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Ever wondered how the surface of the Earth has changed over the millennia? Wonder no more.
Developers at Northern Arizona University have built a website called “Ancient Earth Globe”, which displays a rotating Earth suspended in a star-filled universe. To see what the Blue Planet looked like from space at any given geological period, users can use the drop-down menu at the top of the screen.
The animation allows users to travel back in time as far back as the Ediacaran Period, 600 million years ago – when multicellular life was only just starting to appear in the world's oceans – through to the present day, stopping off in the Devonian Period and Jurassic Period along the way. Each time zone comes with a small summary explaining what was happening at the time.
If you want to see what the Earth looked like when insects first appeared on the scene or the dinosaurs met their sticky end, you can. The developers also included a second drop-down menu that lets users jump to a particular event, for example, "the first coral reefs" or "Pangea supercontinent".
The globe was created by Ian Webster, a computer scientist working for the asteroid database Asterank in Mountain View, California, whose love of ancient history and geology inspired him to create an interactive tool to help youngsters conceptualize what the Earth looked like at various points during its long history.
Here are just a handful:
Early Cambrian, 540 million years ago
It's shortly after the world's first extinction, which wiped out the Ediacarans. This was brought about by a huge expansion in marine life – what we today call the "Cambrian explosion". It is around this time that animals start to evolve exoskeletons and shells.
Permian period, 280 million years ago
All landmasses merged to form the planet's second supercontinent, Pangea. (Scientists reckon the Earth will forge the third supercontinent sometime in the next 50 to 200 million years, which they are calling Amasia.)
While the ocean is full of life, extreme weather conditions like polar ice caps and deserts restrict the evolution of plant life. Where there is vegetation, amphibious tetrapods and reptiles flourish.
Middle Triassic, 220 million years ago
The Earth is recovering from its third extinction, the Permian-Triassic extinction, which wiped out 95 percent of life. The first dinosaurs appear on the scene, including the Herrerasaurus and Eoraptor, which are the size of a cat and a pony respectively.
Neocene Period, 20 million years ago
The very earliest hominids are just starting to emerge in Africa.
To put into perspective just how short humanity's lifespan is, imagine the universe's history as one calendar year. The Big Bang happened at midnight on January 1, life did not evolve on Earth until December 17, and modern humans didn't arrive until 11.54pm on December 31.
