As per subject: why do chickens continuously lay eggs even if they are not fertilized?
Is this sort of behaviour found in other species of birds (or other egg-laying animals), or only in chickens? Is it natural, or domestic chickens have been specifically bred for it?
If it's natural, what kind of sense does it make to divert energies and nutrients to continuous lay unfertilized eggs which have no purpose other than being possibly eaten by someone else? How could such a wasteful reproductive behaviour have evolved? Even if it has been specifically selected for in breeding, it still seems to make very little sense in the first place.