I was amazed when I heard that there are researchers who study the genitals of fleas. Apparently they classify them according to their shape: some form an equilateral triangle, others an isosceles triangle, and still others are flat. They can tell from these distinguishing marks whether a certain flea lives on bears in Alaska, Siberia, or Hokkaido. Their research is very interesting. In any case, it seems that the genitals of fleas are proportionately quite big. I’ll bet there are even parasitic microorganisms that live on the genitals of those fleas.
