Final answer:
Punctuated Equilibrium is the theory that speciation occurs quickly at certain times, followed by long periods of stasis. Fossils often support this pattern, showing quick evolutionary changes after long intervals of little to no change, although both gradual and punctuated speciation can occur in evolutionary history.
Step-by-step explanation:
Punctuated Equilibrium refers to C. Periods of rapid speciation that are followed by long periods of little or no change. The concept of punctuated equilibrium is a model in evolutionary biology that contrasts with the idea of gradualism. This model suggests that the evolutionary history of a species is characterized by long periods of evolutionary stasis (little or no change) punctuated by shorter periods of rapid speciation. In this context, speciation is the process by which new genetically distinct species evolve from a single ancestral species.
According to punctuated equilibrium, these rapid changes may be precipitated by a variety of environmental factors, such as climate change, that exert significant evolutionary pressures on organisms. Fossil records often show evidence of this pattern, with long intervals where species remain unchanged, and sudden shifts where new species appear quickly. Punctuated equilibrium does not exclude the possibility of gradual speciation processes; rather, it acknowledges that both models can contribute to the evolutionary history of species.