Survival of the fittest means that organisms that are better adapted to their environment are best suited to survive and successfully reproduce.
"Survival of the fittest" is an expression, developed from Darwin's theory of evolution.
In this theory, he explained how to describe the process and mechanism of natural selection fully and in the most appropriate sense. The success of this physical biology concept can be determined by looking at reproductive success.
In Darwinian terms, the term existence in the most appropriate sense is best understood as "the existence of a form which in succeeding generations will leave most copies of itself." In the fifth season of "On the Origin of Species", by British naturalist Charles Darwin, the concept of survival of the fittest organisms became popular, which indicated that organisms adapted to the best with their environment are the most efficient in terms of survival and reproduction.
Darwin coined the phrase from Herbert Spencer, an English sociologist, and philosopher, who first uttered it in his 1864 book Principles of Biology.
Example: In one habitat, there are red bugs and green bugs. Birds love the taste of red bugs, so soon there will be more green bugs and fewer red bugs. Blue bugs reproduce and produce more green bugs and eventually no more red bugs.