Los perros pueden contagiarse del bostezo humano, lo cual sugiere que esos animales son capaces de hacer empatía con las personas, divulgó la publicación británica Biology Letters.
Pet dogs can 'catch' human yawns
Yawning is known to be contagious in humans but now scientists have shown that pet dogs can catch a yawn, too.
The copying activity suggests that canines are capable of empathising with people, say the researchers who recorded dogs' behaviour in lab tests.
Until now, only humans and their close primate relatives were thought to find yawning contagious.
The team - from Birkbeck College, University of London - reports its findings in Biology Letters.
Yawning, although sometimes a response to extreme stress, is more often a sign of tiredness; but the reason for why yawning is catching is not fully understood.
There is evidence that autistic individuals are less inclined to yawn into response to another human yawning, suggesting that contagious yawning betrays an ability to empathise, explained Birbeck's Dr Atsushi Senju.
Dr Senju and his team wondered whether dogs - that are very skilled at reading human social cues - could read the human yawn signal, and set out to test the yawning capabilities of 29 canines.
The team created two conditions, each five minutes long, in which a person - who was a stranger to the dog - was sat in front of the animal and asked to call its name. Under the first condition, the stranger yawned once the dogs had made eye contact with them.
"We gave dogs everything: visual and auditory stimulus to induce them to yawn," Dr Senju, told BBC News.
Under the second condition, the same procedure was followed, but this time the stranger opened and closed their mouth but did not yawn.
This was a precaution to ensure that dogs were not responding to an open mouth, explained Dr Senju.
The team found that 21 out of 29 dogs yawned when the stranger in front of them yawned - on average, dogs yawned 1.9 times. By contrast, no dogs yawned during the non-yawning condition.
The researchers believe that these results are the first evidence that dogs have the capacity to empathise with humans; although the team could not rule out stress-induced yawning - they hope to in future studies.
"Dogs have a very special capacity to read human communication. They respond when we point and when we signal," Dr Senju told BBC News.
The researchers explained that along with floppy ears and big soppy-eyes, humans have selected dogs to be obedient and docile. The results from this study suggest the capacity for empathy towards humans is another trait selected in dogs during domestication.
Dr Senju thinks that these traits would have been useful to humans when they began to live side-by-side with canines approximately 15,000 years ago.
Dogs catch human yawns
Article CategoryAnimal behaviour
Online DateTuesday, August 05, 2008
Ramiro M. Joly-Mascheroni1, Atsushi Senju1, Alex J. Shepherd1
1 School of Psychology, Birkbeck, University of London, Malet Street, London WC1E 7HX, UK
This study is the first to demonstrate that human yawns are possibly contagious to domestic dogs (Canis familiaris). Twenty-nine dogs observed a human yawning or making control mouth movements. Twenty-one dogs yawned when they observed a human yawning, but control mouth movements did not elicit yawning from any of them. The presence of contagious yawning in dogs suggests that this phenomenon is not specific to primate species and may indicate that dogs possess the capacity for a rudimentary form of empathy. Since yawning is known to modulate the levels of arousal, yawn contagion may help coordinate dog–human interaction and communication. Understanding the mechanism as well as the function of contagious yawning between humans and dogs requires more detailed investigation.
yawning, contagious yawning, dog, empathy, social cognition
Anderson, J.R., Myowa-Yamakoshi, M. & Matsuzawa, T. 2004 Contagious yawning in chimpanzees. Proc. R. Soc. B 271, (Suppl. 6), S468–S470, (doi:10.1098/rsbl.2004.0224).
Baenninger, R. 1987 Some comparative aspecits of yawning in Betta splendens, Homo sapiens, Panthera leo, and Papio sphinx. J. Comp. Psychol. 101, 349–354, (doi:10.1037/0735-7036.101.4.349).
Beerda, B., Schilder, M.B.H., van Hooff, J.A.R.A.M., de Vries, H.W. & Mol, J.A. 1998 Behavioural, saliva cortisol and heart rate responses to different types of stimuli in dogs. Appl. Anim. Behav. Sci. 58, 365–381, (doi:10.1016/S0168-1591(97)00145-7).
Daquin, G., Micallef, J. & Blin, O. 2001 Yawning. Sleep Med. Rev. 5, 299–312, (doi:10.1053/smrv.2001.0175).
