So much fail. It's like Ang Lee's Hulk all over again, but instead of Hulk-dogs it's apes.
Also, they already explained the origin as a paradox of time travel in Escape and Conquest. Cornelius and Zira get in Bright Eyes' spaceship, get caught in some kind of quantum deus ex machina ray, and wind up back in the 70s. Hijinks, adventure, and social statements ensue - and they secretly give birth to Cesar, who leads the ape revolution. (He also subsequently fucks up the space-time continuum because studio execs panicked over the idea of African Americans rising up in violent revolution because of the speech at the end.)
Anyway, it looks like someone smeared ape shit all over a forgotten Spiderman 3 subplot.