The earth that we live in today was formed nearly 4.5 billion years ago. Back then, the earth was a hot, molten body of rock where magma flowed freely. But eventually, our planet cooled and it gave rise to life roughly 3.5 billion years ago. Since then, life has followed a very diverse path and we have seen a multitude of organisms that have come and gone since then. Usually, Darwin’s Theory of survival plays a crucial factor in deciding what organism lives and what becomes extinct. But then, there are external factors that might lead to mass extinction events that rid the planet of life. Here are 3 cataclysmic events you wouldn’t read in any NCERT Solutions or even an NCERT textbook.
K-T Mass Extinction Event
65 million years ago, nearly three-fourths of all life on earth became extinct when an asteroid the size of a mountain slammed into the earth. This extinction marked the end of the dinosaurs and many other prehistoric organisms. The impact of the asteroid resulted in huge tidal waves around the planet and completely evaporating all life forms within a thousand kilometers around the impact site. Dust kicked up into the atmosphere and blocked out the sunlight, plunging the planet into a sudden ice age. This killed off most life on earth.
Gamma Ray Bursts
Gamma ray bursts are the most powerful events in the universe. They happen when a supermassive star goes supernova or when two neutron stars collide. The amount of energy they produce is gargantuan and it is insanely destructive. They last just a few seconds, but the energy output during those few seconds is equal to the energy produced by the sun during its 10 billion year lifespan. Also, they shine a million trillion times brighter than our sun.
Such an event which happened many light years away from earth is theorized to have caused at least one mass extinction event in the earth’s billion year history.
Granted, this did not happen yet, but this is a very real scenario when super powers around the world engage in nuclear warfare. In this scenario, the climate changes drastically, with temperatures dropping around the world. This is similar to an Ice age, but instead, the world will be covered with radioactive fallout. This makes earth uninhabitable, plant and animal life gets affected and eventually, earth turns into a barren wasteland. This threat is far more probable than any of the other events of the list.
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