The Pony is sorely lacking in anatomical information! I fear that I must homeschool him in his down time. He did not know that a gastropod, such as a snail, got its name from the words "stomach" and "foot" because it crawls along using a muscle from the area we consider the stomach. Nor that a squid and octopus are classified as cephalapods because they sport a "head-foot" body structure. I forgave him those indiscretions. He has not yet had biology, and we've run out of time to teach such concepts. At least he knew that a starfish has radial symmetry.
A heated discussion ensued as to whether a pediatrician treats children, or feet. The Pony's reasoning was that "ped" means foot, not child. Because humans are bipedal and dogs are quadrupedal, thus a pediatrician should be treating feet. Never mind that a podiatrist claims that specialty. Upon consulting my BFF Google, it turns out we were both right. PED refers to "foot" in Latin, but to "child" in Greek.
The horror arose when I told The Pony to get his fetlock off my change cup. We were cruising down the driveway in T-Hoe, and he was leaning forward from his back-seat perch to hit the garage-door opener clipped to the passenger-seat visor. "What do you mean, my fetlock? Isn't that the hair on the back of the leg?"
"What? You mean the forelock? That's the part of the mane that falls over the forehead."
"No. That is BEFORE, thus "fore" in the name. I mean on the back of the leg."
"Um. Maybe you mean feathers. Like on draft horses like the Clydesdales."
"Oh! You're talking about horses. I was talking about dogs."
"There's no name for that. Hair on the back of a dog's leg. That's about it."
"There's dew claws. That's a special name. But it's for extra toes. I wonder how come they're called dew claws?"
"Maybe because they get wet in the dew. How am I supposed to know that? I've got all that other knowledge I'm trying to share with you!"
Let the record show that upon learning about the stomach-foots and head-foots, The Pony texted his buddy to inquire as to whether he was privy to such information. Nerds have a thirst for knowledge, you know.