Two examples of how the biosphere supports life is by reducing the amount of harmful radiation to reach the surface of the earth. It also gives oxygen for animals to breathe
        
                    
             
        
        
        
You are exercising, doing aerobics or a stair climber at your fitness center. as you increase to a high intensity of exercise, you would expect the tidal volume to increase and the frequency of respiration to increase. 
        
             
        
        
        
The answer is a half-filled circle. 
In the pedigree charts, squares present males and circles present females. If a female is healthy, the circle is empty (white). If a female is affected with a trait, the circle is filled-in (usually black). However, if a female is a carrier of a disease, which means that one allele is dominant and one is recessive, then the circle is half-filled. 
        
                    
             
        
        
        
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.