It’s probably something you’ve thought about while lying awake at night, sending you spinning into an existential crisis – what did the world look like before life grew on earth?
To find out, Cosmos Magazine journalist Evrim Yazgin had to go back in time, four billion years to where it all began.
While there are plenty of different theories outside of natural evolution, Evrim explains how earth went from a large, barren rock floating through space to a fully thriving ecosystem with lush greenery and vast oceans and eventually, life.
From Soup to Us: Our Four-Billion-Year Journey on Earth
So, when exactly did Earth see its first sign of life? According to Evrim, it was around 540 million years ago.
“It’s at about this time in our planet’s history that an event called the Cambrian Explosion took place. This was an explosion, not of gunpowder or other substance, but of life,” he said.
“The Cambrian Explosion reflects a slice of the fossil record, which indicates a flourishing of many different types of organism for the first time in Earth’s history, all the major animal body structures that we’re familiar with today first emerged during the Cambrian.”
These initial signs of life included the world’s first arthropods which were the ancestors of insects such as scorpions, spiders and other insects.
But what about humans?
Evrim takes us on a scientific journey through time, revealing what the world looked like before humans populated the earth and how humans came into existence.
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