One billion years ago, Earth was boring as hell. Animals were yet to evolve and most life was small, simple, and slimy. Even if you were to go sightseeing during this period, you’d be grossly disappointed by the view; the planet was weirdly flat with no towering mountains, but plenty of featureless oceans covered in stinking scum.
It was such an unremarkable chapter in Earth’s history that scientists have called it the “boring billion.” Some researchers have tried to push back against this label, claiming the period was more dynamic than previously thought, but it’s safe to say it was relatively eventless compared to the rest of Earth’s wild past.
Between 1.8 billion and 800 million years ago, Earth entered a long period of relative stasis, marking little change in biological evolution, geology, climate, or the chemical composition of the ocean and atmosphere.
In 2021, scientists published a study that showed this period was also a time of unremarkable tectonic plate activity, creating a period of significantly reduced mountain building.
Mountains are formed by tectonic plates slowly crashing into each other, causing them to crumple up at the scene of the collision. This is how the Himalayas were formed around 50 million years ago, when the Indian tectonic plate smooshed into the Eurasian plate, causing huge amounts of Earth’s crust to be displaced and forced up.
The researchers discovered evidence indicating that during Earth’s boring billion, the crust was thinner and more uniform than it is today, to the point where no mountains existed. Instead, the planet was dominated by vast oceans and flat landmasses. These conditions imply that tectonic activity likely slowed significantly or ceased entirely for about one billion years.
Interestingly, tectonic activity might have been the defining factor of this achingly dull period. The shifting of tectonic plates helps enrich the world’s oceans by stirring up sediment and crust, releasing more nutrients into the water. An abundance of nutrients creates a fertile environment that encourages life and the evolution of more species. Without tectonic movement, the oceans can become stagnant and less dynamic, slowing the rate of evolution.
It’s not clear why tectonic activity ceased during the boring billion, nor what reignited it. Yet, when Earth’s crust began to stir once more, it ushered in sweeping transformations to the atmosphere, oceans, and life. As boring as it may seem at the surface, this period is a good reminder that Earth’s systems are deeply interconnected and inseparable from one another.
Source Link: During The "Boring Billion", Earth Was Weirdly Mountainless – Then It All Changed
