Answer:
The given blank can be filled with reproduce.
Explanation:
According to Darwin's theory of evolution by Natural selection more individuals are generated in each generation, which can thrive. A phenotypic variation prevails between the individuals and the variation is heritable. When reproductive isolation takes place novel species will generate, and the individuals with heritable traits that better suits the surroundings will thrive. Thus, natural selection is a theory based on the tendency of a species to thrive and reproduce.
