I brought this up when I googled how these names came about. It was was from Quora. Makes some sense, I suppose.
"The terms used for assigning names to groups of animals are called 'terms of venery' in formal language. These 'terms of venery' derive from the English hunting tradition of the Late Middle Ages. This so-called 'hunting language' came to the English via the French. During this time, a specialized hunting vocabulary developed which put emphasis on sometimes even assigning different names to the same parts of different animals! "
