65 million years ago: Dinosaurs go extinct.
65 million years ago, in what today is the Yucatan Peninsula, a meteorite fell which caused intense climate change and 65% of species went extinct. The consequences of the disaster were many. Among others, there was darkness, vast amounts of toxic dust in the atmosphere and a decrease in temperature.
The asteroid crossed the Earth’s atmosphere in about a second, heating the air in front of it reaching temperatures similar to the temperature of the sun.
Almost all dinosaurs that had ruled the planet since they inhabited sea, land and air, disappeared. Perhaps what affected them most was that due to darkness, which probably lasted several months, all plants died from lack of sunlight, and this caused a decrease of oxygen in the atmosphere. Herbivorous dinosaurs died first, and carnivorous dinosaurs, which were their predators, went extinct too eventually.
On land, anything heavier than 25 kilos died.
We know present birds evolved from the few dinosaurs that survived. The other species which were able to escape and fill the ecological niches the dinosaurs left empty are the mammals. Since they were initially tiny animals living in burrows, they were able to find shelter and insects for food.