Signaling is a very basic biological phenomenon. It is present at almost all levels of biological organization and it plays a crucial role in nearly all biological processes. Although these processes comprise a very diverse set of phenomena, there is a common core to their structure: at least one sender interacts with at least one receiver. This allows one to apply the mathematical theory of games, which is an abstract theory of strategic interactions. The goal of this project is to identify stable evolutionary outcomes of signaling interactions by using methods from evolutionary game theory. Although some properties of signaling are well understood, our knowledge of how reliable signaling emerges in a dynamic process is limited, especially in cases where there is substantial conflict of interest between a sender and a receiver. If it is not in the sender's interest to transfer all relevant information, how can reliable signaling be achieved? This question is at the heart of a huge number of problems in biology. It also plays a very prominent role in many economic interactions. This project will provide important new results for a wide array of research programs and will open up unknown paths for experiments and field studies. The project involves the training of undergraduate and graduate students and the development of educational tools.
Communication occurs all throughout the biological world. Bacteria signal to one another. The cells in your body are communicating in a vast number of ways right now. Animals of all types are communicating with one another. I am communicating with you right now. Despite its ubiquity, there is much that is unknown or misunderstood about communication. Why do people and other creatures tell the truth even when there is an incentive to lie? Why do some animals evolve to communicate while others don't? What can be done to prevent deception in human, animal, (and even computer) interaction? In biology and economics, there is a dominant answer to this question. It's called the "handicap principle" in biology and "costly signaling theory" in economics; although they both amount to the same thing. The idea is that if there is some cost to communication (if talk is not cheap) then lying can be unprofitable and honesty will be the norm. It is fair to say that most biologists and economists think this is the beginning and the end of the story about signaling. We have argued otherwise. One result of our research is to suggest that this dominant way of understanding signaling is incomplete. It does not answer all the relevant questions, and the answers it does give are somewhat misleading. One of the most serious problems is a form of the "chicken and egg" problem familiar to almost anyone. Suppose that it is very expensive to talk to someone else. It only makes sense to start talking if your partner is listening. And, it only makes sense to listen if someone else is talking. But, most organisms started out by not communicating. So, if talk is not cheap, why did anyone start talking if no one was listening? And if no one was talking, why was anyone paying attention in the first place? We provide a number of mathematical models that make this concern precise and demonstrate that is more than just a verbal puzzle – it represents a significant shortcoming of the traditional picture of signaling. Criticism is helpful, but we hope we have gone further. We have offered a number of alternative theories for how communication can evolve and how honesty can be sustained. To illustrate their plausibility we have invented a number of new mathematical models which show that our theories should be taken as viable contenders to the traditional theory. We suggest that rather than one answer, there are several, to the questions above. Our novel solutions will help us both to understand the natural world as it exists now, and will also help us to design institutions which will help to ensure honest communication. Economists and computer scientists are interested in how institutions and protocols can be designed to ensure honesty – even when people have an incentive to lie. We believe that by taking inspiration from the natural world, new institutions can be designed that will help to ensure honest communication.
