>[!abstract] >The handicap principle is a disputed hypothesis proposed by the Israeli biologist Amotz Zahavi in 1975. It is meant to explain how "signal selection" during mate choice may lead to "honest" or reliable signalling between male and female animals which have an obvious motivation to bluff or deceive each other. The handicap principle suggests that secondary sexual characteristics are costly signals which must be reliable, as they cost the signaller resources that individuals with less of a particular trait could not afford. The handicap principle further proposes that animals of greater biological fitness signal this through handicapping behaviour, or morphology that effectively lowers overall fitness. The central idea is that **sexually selected traits function like conspicuous consumption, signalling the ability to afford to squander a resource**. Receivers then know that the signal indicates quality, because inferior-quality signallers are unable to produce such wastefully extravagant signals. >[!quote] Rory Sutherland makes this point [about understanding a Chesterton's fence before removing it] with the example of a peacock’s tail. The tail’s value lies in its very inefficiency—it signals that a bird is healthy enough to waste energy growing it and strong enough to carry it around. Peahens use tails to choose mates with the best genes for their offspring. If an outside observer were to give peacocks regular, functional tails, it would be more practical, but it would strip away their ability to advertise genetic potential ([[Farnam Street, n.d.]]). >[!quote] >Sexual selection has provided a successful theoretical framework in evolutionary biology. It has offered an explanation for many animal traits and behaviors, from birdsong to tusks and horns.1These characters do not usually aid survival but are essential in mating displays and rival confrontation. In addition, their presence and salience tend to correlate with the animal’s overall health, thus they are hypothesized to serve as indicators of individual fitness. The classic example is the peacock’s tail, whose large, colorful, eye-spotted feathers incur a huge energetic investment. While attractive to the peahens, the tail makes the male bird less agile and more noticeable to predators. So, those peacocks that despite the handicap of the costs and risks of the tail are still able to sustain and display it conspicuously should be perceived as high-quality mates and preferred by the peahens, whose offspring will inherit both the elaborate tail (the males) and a preference for it (the females). This is broadly the basis of the so-called "Handicap Principle" (Zahavi and Zahavi, 1997), also known as "fitness indicator" model of sexual selection ([[Straffon, 2021]]). >[!quote] >Finally, great brands understand that their marketing communications need to act as a signal to others. As a result, it’s their behavior rather than the message itself that matters. In some cases, these signals can be of trust (as Rory Sutherland puts it, "we send wedding invitations on gilt-edged cards, and not by email, precisely because the expense of doing so signals our commitment to the union") ([[Kay, 2017]]). >[!related] >- **North** (upstream): — >- **West** (similar): [[Aposematism]]; [[Conspicuous consumption]]; [[Veblen goods]] >- **East** (different): — >- **South** (downstream): —