Dictyostelium discoideum
"Dictyostelium discoideum" is another species of slime mold that has many different mating types. When this organism has entered the stage of reproduction, it releases an attractant, called "acrasin". Acrasin is made up of cyclic adenosine monophosphate, or cyclic AMP. Cyclic AMP is crucial in passing hormone signals between reproductive cells. When it comes time for the cells to fuse, "Dictyostelium discoideum" has mating types of its own that dictate which cells are compatible with each other. These include NC-4, WS 582, WS 583, WS 584, WS 5-1, WS 7, WS 10, WS 11-1, WS 28-1, WS 57-6, and WS 112b. A scientific study demonstrated the compatibility of these eleven mating types of "Dictyostelium discoideum" by monitoring the formation of macrocysts. For example, WS 583 is very compatible with WS 582, but not NC-4. It was concluded that cell contact between the compatible mating types needs to occur before macrocysts can form.