Asteriod Imoact: When an asteroid hits the earth. They are generally much fainter than asteroids of comparable size, and they are. The environmental effects of impact events differ with respect to time. (seconds to decades) and spatial (local to global) scales. 65 million years ago this happened.
Climate Change affects the food chain because it's hard to grow food when it's cold and if it's freezing, a lot of animals die out.
Volcanic Activity: an opening in the earth's crust from which molten lava, rock fragments, ashes, dust, and gases are ejected from below the earth's surface. Volcanic eruptions can have local effects on humans and on wildlife habitats. When ash and gases from a large volcanic eruption spread around the planet, they may absorb and scatter enough sunlight to cause a temporary decrease in the average global temperature. It ended the Paleozoic Era.