Which is the change in size of a group of organisms of the same species over time?
population growth
death rate
birth rate
immigration and emigration

primary succession occurs in essentially lifeless areas regions in which the soil is incapable of sustaining life as a result of such factors as lava flows, newly formed sand dunes, or rocks left from a retreating glacier. secondary succession occurs

1. is geographic distribution

2 is increasing complexity

3 is transitional forms