The dinosaurs become the pioneer species of planet earth
Dinsours are all evolved (climax community)
Dinsosaurs are the dominant species of planet earth (climax community)
Earth starts to shift continents, changes form, and warms up (ecological succession)
Meteor crashes the earth and wipes all all the dinosaurs (secondary succession)
The Water cycle gives run-off water to the earth and puts out fires and the niutrients from the waters restore the earth and the ecosystem. (eutrophication)