Comparative Anatomy means to describe anatomy by comparing different species or individuals. Concerning the mammals, much of the anatomy is very similar. Despite totally different outer appearance of the legs, the muscles present there are roughly the same, each tagged by a name from human anatomy. The inner organs tend to be a lot more different. While all animals have a digestive aparatus in the form of a long pipe, only the ruminants (cattle, buffalo, sheep, goat) have four rooms (compartments) in the stomach, viz., rumen, reticulum, omasum and abomasum.