<u>Answer:</u>
<em>In highly diverged lineages, the substitutions process will occur at sites that have been substituted previously</em>.
<u>Explanation:</u>
Molecular clock uses the mutation rate to reduce the time in prehistory when the life forms are diverged. <em>The molecular clock uses the sequence of amino acids and nucleotide sequence for the DNA.</em>  
This clock does not measure any time but the number of mutations, and other changes over certain time.  <em>Sometimes its useful property might be limited due to the highly diverged lineages.</em>
 
        
             
        
        
        
Th earth scientists have improved our understanding with the environment because of their studies in which they had shown better understanding and explanation of occurrences with the means of having to provide not only explanation nor visuals but also providing proof of these mere existence that made people believe and understand the environment.
        
             
        
        
        
During an El Nino, warm water gathers along the West coast of South America, so the nutrient rich water is no longer being upwelled. keeping in mind that cold water sinks and warm water rises, usually the warm water near coastal regions would not be full of nutrients compared to the cold water where the nutrients fall. therefore, more fish will be located or migrate to areas of this nutrient rich cold water instead. So, many fishermen would not have high yields of fish ultimately affecting their way of life and money. also a lot of these fish that remain at the surface would not be as healthy or nutrient rich. 
hope that helps! :))
 
        
             
        
        
        
Answer:
Attached R side groups
Explanation:
The proteins are one of the important biomolecules which are directly coded by the genetic material of an organism.
The proteins are composed of the amino acids which possess, an amine group, a carboxylic group and an attached side group called the R group.
It is the R group of an amino acid which determines whether the amino acid will a polar or a non-polar amino acid molecule thus it determines the properties of the amino acid in terms of chemical properties. The R side group are involved in the formation of bonds with the substrate of the environment and the tertiary structure of the proteins.
Thus, the presence of different R group is the key difference in 20 amino acids.