If planet Earth were a person, it would have a lot of stories to tell (not to mention a next-level Instagram feed and the wisdom of about a hundred thousand grandparents). Birth, death, ice ages, empires, microbes and mammals and Pokémon™ Go. From the moment it burst into existence as a molten ball of magma, Earth has pretty much been a no-dull-moment place.
We’ve imagined what it would be like to flip through planet Earth’s photo album and take a look at a few of its particularly important milestones. They’re the moments your Mom would make you dress up for, and they’re the memories that will last a lifetime (or two, or seven billion).
So on your marks, get set, say “CHEESE!”
Far from an adorable newborn, early Earth was a terrifying, chaotic, molten thing. Much like a newborn, however, it came into existence screaming and crying (so to speak).
Around 4.5 billion years ago, rock and ice orbiting the early Sun collided into a small, rocky planet under the force of gravity, and our infant planet continued to be battered by many objects, some the size of planets. The energy of these collisions kept early Earth incredibly hot and much of its material remained molten. Heavier elements sank to the bottom of the magma ocean and lighter material bobbed to the surface. Eventually layers started to form as this process continued. The surface cooled and solidified into a crust as the number of impacts from space fell, and the planet gradually settled into the layers we’re familiar with today.
Not an easy birth, then.
Everyone needs a good friend they can rely to provide love, support, laughs, and solar radiation to use in energy-producing chemical processes. Right?
Between 4.1 and 3.8 billion years ago, planets shifted their orbits in a cascade of gravitational disruption, and the process left eight major planets in orbit around the Sun. This included Earth, which is held by Sun’s loving gravity to this day. Our planet continues to count on this enormous star for light, warmth and live-giving energy.
Since Earth’s layers stabilized four billion years ago, its tectonic plates have been constantly moving, gradually changing the appearance of our planet. The map of our modern world is a familiar image, but the current arrangement of continents is a relatively recent development in our planet’s history. Think of it like a series of outfit changes – except instead of hats and shoes, the collision of tectonic plates can cause entire mountain ranges to form. The Himalayas, for example, were created when the Indian plate slammed into the Eurasian plate around 50 million years ago. How’s that for a new accessory?
About six hundred million years ago there was a party on Earth and everyone was invited. It was all the regular VIPs: anthropods, sponges, the usual. The occasion was the first big explosion of animal life, in oceans already alive with algae and microbes. From modest beginnings as creepers and grazers on the sea bed, animals quickly evolved into all the main groups alive today.
By the time of the Cambrian Explosion, all major kinds of living animals – flatworms, molluscs, and anthropods included – had evolved. But other, less familiar types evolved alongside them, and some fossils suggest the existence of animals very unlike anything alive today. Many of these ancient types disappeared without leaving lasting descendants, but others went on to fill the planet with animal life (they kept the party going, pretty much).
It was around 3300 BCE that Earth learned its ABCs. Writing began in ancient Egypt and Mesopotamia as a way to store vital information. Pictographs could stand for words, ideas and sounds, and were used to keep things like economic records.
Earth made its first papyrus around 3000 BCE in Egypt, printed on paper in China in the 1st century CE, and invented the moveable-type printing press in the 15th century (with the help of a clever guy named Johannes Gutenberg).
Earth has a pretty varied résumé, but from around 9600 BCE, it added something new to its list of skills – farming.
As global temperatures rose rapidly, humans were forced to find new ways to hunt and gather, and foragers across the world discovered new ways to boost their food supplies, most dramatically by farming. Instead of continually moving to find food, they could now settle permanently in one place.
The first farmers worked the land with wooden digging sticks and stone-bladed hoes and adzes, and could grow just enough crops to feed their families. Talk about upskilling!
In the mid-18th century, Earth decided it was a time for a change, and a big one. After hundreds of years of slow development, a series of innovations in Britain began a process that would change the world forever. This process is now known as the Industrial Revolution.
The Industrial Revolution transformed agrarian societies that discovered how to use fossil fuels like coal to replace human and animal power in manufacturing, communication and transportation. It began in Britain, when several factors – both global and local – ushered in an era of relatively fast technological change. This period can be characterized by new production methods, more efficient transportation networks, and the rapid growth of cities. Shiny new career change complete.
Over the last 250 years, Earth decided it was high time to upsize its family. In 1800, there were 900 million people in the world; by 1900 there were 1.6 billion; by 2000 there were 6.1 billion; and today the world population has reached over 7 billion.
That’s a lot of mouths to feed and a lot of bodies to clothe, though! As a species, we’re using 24 times as many resources as we used 100 years ago. If we’re going to take the strain off of Earth, we’ll need to start helping out around the house by finding sustainable solutions and taking better care of our only home.
Featuring a foreword by the father of Big History, David Christian, and produced in association with the Big History Institute, Big History provides a comprehensive understanding of the major events that have changed the nature and course of life on the planet we call home. This first fully integrated visual reference on Big History for general readers places humans in the context of our universe, from the Big Bang to virtual reality.