The answer may be jealousy, if a new study is correct.

Dogs are intensely jealous creatures that experience a range of human-like emotions, the analysis found. 

The study of 1,000 pet owners in southern England uncovered cases in which jealous dogs acted as “uninvited chaperones” between couples sharing romantic moments, said the researchers, psychologist Paul Morris of the University of Portsmouth, U.K. and colleague Christine Doe.

While many pet owners may think it obvious that some animals feel jealousy, scientists demand proof of such things. Researchers generally accept that animals feel simple emotions, such as anger, anxiety and surprise, Morris and Doe said. But more complex “secondary emotions,” such as jealousy, guilt, shame and pride, are thought to be the sole province of humans and perhaps chimps.

In the study, the researchers asked pet owners to take notes of their pets’ behavior.

Dog owners showed “remarkable consistency” in reporting jealous behaviour, said Morris, an animal behaviour expert. He said dogs could feel intense pangs of jealousy and animosity when in a “love triangle” involving the owner and another person or animal.

"Long before it's in the papers"
August 03, 2010


Jilted dogs feel intense jealousy, study finds 

Aug. 22, 2006
Courtesy British Association for 
the Advancement of Science 
and World Science staff

Ever wonder why Rover keeps poking his head in the door just as you’re getting some private time with the one you love?

Dogs are intensely jealous creatures, a study has found, challenging long-held scientific beliefs. (Image courtesy City of Boston)

The an­swer may be jeal­ous­y, if a new stud­y is cor­rect.

Dogs are in­tense­ly jeal­ous crea­tures that ex­pe­ri­ence a range of human-like emo­tions, the anal­y­sis found. 

The stud­y of 1,000 pet own­ers in south­ern Eng­land un­cov­ered cases in which jeal­ous dogs acted as “un­in­vited chap­er­ones” be­tween cou­ples shar­ing ro­man­tic mo­ments, said the re­searchers, psy­chol­o­gist Paul Mor­ris of the uni­ver­si­ty of Ports­mouth, U.K. and col­league Chris­tine Doe.

While man­y pet own­ers may think it ob­vi­ous that some an­i­mals feel jeal­ous­y, sci­en­tists de­mand proof of such things. 

Re­searchers gen­er­al­ly ac­cept that an­i­mals feel sim­ple emo­tions, such as an­ger, anx­i­e­ty and sur­prise, Mor­ris and Doe said. But more com­plex “sec­ondary emo­tions,” such as jeal­ous­y, guilt, shame and pride, are thought to be the sole prov­ince of hu­mans and per­haps chimps.

In the stud­y, the re­searchers asked pet own­ers to take notes of their pets’ be­hav­ior.

Dog own­ers showed “re­mark­able con­sis­ten­cy” in re­port­ing jeal­ous be­hav­iour, said Mor­ris, an an­i­mal be­hav­iour ex­pert. He said dogs could feel in­tense pangs of jeal­ous­y and an­i­mos­i­ty when in a “love tri­an­gle” in­volv­ing the own­er and an­oth­er per­son or an­i­mal.

Jealousy, defined as a pet “pushing” between its carer and a third party, was reported in more than 80 percent of cases, Morris said. “Most academic theorists agree this behaviour is appropriately labelled as jealousy.”

The study “has convinced many scientists that dogs at least demonstrate behaviour that is very like human jealousy,” he added. “The data clearly suggest that complex emotions are present in a wider range of species than once thought and that animals do indeed have rich emotional lives.”

The research is to be presented at the British Association for the Advancement of Science Festival of Science in Norwich, U.K. on Sept. 7.

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