How understanding the signaling within social networks can change the way we make decisions, work with others, and manage organizations. How can you know when someone is bluffing? Paying attention? Genuinely interested? The answer, writes Alex Pentland in Honest Signals, is that subtle patterns in how we interact with other people reveal our attitudes toward them. These unconscious social signals are not just a back channel or a complement to our conscious language; they form a separate communication network. Biologically based “honest signaling,” evolved from ancient primate signaling mechanisms, offers an unmatched window into our intentions, goals, and values. If we understand this ancient channel of communication, Pentland claims, we can accurately predict the outcomes of situations ranging from job interviews to first dates. Pentland, an MIT professor, has used a specially designed digital sensor worn like an ID badge—a “sociometer”—to monitor and analyze the back-and-forth patterns of signaling among groups of people. He and his researchers found that this second channel of communication, revolving not around words but around social relations, profoundly influences major decisions in our lives—even though we are largely unaware of it. Pentland presents the scientific background necessary for understanding this form of communication, applies it to examples of group behavior in real organizations, and shows how by “reading” our social networks we can become more successful at pitching an idea, getting a job, or closing a deal. Using this “network intelligence” theory of social signaling, Pentland describes how we can harness the intelligence of our social network to become better managers, workers, and communicators.

How understanding the signaling within social networks can change the way we make decisions, work with others, and manage organizations. How can you know when someone is bluffing? Paying attention? Genuinely interested? The answer, writes Alex Pentland in Honest Signals, is that subtle patterns in how we interact with other people reveal our attitudes toward them. These unconscious social signals are not just a back channel or a complement to our conscious language; they form a separate communication network. Biologically based “honest signaling,” evolved from ancient primate signaling mechanisms, offers an unmatched window into our intentions, goals, and values. If we understand this ancient channel of communication, Pentland claims, we can accurately predict the outcomes of situations ranging from job interviews to first dates. Pentland, an MIT professor, has used a specially designed digital sensor worn like an ID badge—a “sociometer”—to monitor and analyze the back-and-forth patterns of signaling among groups of people. He and his researchers found that this second channel of communication, revolving not around words but around social relations, profoundly influences major decisions in our lives—even though we are largely unaware of it. Pentland presents the scientific background necessary for understanding this form of communication, applies it to examples of group behavior in real organizations, and shows how by “reading” our social networks we can become more successful at pitching an idea, getting a job, or closing a deal. Using this “network intelligence” theory of social signaling, Pentland describes how we can harness the intelligence of our social network to become better managers, workers, and communicators.

Ever since Darwin, animal behavior has intrigued and perplexed human observers. The elaborate mating rituals, lavish decorative displays, complex songs, calls, dances and many other forms of animal signaling raise fascinating questions. To what degree can animals communicate within their own species and even between species? What evolutionary purpose do such communications serve? Perhaps most importantly, what can animal signaling tell us about our own non-verbal forms of communication? In The Handicap Principle, Amotz and Ashivag Zahavi offer a unifying theory that brilliantly explains many previously baffling aspects of animal signaling and holds up a mirror in which ordinary human behaviors take on surprising new significance. The wide-ranging implications of the Zahavis' new theory make it arguably the most important advance in animal behavior in decades. Based on 20 years of painstaking observation, the Handicap Principle illuminates an astonishing variety of signaling behaviors in animals ranging from ants and ameba to peacocks and gazelles. Essentially, the theory asserts that for animal signals to be effective they must be reliable, and to be reliable they must impose a cost, or handicap, on the signaler. When a gazelle sights a wolf, for instance, and jumps high into the air several times before fleeing, it is signaling, in a reliable way, that it is in tip-top condition, easily able to outrun the wolf. (A human parallel occurs in children's games of tag, where faster children will often taunt their pursuer before running). By momentarily handicapping itself--expending precious time and energy in this display--the gazelle underscores the truthfulness of its signal. Such signaling, the authors suggest, serves the interests of both predator and prey, sparing each the exhaustion of a pointless chase. Similarly, the enormous cost a peacock incurs by carrying its elaborate and weighty tail-feathers, which interfere with food gathering, reliably communicates its value as a mate able to provide for its offspring. Perhaps the book's most important application of the Handicap Principle is to the evolutionary enigma of animal altruism. The authors convincingly demonstrate that when an animal acts altruistically, it handicaps itself--assumes a risk or endures a sacrifice--not primarily to benefit its kin or social group but to increase its own prestige within the group and thus signal its status as a partner or rival. Finally, the Zahavis' show how many forms of non-verbal communication among humans can also be explained by the Handicap Principle. Indeed, the authors suggest that non-verbal signals--tones of voice, facial expressions, body postures--are quite often more reliable indicators of our intentions than is language. Elegantly written, exhaustively researched, and consistently enlivened by equal measures of insight and example, The Handicap Principle illuminates virtually every kind of animal communication. It not only allows us to hear what animals are saying to each other--and to understand why they are saying it--but also to see the enormously important role non-verbal behavior plays in human communication.

Gull chicks beg for food from their parents. Peacocks spread their tails to attract potential mates. Meerkats alert family members of the approach of predators. But are these--and other animals--sometimes dishonest? That's what William Searcy and Stephen Nowicki ask in The Evolution of Animal Communication. They take on the fascinating yet perplexing question of the dependability of animal signaling systems. The book probes such phenomena as the begging of nesting birds, alarm calls in squirrels and primates, carotenoid coloration in fish and birds, the calls of frogs and toads, and weapon displays in crustaceans. Do these signals convey accurate information about the signaler, its future behavior, or its environment? Or do they mislead receivers in a way that benefits the signaler? For example, is the begging chick really hungry as its cries indicate or is it lobbying to get more food than its brothers and sisters? Searcy and Nowicki take on these and other questions by developing clear definitions of key issues, by reviewing the most relevant empirical data and game theory models available, and by asking how well theory matches data. They find that animal communication is largely reliable--but that this basic reliability also allows the clever deceiver to flourish. Well researched and clearly written, their book provides new insight into animal communication, behavior, and evolution.

The reliability of animal signals is a central problem for evolutionary biologists. This text argues that it is maintained in several ways, relevant in different circumstances, and that biologists must learn to distinguish between them.

A landmark tour of the new science of "idea flow" outlines revolutionary insights into the mysteries of collective intelligence and social influence, explaining the virtually unlimited data sets of today's digital technologies and the considerable accuracy of information from social networks.