Final answer:
Survival of the fittest is a concept within natural selection indicating that those individuals with advantageous traits are more likely to survive and reproduce. It relates to natural selection by describing how these traits become more common in populations over time, and does not refer to evolution, which is the broader process encompassing such changes.
Step-by-step explanation:
Survival of the fittest refers to the concept that individuals with traits better suited to their environment have a higher likelihood of surviving and reproducing. This is an indication of natural selection rather than evolution because it describes the process through which advantageous traits become more common in a population over time, as individuals with these traits are more likely to survive and pass them on to their offspring. Evolution occurs as a result of this process, with populations changing over generations, but survival of the fittest itself pertains to the specific mechanism through which natural selection operates.
In the context of natural selection, 'fittest' can refer to various types of fitness, such as an organism's speed, its camouflage abilities, or even its appeal to potential mates. For instance, a brightly colored male bird might be chosen by females over a larger, less colorful male, illustrating that biological fitness has to do with an organism's ability to survive and successfully reproduce within its environment.
It's also crucial to recognize that sometimes less-fit individuals might survive and reproduce, leading to their traits dispersing through a population. Such scenarios demonstrate the complexity and variability of natural selection. Moreover, adaptations that enhance an organism's survival and reproductive prospects are not fixed but vary as environments change, requiring natural selection to continually adjust the traits present in a population.