Which concept was not included in Charles Darwin's theory of natural selection?
A. Struggle for existence.
B. Punctuated equilibrium.
C. Survival of the fittest.
D. Overproduction of offspring.
Darwin's theory of natural selection states that species tend to overproduce due to limiting resources. This sets up competition or a struggle for existence. Those most fit in that environment are likely to survive, passing those favorable genes on to their offspring. In time, a new species evolves from the accumulation of favorable genes. Punctuated equilibrium is a theory that was formulated after Darwin's theory and it states that species remain relatively stable for long periods of time and then, due to some natural catastrophe, change rapidly in a short period of time.