IF you're Happy and you know it, pat your head. That is how a 34-year-old female Asian elephant in the Bronx Zoo showed researchers that pachyderms can recognize themselves in a mirror - complex behaviour observed in only a few other species.　　The test results suggest elephants - or at least Happy - are self-aware. The ability to distinguish oneself from others had been shown only in humans, chimpanzees and, to a limited extent, dolphins.　　That self-recognition may underlie the social complexity seen in elephants, and could be linked to the empathy and altruism that the big-brained animals have been known to display, said researcher Diana Reiss, of the Wildlife Conservation Society.　　In a 2005 experiment, Happy faced her reflection in an 8-by-8-foot mirror and repeatedly used her trunk to touch an "X" painted above her eye. The elephant could not have seen the mark except in her reflection.　　That divergent species such as elephants and dolphins should share the ability to recognize themselves as distinct from others suggests the characteristic evolved independently, according to the study.　　　　如果你知道你是“快乐”，拍一下脑袋吧！这就是布朗克斯动物园中34岁的亚洲雌象“快乐”向研究者们展示厚皮类动物能在镜子中认出自己的方式。这种复杂行为仅在少数几个物种身上能观察到。　　实验结果显示，大象——至少“快乐”—— 有自我认知能力。目前，只有人类和黑猩猩具备这种能将自己与其他动物区分开的能力。另外，海豚也在某种程度上具备这种能力。　　野生动物保护协会研究员黛安娜赖斯表示，大象的自我认知能力为它们社会行为的复杂性提供了解释依据。此外，自我意识还与这些大脑发达的动物所表现出的移情能力和利他主义行为有关。　　在2005年的实验中，“快乐”在一面8x8英尺的镜子中看到自己的映像，不断地用象鼻触摸实验人员画在她眼睛上方的“X”记号。如果“快乐”看不到自己镜中的映像，她是不可能看到这个记号的。　　研究显示，像大象和海豚这些分属不同物种的动物竟然具备相同的自我认知能力，这表明该特征是能够独立进化的。