Answer:
Four conditions are needed for natural selection to occur: reproduction, heredity, variation in fitness or organisms, variation in individual characters among members of the population. If they are met, natural selection automatically results.
Explanation:
Evolution, in genetic terms, involves a change in the frequency of alleles in a population over time. What are the sources of genetic variation? Three sources of genetic variation are mutation, genetic recombination during sexual reproduction and lateral gene transfer.
 
        
             
        
        
        
Answer:
Explanation:
a bird feather is biotic because it was made on a living thing. fog is abiotic because its not  living or was never living. i might be wrong about the feather tho.
 
        
             
        
        
        
serving size is a set portion created by the government. it is the optimal amount of food/liquids to be consumed by one person.