Haldane's dilemma

Haldane's dilemma addresses the question of how quickly natural selection can produce significant genetic change in a population. It suggests that each beneficial trait, when it becomes common, requires a certain number of reproductive "turnovers" or generations for the entire population to adopt it. If multiple traits are evolving simultaneously, the total reproductive effort needed can exceed the population's capacity, implying there’s a limit to how fast evolution can Occur through natural selection alone. Essentially, it highlights a potential constraint on the rapidity of evolutionary change due to biological and reproductive limitations.