科學(xué)家發(fā)現(xiàn)，狗能感到一種簡單形式的嫉妒。對不同物種的實驗表明當(dāng)一只猴子的伙伴因為執(zhí)行完全一樣的任務(wù)卻接受了更多獎賞的時候,，它常常表達(dá)出怨恨的行為,。猴子表現(xiàn)出進行罷工,、拒絕參與以及忽略它們所認(rèn)為的較低級別的補償,。
Friederike Range及其同事報告說，狗也具有類似的辨別能力,，盡管敏感度較低,。這組科學(xué)家對由其主人陪同的一對家養(yǎng)的狗進行了實驗。受試狗和它的伙伴相鄰坐著,，而它們的主人站在它們的身后,，每一只狗被提示把爪子放在實驗者的手上，如果它這樣照辦了,，它將會得到一片香腸或者面包,。和多種對照情況相比，這些狗對于不公平的獎賞分配的反應(yīng)不同,，這是根據(jù)當(dāng)受試狗的伙伴因為完成任務(wù)而獲得食物但受試狗沒有得到食物時的反應(yīng)而衡量的,。這種怨恨可以用實驗者提示狗的次數(shù)或者狗在拒絕之前執(zhí)行任務(wù)的次數(shù)量化。這些狗看上去并不關(guān)心究竟它們得到了什么獎賞,，也不關(guān)心伙伴在收到食物前是否完成了任務(wù),。這組科學(xué)家說，狗的嫉妒可能是更復(fù)雜的靈長類感情的進化前驅(qū),。（生物谷Bioon.com）
生物谷推薦原始出處：
PNAS December 8, 2008, doi: 10.1073/pnas.0810957105
The absence of reward induces inequity aversion in dogs
Friederike Rangea,b,1, Lisa Horna, Zsófia Viranyib,c, and Ludwig Hubera
aDepartment of Neurobiology and Cognition Research, University of Vienna, A-1091 Wien, Austria;
cKonrad Lorenz Institute for Evolution and Cognition Research, A-3422 Altenberg, Austria; and
bWolf Science Center, 4645 Grünau, Austria
Abstract
One crucial element for the evolution of cooperation may be the sensitivity to others' efforts and payoffs compared with one's own costs and gains. Inequity aversion is thought to be the driving force behind unselfish motivated punishment in humans constituting a powerful device for the enforcement of cooperation. Recent research indicates that non-human primates refuse to participate in cooperative problem-solving tasks if they witness a conspecific obtaining a more attractive reward for the same effort. However, little is known about non-primate species, although inequity aversion may also be expected in other cooperative species. Here, we investigated whether domestic dogs show sensitivity toward the inequity of rewards received for giving the paw to an experimenter on command in pairs of dogs. We found differences in dogs tested without food reward in the presence of a rewarded partner compared with both a baseline condition (both partners rewarded) and an asocial control situation (no reward, no partner), indicating that the presence of a rewarded partner matters. Furthermore, we showed that it was not the presence of the second dog but the fact that the partner received the food that was responsible for the change in the subjects' behavior. In contrast to primate studies, dogs did not react to differences in the quality of food or effort. Our results suggest that species other than primates show at least a primitive version of inequity aversion, which may be a precursor of a more sophisticated sensitivity to efforts and payoffs of joint interactions.
