No Place Like Home
The overarching irony of Planet of the Apes, of course, is that Taylor has been home the entire time. There is no more deeply ironic plot twist reveal than the sight of the head of the Statue of Liberty buried on the coastline which informs Taylor that this crazy planet of the apes he has crash landed on has the whole time been his own planet of the men.
Evolution and its Ugly Twin Brother
The other great irony of the planet of the apes (the planet as well as the movie) is that it is not just a place where apes evolved from a primitive animals to a higher state of consciousness, but a place where the human species underwent a tremendously discouraging stage of de-evolution. The irony is deepened and intensified by the fact that this regression to a more primitive state is the direct and irrefutable result of technologically advancing to the state of building weapons capable of destroying entire civilizations.
Deaf, Dumb and Blind
An ironic commentary upon science and advancement indicates that the future evolutionary stage of the apes may one day transform into one of regression as well. The leading intellectual lights of ape society are momentarily captured in replication of the iconic pictorial maxim with the proverbial saying about seeing, hearing and speaking no evil. The irony is thick: these blonde apes are not presented as Aryan scum, but seekers of knowledge and protection of the same. The tribunal they oversee reflects the famous maxim: they have shut their eyes and ears to useful new knowledge Taylor is providing them and they will be damned if they are ever hear repeating it.
The New Eve
Only one member of the spacecraft takes off from earth with Taylor is female. Only one member of the crew fails to make it to the new planet upon which they crash land alive and well: Stewart. We learn precious little about Stewart other than that Taylor rather obscenely suggests here primary purpose on the crew was to become the Eve of a new generation by making herself…available…to the male astronauts which outnumbered her. Eve dies before any begetting can begin. That’s irony!
Taylor's Question
The opening of the film features Taylor intoning like the voice of God into the ship’s computer diary a series of observations and questions that all point to his narcissistic confidence in himself as the ultimate point of human evolution. He knows there is a next step, of course; seeking something better than himself in the cosmos is what drove him personally to explore the heavens. Just before things go very, very badly, Taylor asks a rhetorical question that will turn out to be so laden with irony the answer he gets is literally broken from the pressure of the weight: “Does man, that marvel of the universe, that glorious paradox who sent me to the stars…still make war against his brother?”