He observed 15 different finch species that originated as one ancestral bird. all differing in body shape, beak size, and mating habbits
        
             
        
        
        
A Mutation occurring in the population will change the allelic ratio.
<h3>What is evolution?</h3>
Evolution refers to the changes that occurs in organisms over a long period of time such that those changes results in new species better adapted to their environment and having higher specialization. 
One of the factors of evolution is mutation. 
According to the Hardy-Weinberg principle, the allele and genotype frequencies of a population of organism in equilibrium will remain constant in the absence of evolutionary influences.
Therefore, if a mutation occurs in the population, the allelic ratio will change.
Learn more about Hardy-Weinberg principle at: brainly.com/question/1365714
 
        
             
        
        
        
Answer:
The correct answer would be divergent evolution showing by homologous organs.
Explanation:
In the illustration human arm, the flipper of the dolphin, wings of bat and forearm of frog are shown. All  these four forelimbs have a different function, however, these forelimbs are having the same underlying anatomy. 
The organs having basic structure and origin, but different functions are known as homologous organs. These organs point towards the same ancestor from these organisms evolved. They show a case of divergent evolution.
When related species become less similar in order to adapt and survive in different conditions, evolution is called divergent evolution.
Thus, these forelimbs provide evidence for divergent evolution.