It's almost as if they understand that the mouth and the eyes are the most significant bit of the human face.
就好像它们知道嘴和眼睛是人类面部最重要的部位。
英语百科
Most significant bit
In computing, the most significant bit (MSB, also called the high-order bit) is the bit position in a binary number having the greatest value. The MSB is sometimes referred to as the left-most bit due to the convention in positional notation of writing more significant digits further to the left.