Geologic Timeline

Three major events in Earth's history are when the dinosaurs went extinct, mammals went into existence, and Earth's temperature settled. The scale of Earth's history is long and shows the change in Earth in almost every way possible, from the organisms to the amount of water on Earth to the temperature on Earth. I was really surprised that we were able to learn and know about all of this. On our time on Earth, we probably impacted the temperature the most, raising it incredibly. My only question is why did Earth change in temperature. 
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