When salamanders misrepresent threat signals

Male red-backed salamanders (Plethodon cinereus) defend feeding territories in the forest and vary the intensity of defense depending on the quality o f food contained in their territories. Territorial quality was manipulated in a laboratory experiment by providing some residents with termites (a hig her profitability prey type based on rate of assimilation) and others with ants (lower profitability). Significantly more termite-fed than ant-fed res idents threatened and bit intruders. Both types of residents used honest si gnals (threaten and subsequently bite) and conventional signals (threaten b ut no subsequent bite). However, termite-fed residents spent significantly more time in threat posture when no bites followed than did residents fed a nts. Termite-fed residents did not show a significant difference in the amo unt of time spent in threat posture before biting relative to residents fed ants. The low energetic cost of threat displays may predispose residents t o "lying" (threat not backed up by a bite), but honest signals must be main tained for the conventional signal strategy to be maintained evolutionarily . Intruders are not likely to be "fooled" about the defensive intents of re sidents unless threat and subsequent biting are sometimes linked.