Zygomycetes

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          Zygomycetes (the zygote fungi) is a fungal class in the division Eumycota, according to the classification system of a taxonomist named Doyle. These fungi produce zygotes even though scientist say that there are no males or females in this kind of fungus, but only compatible + and – strains that grow together and mate with each other.

      All sexually-reproducing organisms produce zygotes sometime during their life cycle. But in zygomycete fungi such as the black bread mold, the zygote is something special. In most organisms the zygote quickly grows into an embryo. But in Zygomycetes zygotes remain encased in sturdy structures called zygosporangia for a varying length of time. These tough spore cases resist such adverse conditions as frost and drought. So while all the vegetative parts of the fungus die at the onset of winter, the zygospores remain cozy and snug in their zygosporangia till spring calls them forth to new life.

      But even then, these zygotes do not grow into embryos. Instead, they divide into four spores by a process called meiosis. Each of the spores has half as much genetic material as the zygote. The fungi that grow from these spores are called “haploid” because they have so little genetic material, while the zygote is called “diploid” because it has twice as much.

      Pilobolus is an interesting zygomycete fungus. It is the champion javelin thrower in the fungus Olympics. Pilobolus is a good father. He lives in animal dung and would like to provide his children with a better environment. So when his zygosporangia are ready to leave the paternal dung heap, he winds up like a Yankee pitcher and hurls them far away to a clean grassy region where light abounds. But alas! A horse or cow will most likely eat the blades of grass upon which the hapless zygosporangia fall. They will not suffer digestion. They are too tough. But when they pass through the digestive tract, they end up in a pile of dung, just like their parents.

      But perhaps they are lucky. Pilobolus is coprophilous, which means that dung is the nutrient upon which it feeds. So if the zygosporangia had remained attached to their cozy blades of grass, the poor creatures would die of starvation.

      So God, who created these humble zygote fungi, watches over them and provides them with everything they need to sustain their body and life.

McDaniel College: Zygomycotina Class Zygomycetes

“Biology” by Campbell, Reece, and Mitchell

“Botany: An Ecological Approach” by Jensen and Salisbury