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.
Answer:
The answer is C. Species diversity or B. Ecosystem diversity everyone thinks it either those 2 nobody really knows.
I’m not 100% sure but I think it’s small
Answer:
Ecosystem engineers are species that modify their environment in a significant manner, creating new habitats or modifying existing ones to suit their needs.
Answer:
The mechanism is natural selection.
Explanation:
Natural selection is the mechanism that these air-breathing fishes have gone through to survive. This mechanism allows species to survive and reproduce due to differences in the phenotypes of every individual in the specie, throughout the time the heritable traits that every individual inherits changes according to the environment and the characteristics of its ancestors.