You can prove this by a DNA siblings test, it is the best way to prove a biological relationship
        
             
        
        
        
W33d is the answer duh as always
        
             
        
        
        
Answer:
gene flow
Explanation:
Gene flow, in simple terms, is a transfer of gene from one population to another. Also called as migration, where there is movement of individuals, and the genetic material they carry from one population to another. It also involves successful breeding of these individuals in their new locations. When people with sickle cell anemia were brought into the US, transfer of the gene responsible for sickle cell disease changed the frequency of the sickle cell allele in overall US population.
 
        
                    
             
        
        
        
Volume? Is that what you mean?