Punctuated Equilibrium is a theory in evolutionary biology that suggests species experience long periods of stability, or equilibrium, interrupted by brief episodes of rapid change. This contrasts with the traditional view of gradual evolution, where changes occur slowly and continuously over time. The theory was proposed by paleontologists Niles Eldredge and Stephen Jay Gould in 1972. They based their ideas on fossil records, which often show sudden appearances of new species followed by long periods where little change occurs. This model helps explain the patterns observed in the history of life on Earth.