A reader wrote us the following brief message: “Do worms have platelets in their blood? It’s a simple question, but I can’t seem to find the answer anywhere.” It is in fact a simple question, at least in form. However, seemingly basic questions are often hard to answer, particularly when they require a fairly advanced understanding of worm physiology. In this instance, though, we were able to find the answer with relative ease: no, worms do not have platelets in their blood.