If a dog has eyes that seem to be telling you something or demanding your attention, it could be evolution's way of manipulating your feelings.
如果狗狗的眼睛似乎在向你诉说，或恳求关注，这可能是它们进化出来控制你情绪的方式。
Researchers have found that dogs have evolved muscles around their eyes, which allow them to make expressions that particularly appeal to humans.
研究人员发现，狗的眼周肌肉已经进化到能够让它们做出特别吸引人类的表情。
A small facial muscle allows dog eyes to mimic an "infant-like" expression which prompts a "nurturing response".
狗的眼部有一小块肌肉，可以让狗狗的眼睛模仿“婴儿般的”表情，从而激发人类的“养育反应”。
The study says such "puppy eyes" helped domesticated dogs to bond with humans.
研究称，这种“小狗眼”有助于宠物狗与人类建立情感纽带。
Previous studies have shown how such canine expressions can appeal to humans, but this research from the UK and US shows there has been an anatomical change around dogs' eyes to make it possible.
此前的研究已证实，狗狗的这种表情是如何吸引人类的，但这项英美两国的共同研究表明，这是由于狗狗眼睛周围的解剖结构发生了变化。
This allows dogs to create what the researchers call "expressive eyebrows" and to "create the illusion of human-like communication".
这使得狗狗能够展现出研究人员所说的“表情眉”， 由此“营造出与人类相似的交流沟通假象”。

"When dogs make the movement, it seems to elicit a strong desire in humans to look after them," says the study, co-authored by Dr Juliane Kaminski at the University of Portsmouth.
研究报告称，“当狗做这个动作时，似乎会引起人类想要照顾它们的强烈渴望。”朴茨茅斯大学的朱妮娜·卡明斯基博士参与了研究报告的撰写。
This muscle movement allows dogs' eyes to "appear larger, more infant-like and also resembles a movement humans produce when they are sad".
这种肌肉运动使狗狗的眼睛“看起来更大，更像婴儿，也能展现出类似于人类的悲伤表情”。
She says that humans would have an "unconscious preference" to protect and breed from dogs with such an appealing trait, giving them an evolutionary advantage and reinforcing this change in subsequent generations.
朱妮娜·卡明斯基博士说，人类会有一种“无意识的偏好”来保护和养育具有这种吸引人的特性的狗狗，使它们具有进化优势，并在繁衍过程中不断得到强化。
"The evidence is compelling that dogs developed a muscle to raise the inner eyebrow after they were domesticated from wolves," says Dr Kaminski, in a study published in the Proceedings of the National Academy of Sciences of the USA.
卡明斯基博士在发表于《美国国家科学院院刊》上的一项研究中表示:“有令人信服的证据表明，狗在从狼驯化后，发育出了一种可以抬高眉毛内测的肌肉。”
The findings, from UK and US researchers in anatomy and comparative psychology, show that the facial change has developed over thousands of years of dogs living alongside humans.
英国和美国的解剖学和比较心理学研究人员的研究结果表明，这种面部变化是在狗和人类生活在一起的数千年里形成的。
Previous research has shown that dogs are more likely to use this "puppy eyes" expression when a human is looking at them - suggesting that it is a deliberate behavior and intended for human consumption.
此前的研究表明，当人类注视着狗狗时，狗狗更有可能使用这种“小狗眼”的表情，这表明这是有意而为，就是做给人看的。
Anatomist and report co-author, Professor Anne Burrows of Duquesne University in the US, says that in evolutionary terms the changes to dogs' facial muscles was "remarkably fast" and could be "directly linked to dogs' enhanced social interaction with humans".
该研究报告的合著者、解剖学家、美国杜肯大学教授安妮·巴罗斯说，从进化角度看，狗面部肌肉的变化“非常快”，可能“和狗与人类互动密切直接相关”。
The findings, says Professor Bridget Waller of the University of Portsmouth, show "how important faces can be in capturing our attention, and how powerful facial expression can be in social interaction".
朴茨茅斯大学布里奇特·沃勒教授表示，这些发现表明，“面部表情在吸引我们的注意力方面有多么重要，在社交互动中有多么强大”。