I had an anti-Semitic iguana, very embarrassing around Hanukkah.
I don’t remember ever seeing something like that. I’m sure it’s happened but aside from growling in a way that says: “Get away from me/the fuck you want huh?!” I haven’t seen them try to command humans like that.
I have two dogs who are somewhat opposite in their reactions towards others. One dog, a medium sized pinscher mix, loves people, regardless of who the person is, but doesn’t like other dogs except our other one. The other dog, a min pin, likes all other dogs but won’t tolerate people she doesn’t know. I have no idea why they ended up like this 
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A friend of mine had a huge, beautiful iguana. I stopped by to visit him once, along with a woman I was dating. I had interacted with the iguana before, and he was always very cool and laid back.
The minute the woman I was with walk d into the room, the iguana went nuts, doing all sorts of aggressive behaviors. My friend asked if she was menstruating, which initially pissed her off, but it turns out she was. Turns out male iguanas can detect pheromones from a female human that are similar to those of a female iguana. Cite
Doesn’t need growling at all. My Weim did it like this…
She liked having her tennis ball thrown. Or otherwise moved, if I wouldn’t do it, she’d spit it out with a flick of her head at a wall and chase the rebound. Bonus points for an unexpected carom.
Anyway, sometimes I threw the ball too far for her to want to run. Large-breasted women, on the other hand, usually wouldn’t. Ergo, at dog park or dog bar, occassionally she’d walk up to such a woman, drop the ball near her, and stare at the ball. Then stare at the woman, look over her front shoulder, back at the person, then to the ball. Repeat if the human is slow, occasionally with a paw flick to get the ball closer to the human. Then back away in a ready crouch.
“Oh, does she want me to throw this?”
“I’m terribly sorry about this. Is my dog bothering you?”
“No. She’s beautiful. Can I throw this anywhere?” And so on.
Hilarious. I offered so many times to my single male friends to borrow her as a wingman.
But the point is, she did it once, didn’t get rebuffed and it worked out for the dog, so then it became a routine. Whatever factors the first strange woman had, the dog tried to find in subsequent ball throwing draftees. (She didn’t go for less-endowed women after an unfortunate attempt with a collegiate softball player. Outfielder too, judging by how far she threw that tennis ball. I swear I could hear canine cursing the entire lengthy trip out to the where the ball ended up…)
Border collies and other highly motivated herding breeds can do a similar sort of thing. They can herd people just by gestures, glares, and body position—no nipping or growling required. And, magically, all of the people in a room are huddled up at one side of it, or all of the little kids at a soccer practice are together near the goal.
Non-verbal communication to things the dog perceives as being receptive, because this is how it worked in the past with this kind of thing.