Animal
Animals are beings of Nature, fairly different from the humanoid races of this game. Defining them outside of game terms can be difficult, since some (such as the Bandar Log's citizens and Andramania's Calystrii) are sapient. Most have below-average 
Magic Resistance.
Animals of humanoid form (a head, a body, two hands, two feet, et cetera) leave usable 
Corpses, but the others do not. Animals eat half as many 
Supplies as non-Animals. Animals also don't benefit from the 
Champion's Skull and other 
Experience-boosting items; they don't understand human speech, or at least they don't train the same as other fellows.
Most animals in Dominions 6 are at least intelligent enough to be led around, and thus are governed by the 
Leadership score. The exceptions are considered Magic Beings, useless without 
Magic Leadership to guide them. These are easily led astray.