Peter Porker was born a spider (simply named Peter). He resided in the basement lab of May Porker, a slightly goofy animal scientist who had created "the world's first atomic powered hairdryer," hoping that "the introduction of nuclear fusion into America's beauty salons" would "revolutionize the hair care industry". After dousing her head with water and activating the dryer, May Porker accidentally irradiated herself, and in a fit of delusion, bit Peter, who then found himself transformed into an anthropomorphic swine much like May Porker herself. Running from the Porker homestead disoriented, Peter soon came to realize that he still retained a spider's abilities:

"This is astounding! Am I a spider with the limitations of a pig? Or a pig with the proportionate strength and agility of a spider? I've become something greater than either spider or pig... I've become a Spider-Ham!" - Peter Porker, the Spectacular Spider-Ham #15 (May 1987). Go and buy the issue, it is a lot of fun!

After this startling series of events, Peter (who adopted the surname "Porker", that of his benefactor May Porker, who after the accident mentally attuned to a state in which she believed she was Peter's loving aunt) dedicated himself and his new-found abilities to fighting injustice and the occasional animal parody of established Marvel Comics villains.