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.
 
        
             
        
        
        
I think The number of mice would increase because the birds can’t eat them if they die off
        
             
        
        
        
Answer:
Biodiversity is a variation of organisms (plants, animals and bacteria) in the world or a specific habitat. Biodiversity helps to keep an ecosystem healthy because there is more variation of food and different organisms can rely on each other for survival. Also it offers a larger more reliable food chain and if one species is suddenly wiped out, it won't impact the ecosystem as much as it would if the biodiversity was smaller.
Explanation: