There's an incongruity between animal and human anatomy. In humans, dorsal does indeed mean back, not top. Wikipedia has a wall of text by way of explanation:

There's an incongruity between animal and human anatomy. In humans, dorsal does indeed mean back, not top. Wikipedia has a wall of text by way of explanation: http://en.wikipedia.org/wiki/Anatomical_terms_of_location#Why_zootomy_and_androtomy_terms_differ http://en.wikipedia.org/wiki/Anatomical_terms_of_location#Wh...