Stock market frenzies and crashes need not be due to exuberance or idiocy, but may reflect rational signaling and information herding. (by Tim Harford)

Employer life insurance is too costly due to adverse selection. Only the sickest employees sign up, leading to higher premiums.

In the evolutionary mating game, experienced partners of a number of species prefer weaker males, potentially as a signal of less abuse to come.

Summarizes a RAND article by Feltovich, Harbaugh To, which argues that, in a population of three types of people, the best types may send " countersignals."

How movie studios signal the dates of movie releases to avoid heavy competition.

Describes evidence of Amotz Zahavi's "handicap principle" by which risky, extravangant behaviors by many species of animals signal strength and ability.

Trees signal defenses to insects.

Trees signal defenses to insects.

Laying a final pale egg deters free riding "egg dumpers" by signaling that incubation has begun.

Poisonous frogs adopt different behaviors than their nonpoisonous kin, including brighter colors and dayime activity. (by Verne G. Kopytoff)

Only recently have economists provided explanations for the existence of advertising. It may be informative, reducing the lemons problem, or a commitment device, by "burning money." (by John Kay)

Justifies promiscuity and subsidization of condoms by examining probability, imperfect signals, and externalities