Professor Zygote was a mad scientist who created dinosaurs in his laboratory, appearing in the playset Mighty Max Blows Up Dino Lab. After Max released all his creations, he angrily tried to destroy Max with a laser but instead blew up his lab with it.
He appeared, reimagined somewhat, in the episode Zygote's Rhythm. He had created a ray that could advance or regress any creature's place in the evolutionary scale, and used it to turn Max's pet Thor into a dinosaur and Virgil into a pterodactyl. After the pair of them defeated his Mutasaurus, a mutant creature composed of the major features of various species of dinosaur, Zygote turned the ray on himself and evolved into an ultra-intelligent futuristic form. However, by evolving himself so quickly he become confused and unable to make use of his new intelligence, accidentally firing his evolution ray into the volcano under his headquarters, destroying it. As the episode ended he was seen floating away, in command of his new gifts.
Zygote reappeared in Zygote Music where he kidnapped a boy with futuristic mental powers with the intent of studying them. He evolved even further in this episode (including into a fowl-like form similar to Virgil's race) until he became a being of pure thought and left the physical realm forever.