"Long before it's in the papers"
December 28, 2013


An evolutionary role for “Jackass”-like stunts?

Dec. 28, 2013
Special to World Science  

Dan­ger­ous, seem­ingly point­less stunts such as those car­ried out by young men in the “Jack­ass” se­ries of movies in­evitably in­vite mock­ery from all around—even some of the fans.

But if such feats are so sil­ly, why do young men keep at­tempt­ing such things? 

An­thro­po­l­o­gists are pro­pos­ing that risky, seem­ingly ab­surd stunts may be root­ed in ev­o­lu­tion. 

New re­search sug­gests “risk-prone in­di­vid­u­als are per­ceived as more [phys­ic­ally] for­mi­da­ble than risk-averse in­di­vid­u­als,” the sci­en­tists write in a recent re­port. This hints that such ac­ti­vi­ties may have en­hanced sta­tus among the an­ces­tors of hu­ma­ns, point­ing to a pos­si­ble ev­o­lu­tion­ary role, they add.

The re­search­ers, Dan­iel M.T. Fessler of the Uni­vers­ity of Cal­i­for­nia, Los An­ge­les and col­leagues, la­bel their point of view the “cra­zy bas­tard hy­poth­e­sis.” Fo­cus­ing on non-vi­o­lent risk-taking, they lay out their ev­i­dence in a set of stud­ies pub­lished in the Jan­u­ary is­sue of the jour­nal Ev­o­lu­tion and Hu­man Be­hav­ior.

“In Amer­i­can ver­nac­u­lar En­glish,” they wrote, “this term [cra­zy bas­tard] is ap­plied to in­di­vid­u­als, gen­er­ally young men, who in­tim­i­date ri­vals and im­press friends through vol­un­tary phys­ical risk-taking. The un­in­formed are warned not to trans­gress against a ‘cra­zy bas­tard.’”

Ev­o­lu­tion­ary the­o­ry holds that in any spe­cies, genes tend to spread through the popula­t­ion if they bol­ster an in­di­vid­u­al’s abil­ity to suc­cess­fully re­pro­duce. They spread thanks to that very re­pro­duc­tion. Genes that help an in­di­vid­ual at­tain high sta­tus would tend to en­hance that ev­o­lu­tion­ary suc­cess.

Among early humans, phys­ical risk-taking may have re­paid its costs in stat­us of­ten enough that the un­der­ly­ing genes per­sisted, sug­gest the re­search­ers, Dan­iel M.T. Fessler of the Uni­vers­ity of Cal­i­for­nia, Los An­ge­les and col­leagues. But the val­ue of risk-taking does­n’t nec­es­sarily lie in the di­rect re­sults of the act it­self, they added. It can sig­nal to by­standers that the risk-taker is a po­tent ad­ver­sary—or al­ly.

“In vi­o­lent con­flicts, in­di­vid­u­als who are in­dif­fer­ent to the pros­pect of in­ju­ry or death con­sti­tute dan­ger­ous ad­ver­sar­ies, and val­u­a­ble al­lies,” wrote the re­search­ers.

Fessler and col­leagues said they found in five stud­ies that “know­ing that a man vol­un­tarily en­gages in dan­ger­ous nonvi­o­lent ac­ti­vi­ties leads oth­ers to con­cep­tu­al­ize him as larg­er and stronger.”

Mean­while, they added, “such con­cep­tu­al­iz­a­tions are un­likely to re­flect ac­tu­al cor­rela­t­ions be­tween size/strength and phys­ical risk-proneness.”

Risky stunts may be more pop­u­lar with young peo­ple than the eld­er­ly, they added, be­cause youths en­gage in more vi­o­lence, and of­ten do so to es­tab­lish a place in their hi­er­ar­chy—a pro­cess that in an­cest­ral societies, it may have made sense to take care of ear­ly.

If the Cra­zy Bas­tard Hy­poth­e­sis is cor­rect, it makes sense to ex­pect that risk-taking is more of­ten per­formed for a male au­di­ence, Fessler and col­leagues wrote, “s­ince formidabil­ity is typ­ic­ally a great­er con­cern for the form­er. This is con­so­nant with find­ings that, among West­ern uni­vers­ity stu­dents, non­he­ro­ic phys­ical risk-taking re­duces men’s attrac­tiveness to wom­en as long-term mates, but in­creases their attrac­tiveness to men as friends.”

The idea that youths en­gage in risk-taking to gain re­spect is­n’t new, but it has­n’t been fully in­ves­t­i­gated, they added. In par­tic­u­lar, “Whether phys­ic­ally risky be­hav­ior is val­u­a­ble in part be­cause it com­mu­nicates risk-proneness re­mains un­ex­plored,” they wrote.

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Dangerous, seemingly pointless stunts such as those carried out by young men in the “Jackass” series of movies inevitably invite mockery from all around—even some of the fans. But if such feats are so silly, why do young men keep attempting such things? Anthropologists are proposing that risky, seemingly absurd stunts may be rooted in evolution. New research suggests “risk-prone individuals are perceived as more [physically] formidable than risk-averse individuals,” the scientists write in a new report. This hints that such activities may have enhanced status among the ancestors of humans, pointing to a possible evolutionary role, they add. The researchers, Daniel M.T. Fessler of the University of California, Los Angeles and colleagues, label their point of view the “crazy bastard hypothesis.” Focusing on non-violent risk-taking, they lay out their evidence in a set of studies published in the January issue of the journal Evolution and Human Behavior. “In American vernacular English,” they wrote, “this term [crazy bastard] is applied to individuals, generally young men, who intimidate rivals and impress friends through voluntary physical risk-taking. The uninformed are warned not to transgress against a ‘crazy bastard.’” Evolutionary theory holds that in any species, genes tend to spread through the population if they bolster an individual’s ability to survive and reproduce. They spread thanks to that very reproduction. Genes that help an individual attain high status would tend to enhance that evolutionary success. Evidently, physical risk-taking among early humans was worth its costs often enough that the underlying genes persisted, suggest the researchers, Daniel M.T. Fessler of the University of California, Los Angeles and colleagues. But the value of risk-taking doesn’t necessarily lie in the direct results of the act itself, they added. It can signal to bystanders that the risk-taker is a potent adversary—or ally. “In violent conflicts, individuals who are indifferent to the prospect of injury or death constitute dangerous adversaries, and valuable allies,” wrote the researchers. Fessler and colleagues said they found in five studies that “knowing that a man voluntarily engages in dangerous nonviolent activities leads others to conceptualize him as larger and stronger.” Meanwhile, they added, “such conceptualizations are unlikely to reflect actual correlations between size/strength and physical risk-proneness.” Risky stunts may be more popular with young people than the elderly, they added, because youths historically engage in more violence, and often do so to establish a place in their hierarchy—a process that it makes sense to take care of early. If the Crazy Bastard Hypothesis is correct, it makes sense to expect that risk-taking is more often performed for a male audience, Fessler and colleagues wrote, “since formidability is typically a greater concern for the former. This is consonant with findings that, among Western university students, nonheroic physical risk-taking reduces men’s attractiveness to women as long-term mates, but increases their attractiveness to men as friends.” The idea that youths engage in risk-taking to gain respect isn’t new, but it hasn’t been fully investigated, they added. In particular, “Whether physically risky behavior is valuable in part because it communicates risk-proneness remains unexplored,” they wrote.