On Pentecost Island, Vanuatu, in the South Pacific, men perform a terrifying ritual akin to bungee jumping. "Land diving" entails jumping head-first from a platform up to 30 metres tall, with just two tree vines wrapped around their ankles and no safety net.
Such highly rousing rituals are known as rites of terror and are extremely effective at binding groups together. One reason is that people tend to be more committed to a group, and tolerate its shortcomings, when they have paid a high price for entry. Another is that rites of terror are highly memorable, creating vivid and shocking "flashbulb" memoriesthat remain with participants for a lifetime.
Such rituals are usually infrequent, often once in a lifetime, but land diving was originally performed annually and now occurs weekly from April to June as a tourist spectacle. It remains a rite of passage to manhood for the boys of Pentecost Island.
Eunoto, the coming-of-age ceremony for Masai men, consists of several days of rituals including adumu, the jumping dance. The young men form a circle and take it in turns to jump as high and straight as they can, while the others chant. As the dancing continues, they often become entranced, partly under the influence of an intoxicating drink made from a bark infusion, and partly due to the rhythmic nature of the activity.
Such rhythmic repetition is characteristic of many rituals because it creates focus and a sense of bonding among group members. Repetition is especially common in the rituals of world religions, such as the Catholic mass and Muslim prayer, known as salat, which is preceded by ritual ablution and usually performed five times a day.
This reflects another benefit of repetition – it reinforces the beliefs of the group by fixing them firmly in the memory of those who participate in its rituals.
Made famous by New Zealand's All Blacks rugby team, the haka is a traditional Maori dance that includes vigorous movements, facial contortions and chanting. Today, haka are used in various events, from welcoming visiting dignitaries to funerals, but they were originally performed by warriors before battle.
The war haka (peruperu) was designed to intimidate the opposition, and synchrony was important: performing it out of unison was considered a bad omen for the coming fight.
Synchrony is key to many rituals because it increases social cohesion, one of the main purposes of ritualistic behaviour. Robin Dunbar at the University of Oxford has found thatrhythmic activities such as dancing and chanting stimulate the release of endorphins, neuropeptides that promote a sense of connection and trust.
A Japanese tea ceremony can last up to 4 hours. Strongly influenced by Zen Buddhism, centuries of history have resulted in many variations of this practice, each with its own elaborate procedures that vary with the time of year and day, venue and other things.
Such complexity is the hallmark of a good ritual. In fact, the more steps a ritual has, and the more precise these are, the more highly people rate it. That, at least, is what André Souza at the University of Alabama in Tuscaloosa and Cristine Legare from the University of Texas at Austin found when they asked people to rate rituals. For the purposes of their study the researchers had invented practices based on Brazilian simpatias – which are bought like recipes over-the-counter and designed to help people achieve goals such as finding a new job or romantic partner.
If rituals help groups bond, it is hardly surprising that many aspects of military life are ritualistic – from how members of a unit make their beds to the precise details of their drill.
Like many rituals, these practices often appear nonsensical. For example, the way the Greek soldiers known as Evzones march when changing the guard at the Tomb of the Unknown Soldier in Athens doesn't seem to achieve a specific purpose. Intriguing new research suggests that when we observe such "causal opacity" our minds switch from their normal way of thinking into a ritual stance. This happens even in infants and seems to prompt children to copy nonsensical actions even more faithfully than actions with obvious goals.
Douglas, Kate. 2015. “Five bizarre rituals – and why people perform them”. New Scientist. Posted: January 15, 2015. Available online: http://www.newscientist.com/gallery/rituals