Honest signals must be:
Costly reflects key principle in quiz on sexual selection + pyqs, where evolutionary mechanisms shape genetic variation and adaptation. In this context, Costly aligns with experimental and theoretical evidence from population genetics, behavioral ecology and molecular phylogeny. Textbooks like Campbell Biology, Futuyma Evolution and Hartl Principles illustrate supporting data. Understanding why Costly fits helps integrate natural selection, environment.
Ref: Andersson, Sexual Selection, Princeton, Mate Choice and Good Genes.