Answer:
Increase
Explanation:
It helps you to se better.
 
        
             
        
        
        
Answer:
erosion
Explanation:
rain moving soil is the earths crust slipping, also known as erosion
 
        
             
        
        
        
<span>Biomes are defined as the world's major communities, classified according to the predominant vegetation and characterized by adaptations of organisms to that particular environment.</span>
        
             
        
        
        
Answer:
I would expect to see a new phenotype in which the new duck hybrid species would express a new mixed courtship dance with the behaviors of both parentals.  
Explanation:
The cross between both parentals, each from different species, might produce a new phenotype that exhibits both parental dances. The new dance might be considered a hybrid of the parental dances. 
Genetically speaking, we can think that there is a gene codifying for the courtship behavior in one species and another gene expressing a different courtship behavior in the other species. This cross´ product would be a hybrid species that exhibits a part of both parentals´ behaviors. 
 
        
             
        
        
        
Description 2 describes a commensal symbiosis.  The answer is D, commensalism.