There have been massive climate changes in the past, ever heard of the Ice Age.
This is the wisdom about Dinosaurs.
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Scientists theorize that the extinctions were caused by one or more catastrophic events, such as massive asteroid impact(s), or increased volcanic activity. Several impact craters and massive volcanic activity, such as that in the Deccan traps, have been dated to the approximate time of the extinction event. These geological events may have reduced sunlight and hindered photosynthesis, leading to a massive disruption in Earth's ecology. Many researchers believe the extinction was more gradual, resulting from a combination of the events above and others including sea level and climate changes.