Species change over time. -The mechanism that produces the change is natural selection: the differential survival and reproduction of individuals based on variation in their traits. Natural selection acts on individuals but individuals do not evolve; their descendants do.
On primary succession newly exposed or newly formed rock is colonized by living things for the first time. And in secondary succession an area that was previously occupied by living things
B.)Ecosystem
A community resides within an ecosystem, a population within a community, and an individual within a population