Dogs are able to tell how big another dog is just by listening to its growl, a new study has found.Scientists from the E tv s Loránd University in Budapest, Hungary, were testing the dogs using a specific growl used by dogs to protect their food.

　　一项最新研究发现，狗能够通过犬吠来辨别出另一只狗的大小。来自匈牙利首都布达佩斯罗兰大学的科学家们进行此项研究，他们把狗保护食物时所发出的叫声放给试验中的狗听，来观察它们的反应。

They showed one group of 24 dogs two images projected onto a screen, one of a large dog, the other a small one. The dogs were then played the recording of growl from either small or large dog which came from between the two images.

　研究人员首先在屏幕上向一组（24只）狗放映大小不同的两只狗的图片，然后将图片中大狗或者小狗的叫声录音放给这些狗听。

　　The results showed that 20 of the 24 test dogs looked at the image of the appropriate-sized dog first and looked at it longest.　A control group of 24 dogs were also played the dog growls but were instead shown silhouettes of large and small cats or geometric shapes.

　　结果显示，有20只狗都先向正确的实验对象望去，并且观望的时间较长。科学家给参照组24只狗放映大小不等的猫或几何形状的阴影图片以代替原来狗的图片，并同时播放狗叫声。

　　Most of the dogs in this group looked first at the image on the left, a finding that supports earlier studies that have found dogs tend to look to the left when presented with something unexpected.

　　这一组大部分的狗都看左边的图片，这一发现支持狗看到意想不到的事物时，倾向于向左看的早期研究发现。