Good question. It took me a while to think of that one. Being a new RPer a long time ago, I was experimenting in creating different characters for different types of RPs, and I happened to have a few on hand for Darwin's Soldiers.
Victor "Vic" Summers: I try keeping the names of my characters simple as possible, and my most main of characters, like Vic here, were to have a last name of either Summers, Winters, or Green. When I got the name of Victor for my char's first name, Summers was the best last name for him.
Josephine "Dr Joe" Smithson: This char I had for a while, but she had no name other than Dr Joe until Darwin's Soldiers. I needed a normal name for her, but couldn't come up with one until I remembered a not-so-used name Josephine and quickly followed up with a Smithson.
Snow: I had a wolf character with white fur and no name, and was stuck between Snow and Luna. When Darwin's Soldiers came, I decided to change her to a white German Shepherd and Snow became an easier choice.
Feral: That was inspired by Commander Feral of SWAT Katz. Almost a similar personality, but this Feral can really handle a job.
Aiko: This was also a hard name to come up with an Akita char. I wanted the name to be simple but Japanese to fit his breed. Although the name may not be truly Japanese, it sounded quite nice for his personality.
Ariol: I always have a cold-hearted hitman on hand for many RPs, and Ariol was one of his many names, besides Wraith, Gabriel, Lucias, and so on...
I'm sure that's all of my chars I've been using in Darwin's Soldiers.