Although any disaster on this list could eliminate people from the face of the Earth, humanity could have asteroids, glaciation, collision of planets or devastating eruptions to thank for its existence, since it finally allowed Homo sapiens to appear and prosper.
Intelligent life on Earth appeared in a delicately balanced environment, formed after a series of global catastrophes, which have led some to describe them as blows of good luck to humanity. What exactly made us so lucky?
Birth of the moon
The satellite of our planet, the Moon, which dramatically impacts life on Earth, was born 4.5 billion years ago as a result of a major catastrophe, scientists concluded after studying its soil. In the young and disorderly solar system, the newly formed Earth supposedly collided with a Mars-sized glider, sometimes called Theia. Although a piece of Earth was lost and our planet changed its axis, the unwanted guest was destroyed.
The debris resulting from the collision formed the Moon when gravitation gathered them approximately one million years later. While the inclined axis contributed to the appearance of four seasons, the Moon and its attraction prevented the iron core within the Earth from hardening. This allows our planet to have an oxygen atmosphere, which protects us from ultraviolet radiation and from asteroids. Without all this, life on Earth, as we know it, would be hard to imagine.
Earth has also had several periods of extremely low temperatures, with the two colder times particularly important for the development of life. The first severe period, called Huronian glaciation (or Makganyene glaciation), occurred 2.4 billion years ago and lasted 300 million years. Although life existed at that time, it was limited to microorganisms. Then, these bacteria managed to survive to become more complicated organisms.
Another important glaciation, which supposedly occurred 720–635 million years ago when there were creatures similar to sponges and marine bacteria, is called sarcastically the ‘Snowball Earth’. As one of the hypotheses suggests, the temperature reached -43 ° С around the equator. However, the supposed puddles in the equator and near the mountain tops remained, which helped these creatures to survive: what would be their chances if this period lasted longer, we can only assume.
Siberian traps born
Another major catastrophe, which, on the contrary, warmed the Earth, occurred 252 million years ago. At that time, the planet witnessed a massive eruptive event in what is currently Siberia, which is located in the north of the former Pangea supercontinent. More than 5 million cubic meters of basalt were brought to the surface, forming fascinating landscapes, along with ashes and poisonous gases.
It coincided with the period of mass extinction when 96% of marine creatures and 70% of terrestrial vertebral animals disappeared, as well as 83% of insect species. This event was called the Permian extinction. However, as scientists suggest, this was not the only effect of the rash. The latter probably triggered other biosphere processes, directing evolution in the course that eventually led to the appearance of humans.
Another period of mass extinction came 66 million years ago, eliminating creatures that had ruled the Earth for 250 million years, the dinosaurs. Together with other large and medium-sized animals and three-fourths of all existing plant and animal species disappeared in the Cretaceous-Paleogene extinction event, supposedly caused by an asteroid attack.
This space host, which landed in the Gulf of Mexico, caused a giant tsunami, in which many land animals drowned in North America, and dust storms, which protected the surface from the sun. It became harder for plants to grow, so larger species could not get enough food to feed. However, it is believed that the event gave mammals the chance to survive. The latter could not compete with the cold-blooded giants, but as soon as they were out of the way, the mammals seized the opportunity to thrive and evolve.