The primary succession takes a long time to be done. the secondary succesion takes 200-500 years for completion. the secondary succession occurs in an area which has been denuded recently and lately inhabited. soil is present at the beginning of the secondary succession with some organisms. thank you for this question.
Answer:
theory
Explanation:
a theory results from a proven hypothesis
Answer:
You take any of the "signs of change in populations of organisms and their environments". For imagine, Australopithecus (early man) turning to Homo sapiens. In that way they could tell that you took this journey.
by experimenting the layers of the earth
D. an arctic fox is brown in summer and white in winter