Hardtoevolve
Hardtoevolve is a term used in evolutionary biology to describe traits or trait dimensions that show unusually low evolvability, meaning they resist rapid evolution even under sustained selective pressure. The coinage reflects the intuition that certain features are intrinsically difficult to alter because of deep developmental constraints, genetic architecture, or ecological trade-offs. In this sense, hardtoevolve is related to concepts such as evolutionary constraint, canalization, and genetic correlation, but emphasizes the relative inertia of the trait relative to other aspects of the organism.
Mechanisms: Traits can be hard to evolve because changes disrupt integrated developmental programs, produce deleterious pleiotropic
Examples and discussion: In theoretical work, complex binary or quantitative traits with strong functional integration—such as
Impact and debate: The concept is debated; some researchers view hardtoevolve as a useful heuristic for understanding