Jake, as his last name implies, is a spider monkey who quickly became Adam's best friend. He is often very possessive of Adam and hates not having him around regularly. Jake is emotional and goofy who takes to heart some of Adam's comments and actions, leading to some overly dramatic and exaggerated reactions. He can be lazy and selfish, but at the same time he is also fairly sensible. A running gag in the series is his obsession with the well-being of his butt, which he made grow so large that it blocked out the sun in one episode. Along with the majority of the other animal students, Jake lives close enough to the school that he can see it from where he lives. Jake seems to be very unintelligent. An example of his unintelligence is that once he believed that there was an aquatic animal named the "mer-monkey". When he finally "found it", it was actually a fishing lure. But he just said, "Oh, well. Nobody's perfect." Jake is voiced by Tom Kenny.