Are unusually colored eggs a signal to potential conspecific brood parasites?

It has previously been suggested that some species of birds make the last e gg in their clutch pale as a signal to potential conspecific brood parasite s that incubation has commenced. Here, we use game theory to show that the signaling function of pale eggs can be evolutionarily stable and resistant to cheating and to demonstrate that such a signal can only be maintained un der strict conditions. The key conditions are, first, that there is a cost associated with the production of pale eggs (in particular, the cost of a p ale egg produced early in the clutch must be more expensive than the cost o f one produced later in the clutch) and, second, that the cost of making th e last egg pale is not too great (relative to the costs of parasitism). We discuss the likelihood of these conditions being met in real systems and su ggest empirical tests that would differentiate this theory from alternative nonadaptive explanations for pale eggs.