Explanation:
because the tilt of the earth on its axis
 
        
                    
             
        
        
        
Explanation is in a file
bit. ly/3a8Nt8n
ly/3a8Nt8n
  
        
                    
             
        
        
        
Answer:
If both parents do not have sickle-cell anemia, than the possibility is low.
Explanation:
If both parents have the sickle-cell trait, their offspring has a 25 percent chance of getting sickle cell anemia and a 50 percent risk of them having sickle cell trait. Meanwhile, there is also a 25 percent chance of the child not getting it at all.
If one parent has sickle cell anemia and the other has sickle cell trait, then their offspring with have a 50 percent chance of getting sickle cell anemia and a 50 percent chance of getting a sickle cell trait.
When both parents have sickle cell anemia, their child will definitely have it.  
 
        
                    
             
        
        
        
Answer:
In biology, a molecular clock can be described as a method to determine the time for the divergence of species which occurred by the process of evolution. 
Explanation:
The mutation rates of different molecules are used in this method. The mutation rates for DNA sequences and amino acid sequences are usually considered. The molecular clock can be used to compare and estimate the splitting of a lineage. For example, by this method, one can interpret when the chimpanzees and humans diverged from each other.
Hope this helped!
-Toshino
 
        
             
        
        
        
Answer:
D
Explanation:
Just trust me.  
it's not A because there's no such thing as favorable traits whenever it comes to incesticide and for B the majority of Beatles and future generations will also die that's only to the ones that died but that can not happen, which means that D is the one that will be the correct answer because if one lives, then the rest of the generations live due to immunity in the generation that started it.