Edward Whelan, later known as Vermin, was a geneticist for Oscorp Industries.
The Vermin was created entirely by accident, and with the noblest intentions.
Filling the role of professional confidant to Curt Connors since the abrupt departure of Richard Parker, Oscorp-geneticist Edward Whelan kept a watchful eye on his colleague's cross-species research. Whelan's initial wonder and amazement gradually matured to doubt and even fear, as he pondered the possible horrific potential of Connors' discoveries.
Soon enough, Whelan’s fears came to life in the form of the Lizard – and Whelan took it upon himself to find a cure to save his friend. Sequestered in his office for days, Whelan didn’t sleep for more than ninety hours, choosing not to rest until he had produced what he believed to be an antidote (which itself included the DNA of the only human around – himself). Wanting to know for sure that the antidote was safe to organic beings, Whelan injected it into a lab rat – then collapsed in his office out of sheer exhaustion. Sadly, pure mental fatigue caused Whelan’s calculations and measurements to be wrong.
As Whelan slept the deepest sleep of his life, the injected lab rat began to grow in size. Within an hour, it was the size of a human, even adopting a newly instinctive bipedal mode of locomotion. And it was hungry. Nearby, the humanoid rat took a bite out of the closest food available – Edward Whelan.
Whelan screamed loudly, now very much awake and in great pain. “You Vermin!” The ruckus summoned Oscorp security, who subdued the beast and quarantined it.
It was in the hospital, as his body began to change, that Whelan realized his greatest error. Fur surfaced from his pours. Claws emerged from his fingers. He was becoming a rat-like monstrosity himself. As his brain faded to mush, shortly before his instincts led him to a new home in the sewers, he recognized his mistake: “I didn’t create an antidote… I created a virus…”.
When Peter Parker snuck into Oscorp, with the help of Gwen Stacy, Vermin very quickly detected his radioactive blood, and took a particular disliking to him. When Scorpion broke out, he freed Vermin and the other cross-species mutations. Right from the start, Vermin became one of the biggest causes of an infection, which would spread throughout New York. He attacked Gwen Stacy and bit her, infecting her, which only fueled Peter's quest for a cure.
Spider-Man later chased Vermin through a sewer, in an attempt to deliver a DNA sample to Connors. The Vermin escaped from the first battle when a group of S-Bots interfered. Spider-Man tracked him down again, this time not only getting a sample, but defeating him for good.
- While visiting the home of Kraven the Hunter Peter is shown a room full of his latest trophies. These trophies turn out to be Scorpion, Iguana and Nattie; cross-species Peter had battled before. Vermin and Rhino however are the only cross-species not shown to be stuffed and mounted in Kraven's trophy room. Where they could be after surviving Kraven's hunt is unknown but they might have survived because they were humans injected with animal serum.