8 (ish)
Answer: 8 mathematicians (and two computer geeks). Thanks to Abby, Stefan, Mike, Laura, Ben, Molly, and Amanda (and Nick and Tim–my husband extraordinaire) for your help this weekend!
Brown Sharpie
Mathematical Cartoons inspired by Sharpie Fumes
Uh, thanks, but calling someone in math-bio a mathematician is like calling a pescoterian a vegetarian. You can pretend it is the same, but it is not nearly as hardcore.