I previously published a column called “Your Mother the Plant” in which I discussed the nearly identical structures of chlorophyll, which absorbs carbon dioxide for plants, and hemoglobin, which absorbs oxygen for animals like humans.  This striking similarity is an echo of the time long, long ago before the evolutionary divergence of plants and animals.  Hence the reference to plants being the mother of humanity.  Following this same line of reason, as I discuss below, if your mother is a plant then your sister is a mushroom.

Fungi, which include yeasts, molds, and mushrooms, are everywhere.  It’s estimated that there are approximately 1.5 millions species of fungi on earth and they live almost everywhere, including extreme environments such as the Arctic, undersea vents, and deserts.  If you follow the evolutionary tree of life, plants broke off from the stem prior to the division between animals and fungi.  As a result, fungi and animals share a number of key traits. Fungi breathe in oxygen and exhale carbon dioxide.  They get their energy by consuming food rather than through photosynthesis. Furthermore, just like humans, they are susceptible to infection by bacteria and viruses.

Fungi migrated from the oceans to the land approximately a billion years ago.  Since then they have been busily producing our soil by decomposing organic material and dissolving rocks.  The dissolution of rocks by fungi transforms minerals such as iron and calcium into compounds which can be absorbed by plants and animals. The iron we get from eating broccoli has been made available to us by fungi in the soil.  In addition, fungi living on the roots of plants are responsible for converting nitrogen from the air into compounds which can be used by plants as fertilizer.

Since fungi can be infected by viruses and bacteria just like we can, they also produce chemicals to ward off these germs.  The most famous of these chemical compounds, penicillin, was discovered in 1928 by Alexander Fleming in a contaminated Petri dish which was not washed while he was on vacation. Other molecules produced by fungi can be either poisonous or psychotropic to humans.

Humans have long utilized fungi as foods.  Yeasts are used to make beer, wine, cheese, soy sauce and other fermented products.  Mushrooms, at least most of them, can be eaten and provide unique health benefits.

I hope that this discussion of the similarity of between mushrooms and people and the unique properties of fungi will have sufficiently whet your appetite such that you come back for Part II next week, when I discuss the fungi of the future.

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