100 defines a higher projection.]
[TEXT: If fertility forecasts are slightly off, our population will peak higher…or lower.]
[The timeline morphs again, showing all of human history, from 300,000 BC to today.]
[TEXT: It took most of human history for our population to reach 1 billion. And just over 200 years to reach 8 billion.]
[A line is drawn on, showing a long period of very slow growth, and a short period of very rapid growth. The shape of the curve is like a backwards L, with a long horizontal base. Then the graph disappears.]
[TEXT: As our population has grown, so has our use of Earth’s resources.]
[A globe takes center screen. As it turns, we see land masses lit up by city lights at night, evidence of humanity’s presence on Earth.]
[TEXT: Choices we make today—family planning, pollution controls, reduced consumption,
habitat protection—will affect the future of our species, and all life on Earth.
[Credits roll.]