Answer:
Natural selection is an evolutionary process which occurs over hundreds and thousands of years. These effects are visible when we look closely at a population, because they surpass the lifetime of an individual. Moreover, the process of natural selection is involved with the evolution of a whole species, and not just a single individual.
Step-by-step explanation:
Charles Darwin gave the theory of natural selection to define the process of biological evolution. This theory states that the individuals of a species with heritable traits that are superior or better suited to their environment will survive, and this process continues over time. This leads to the formation of a new species with the continued process of natural selection.
when looking for the evolutionary effects of the natural selection, one need to look over the selected population over a period of time to see the evolved inherited characters. An individual may or may not have these evolved characteristics, and hence, looking at a single individual of a species will not be a success.