Mouse Deer: Smallest Hoofed Mammal! 

The Chihuahuas of the deer world.

Don't call them deer, the word "deer" refers exclusively to the family Cervidae, the biggest required trait that makes a deer a deer is the possession of antlers, hence the reason why deer belong to the infraorder Pecora, which includes all members of the suborder Selenodontia that possess cranial weaponry, so it is now incorrect to refer those of the taxa Tragulidae, Hydropotes, and Moschus as deer, with them being referred to as "mouse deer", "water deer", and "musk deer" respectively, where their correct names are actually "chevrotain", "yoyong", and "kasturi" respectively, in fact, chevrotains (family Tragulidae), yoyongs (genus Hydropotes), and kasturis (genus Moschus) are not deer at all, nor are they closely related to them, kasturis and yoyongs are the only extant genera of the respective families Moschidae and Hydropotidae, both these families constitute the superfamily Moschoidea, chevrotains (family Tragulidae) are the only surviving family of both the superfamily Traguloidea and the infraorder Tragulina, whereas the superfamily Moschoidea that contains the monotypic families Hydropotidae and Moschidae is the only extant taxon of the infraorder Vampyrodonta, this officially means that true deer are more closely related to bovids, giraffes, okapis, and pronghorns than any of them are to either kasturis, yoyongs, or chevrotains, as well as bovids, deer, giraffes, okapis, and pronghorns all being more closely related to camels than they are to kasturis, yoyongs, and chevrotains, this is because the camels (family Camelidae) that are the only extant family of both the superfamily Cameloidea and the infraorder Tylopoda are the most derived of the Selenodontia suborder, they're one of the only two families of hoofed mammals to have plantigrade feet, in fact, Pecora and Tylopoda are each other's closest relatives, while both Tragulina and Vampyrodonta are considered basal offshoots of the Selenodontia suborder.

i would’ve called it a deer rat.

When I hear evolution being used as though it is some kind of proven fact, I begin to shut down as now I'm listening to an idiot.