Monkeys have thumbs.
Practically the dumbest species on the planet, next to the duck-bulled platypus, who make their dens underwater even though they breathe the air. The platypus is horribly stupid, but it is only slightly dumber than a monkey. Yet monkeys have thumbs. Those monkey-thumbs were meant for dogs. Give me my thumbs, you fucking monkeys!
The Art of Racing in the Rain, by Garth Stein
Yes, you guessed it, Enzo is indeed a dog. He’s also the narrator of the story.