Deputte, B.L. 1994 Ethological study of yawning in primates. 1. Quantitative analysis and study of causation in 2 species of Old World monkeys (Cercocebus albigena and Macaca fascicularis). Ethology 98, 221–245.
Diederich, C. & Giffroy, J.-M. 2006 Behavioural testing in dogs: a review of methodology in search for standardisation. Appl. Anim. Behav. Sci. 97, 51–72, (doi:10.1016/j.applanim.2005.11.018).
Hare, B. & Tomasello, M. 2005 Human-like social skills in dogs?. Trends Cogn. Sci. 9, 439–444, (doi:10.1016/j.tics.2005.07.003).
Hare, B., Brown, M., Williamson, C. & Tomasello, M. 2002 The domestication of social cognition in dogs. Science 298, 1634–1636, (doi:10.1126/science.1072702).
Heyes, C.M. & Ray, E.D. 2000 What is the significance of imitation in animals?. Adv. Study Behav. 29, 215–245, (doi:10.1016/S0065-3454(08)60106-0).
Hennessy, M.B., Morris, A. & Linden, F. 2006 Evaluation of the effects of a socialization program in a prison on behavior and pituitary-adrenal hormone levels of shelter dogs. Appl. Anim. Behav. Sci. 99, 157–171, (doi:10.1016/j.applanim.2005.09.011).
Heusner, A.P. 1946 Yawning and associated phenomena. Physiol. Rev. 26, 156–168.
McNemar, Q. 1947 Note on the sampling error of the difference between correlated proportions or percentages. Psychometrika 12, 153–157, (doi:10.1007/BF02295996).
Miklósi, Á. & Soproni, K. 2006 A comparative analysis of animals' understanding of the human pointing gesture. Anim. Cogn. 9, 81–93, (doi:10.1007/s10071-005-0008-1).
Miklósi, Á., Kubinyi, E., Topál, J., Gácsi, M., Virányi, Z. & Csányi, V. 2003 A simple reason for a big difference: wolves do not look back at humans, but dogs do. Curr. Biol. 13, 763–766, (doi:10.1016/S0960-9822(03)00263-X).
Miklósi, Á., Topál, J. & Csányi, V. 2007 Big thoughts in small brains? Dogs as a model for understanding human social cognition. Neuroreport 18, 467–471, (doi:10.1097/WNR.0b013e3280287aae).
Moore, J.E. 1942 Some psychological aspects of yawning. J. Gen. Psychiatry 27, 289–294.
Paukner, A. & Anderson, J.R. 2006 Video-induced yawning in stumptail macaques (Macaca arctoides). Biol. Lett. 2, 36–38, (doi:10.1098/rsbl.2005.0411).
Platek, S.M., Critton, S.R., Myers, T.E. & Gallup, G.G. 2003 The role of self-awareness and mental state attribution. Cogn. Brain Res. 17, 223–227, (doi:10.1016/S0926-6410(03)00109-5).
Preston, S.D. & de Waal, F.B. 2002 Empathy: Its ultimate and proximate bases. Behav. Brain Sci. 25, 1–20, (doi:10.1017/S0140525X02000018).
Provine, R.R. 1986 Yawning as a stereotyped action pattern and releasing stimulus. Ethology 72, 448–455.
Rooney, N.J., Gaines, S.A. & Bradshaw, J.W.S. 2007 Behavioural and glucocorticoid responses of dogs (Canis familiaris) to kennelling: investigating mitigation of stress by prior habituation. Physiol. Behav. 92, 847–854, (doi:10.1016/j.physbeh.2007.06.011).
Senju, A., Maeda, M., Kikuchi, Y., Hasegawa, T., Tojo, Y. & Osanai, H. 2007 Absence of contagious yawning in children with autism spectrum disorder. Biol. Lett. 3, 706–708, (doi:10.1098/rsbl.2007.0337).
Smith, E. 1999 Yawning: an evolutionary perspective. Hum. Evol. 14, 191–198, (doi:10.1007/BF02440156).
Topál, J., Byrne, R., Miklósi, Á. & Csányi, V. 2006 Reproducing human actions and action sequences: "Do as I do!" in a dog. Anim. Cogn. 9, 355–367, (doi:10.1007/s10071-006-0051-6).
Virányi, Z., Topál, J., Miklósi, Á. & Csányi, V. 2006 A nonverbal test of knowledge attribution: a comparative study on dogs and children. Anim. Cogn. 9, 13–26, (doi:10.1007/s10071-005-0257-z).