"Long before it's in the papers"
January 28, 2015

RETURN TO THE WORLD SCIENCE HOME PAGE


Cats are crafty manipulators, study finds

July 13, 2009
Courtesy Cell Press
and World Science staff

An­y­one who has had cats knows how hard it can be to get them to do an­y­thing they don't want to do. 

But house cats them­selves seem to have dis­tinctly less trou­ble get­ting hu­mans to do their bid­ding, ac­cord­ing to a re­port pub­lished in the July 14 is­sue of the re­search jour­nal Cur­rent Bi­ol­o­gy.

A study suggests cats  mo­ti­vate peo­ple to fill their food dishes by send­ing some­thing of a mixed sig­nal: an ur­gent cry or me­ow­ing sound em­bed­ded with­in an oth­er­wise pleas­ant purr, sci­en­tists say. The re­sult: a call that hu­mans may find an­noy­ingly hard to ig­nore. (Im­age cour­tesy U.S. NHGRI)


The crafty fe­lines mo­ti­vate peo­ple to fill their food dishes by send­ing some­thing of a mixed sig­nal: an ur­gent cry or me­ow­ing sound em­bed­ded with­in an oth­er­wise pleas­ant purr, sci­en­tists say. The re­sult is a call that hu­mans gen­er­ally find an­noy­ingly hard to ig­nore.

“The em­bed­ding of a cry with­in a call that we nor­mally as­so­ci­ate with con­tent­ment is quite a sub­tle means of elic­it­ing a re­spon­se,” said Ka­ren Mc­Comb of the Un­ivers­ity of Sus­sex, U.K. “So­licita­t­ion purring is prob­ab­ly more ac­cept­a­ble to hu­mans than overt me­ow­ing, which is likely to get cats ejected from the bed­room.” 

She sug­gests that this form of cat com­mu­nica­t­ion sends a sub­lim­i­nal sort of mes­sage, tap­ping in­to an in­her­ent sen­si­ti­vity that hu­mans and oth­er mam­mals have to cues rel­e­vant in the con­text of nur­tur­ing their off­spring.

Mc­Comb said she was in­spired to the research by her own cat, who con­sist­ently wakes her up in the morn­ings with a very in­sist­ent purr. She learn­ed in talk­ing with oth­er cat own­ers that some of their cats too had mas­tered the same ma­ni­pu­la­tive trick. As a sci­ent­ist who al­ready stud­ied vo­cal com­mu­nica­t­ion in mam­mals, from ele­phants to li­ons, she de­cid­ed to get to the bot­tom of it. 

It turned out that was­n't so easy to do. The cats were per­fectly will­ing to use their co­er­cive cries in pri­vate, but when strangers came around they tended to clam up. Her team there­fore had to train cat own­ers to rec­ord their own cats’ cries.

In a se­ries of play­back ex­pe­ri­ments with those calls, they found that hu­mans judged the purrs rec­orded while cats were ac­tively seek­ing food as more ur­gent and less pleas­ant than those made in oth­er con­texts, even if they had nev­er had a cat.

“The cru­cial fac­tor de­ter­min­ing the ur­gen­cy and pleas­antness rat­ings that purrs re­ceived was an un­usu­al high-fre­quen­cy el­e­ment—rem­i­nis­cent of a cry or me­ow—em­bed­ded with­in the nat­u­rally low-pitched purr,” Mc­Comb said. “Hu­man par­ti­ci­pants in our ex­pe­ri­ments judged purrs with high lev­els of this el­e­ment to be par­tic­u­larly ur­gent and un­pleas­ant.” When the team re-synth­esised the rec­orded purrs to re­move the em­bed­ded cry, leav­ing all else un­changed, the ur­gen­cy rat­ings for those calls de­creased sig­nif­i­cantly.

Mc­Comb said she thinks this cry oc­curs at a low lev­el in cats’ nor­mal purring, but “cats learn to dra­mat­ic­ally ex­ag­ger­ate it when it proves ef­fec­tive in gen­er­at­ing a re­sponse from hu­mans.” In fact, not all cats use this form of purring at all, she said, not­ing that it seems to most of­ten de­vel­op in cats that have a one-on-one rela­t­ion­ship with their own­ers rath­er than those liv­ing in large house­holds, where their purrs might get over­looked by un­fa­mil­iar peo­ple.

In those cases, she said, cats seem to find it more ef­fec­tive to stick to the stand­ard me­ow.


* * *

Send us a comment on this story, or send it to a friend









 

Sign up for
e-newsletter
   
 
subscribe
 
cancel

On Home Page         

LATEST

  • St­ar found to have lit­tle plan­ets over twice as old as our own

  • “Kind­ness curricu­lum” may bo­ost suc­cess in pre­schoolers

EXCLUSIVES

  • Smart­er mice with a “hum­anized” gene?

  • Was black­mail essen­tial for marr­iage to evolve?

  • Plu­to has even cold­er “twin” of sim­ilar size, studies find

  • Could simple an­ger have taught people to coop­erate?

MORE NEWS

  • F­rog said to de­scribe its home through song

  • Even r­ats will lend a help­ing paw: study

  • D­rug may undo aging-assoc­iated brain changes in ani­mals

Anyone who has ever had cats knows how hard it can be to get them to do anything they don't want to do. But house cats themselves seem to have distinctly less trouble getting humans to do their bidding, according to a report published in the July 14 issue of the research journal Current Biology. The crafty felines motivate people to fill their food dishes by sending something of a mixed signal: an urgent cry or meowing sound embedded within an otherwise pleasant purr, scientists say. The result is a call that humans generally find annoyingly hard to ignore. “The embedding of a cry within a call that we normally associate with contentment is quite a subtle means of eliciting a response,“ said Karen McComb of the University of Sussex. “Solicitation purring is probably more acceptable to humans than overt meowing, which is likely to get cats ejected from the bedroom.“ She suggests that this form of cat communication sends a subliminal sort of message, tapping into an inherent sensitivity that humans and other mammals have to cues relevant in the context of nurturing their offspring. McComb said that she was inspired by her own cat, who consistently wakes her up in the mornings with a very insistent purr. She learned in talking with other cat owners that some of their cats too had mastered the same manipulative trick. As a scientist who already studied vocal communication in mammals, from elephants to lions, she decided to get to the bottom of it. It turned out that wasn't so easy to do. The cats were perfectly willing to use their coercive cries in private, but when strangers came around they tended to clam up. Her team therefore had to train cat owners to record their own cats' cries. In a series of playback experiments with those calls, they found that humans judged the purrs recorded while cats were actively seeking food as more urgent and less pleasant than those made in other contexts, even if they had never had a cat themselves. “The crucial factor determining the urgency and pleasantness ratings that purrs received was an unusual high-frequency element—reminiscent of a cry or meow—embedded within the naturally low-pitched purr,“ McComb said. “Human participants in our experiments judged purrs with high levels of this element to be particularly urgent and unpleasant.“ When the team re-synthesised the recorded purrs to remove the embedded cry, leaving all else unchanged, the urgency ratings for those calls decreased significantly. McComb said she thinks this cry occurs at a low level in cats' normal purring, “but we think that cats learn to dramatically exaggerate it when it proves effective in generating a response from humans.“ In fact, not all cats use this form of purring at all, she said, noting that it seems to most often develop in cats that have a one-on-one relationship with their owners rather than those living in large households, where their purrs might get overlooked by unfamiliar people. In those instances, she said, cats seem to find it more effective to stick to the standard meow.