HARVARD UNIVERSITY PRESS, JUNE 2015Most of us have always felt that we tell the truth—or at least decide when to or not. Linguists, engineers, and most biologists have also always taken honesty for granted when studying communication. At one time, students of animal behavior did so, too.
Several decades ago, though, developments in evolutionary biology challenged this assumption. Communication might have evolved to be manipulative instead of honest. Natural selection should produce signals that maximize the spread of a signaler’s genes in a population, so signalers might evolve to provoke responses that benefit themselves regardless of the consequences for receivers. For instance, the songs of hooded warblers (Setophaga citrina) in a forest in eastern North America might have evolved to elicit mating by females, even if deceptive songs seduce a female against her best interest.
In subsequent decades, animal behaviorists have attempted to find a convincing explanation for the evolution of honesty in communication. One prevalent hypothesis is that honesty results from the high costs of producing extravagant signals. If only high-quality ...
