kesäkuu 1, 2023

Fungi

Note: Rough Draft Report for a lower level English course I'm taking. I realized a little ways into it, that the scope of the paper was too large for the page requirements, so I just ended up hitting interesting points.

Abstract
Fungi are a diverse and enduring phylogenetic kingdom. Researchers estimate that fungi separated from animals 900 million to 1 billion years ago. During this time they have diversified, and colonized many new ecological niches. It is estimated that there are roughly 1.5-13.2 million different species of fungi. As such it is important to understand how they are classified, what role they play in global ecology. Fungi also have an interesting and long cultural and religious intersection with humanity, and play an important medicinal and economic role in modern society.
Keywords: Fungi, Fungal Ecology, Fungal Cultivation

Fungi
Fungi are a diverse group of organisms belonging to the same arbitrary phylogenetic kingdom. Up until the last century fungi were considered to be phylogenetically part of the plant kingdom. Many people will recognize fungi as organisms that produce the mushrooms they see in their yards, or when they venture into the woods. To the casual observer they are ephemeral, appearing for moments at a time before decaying. But underneath the soil, inside of insects, plants, and practically every form of life living or dead lies a fungi, whether it be as a spore, or an extensive mycelial network. They play an important role in many aspects of ecological and various chemical cycles. The organisms we know as fungi are estimated to have separated from animals some 900 million to 1 billion years ago (Webster & Weber, 2007) . Over this time it is estimated that they have diverged into roughly 1.5 million species. Of which 80,000 to 120,000 have been described to date (Webster & Weber, 2007) .

What Are Fungi
There is some argument over the taxonomy of fungi. “The fungal kingdom is now recognized as one of the oldest and largest clades of living organisms on earth” (D. Moore, G.D Robson, A.P.J Trinci, 2020, p.24). It is comprised of 10 phyla, consisting of Cryptomycota, Microsporidia, Chrytidiomycota, Monoblepharidomycota, Neocallimstigomycota, Blastocladiomycota, Zoopagomycota, Mucoromycota, Asocomycota, and Basidiomycota. According to J. Webster and R.W.S Weber fungi are defined by 11 properties which are modified from the work of G.C Ainsworth. They are heterotrophs, incapable of photosynthesis, and unlike animals they do not ingest their food. Instead they feed by excreting enzymes which break down a variety of types of matter and absorb the nutrients through their cell wall. Fungi also have a vegetative state that is not often seen by casual observers. This vegetative state typically occurs inside of a host or substratum as a non-motile mycelium of hyphae. But there are many exceptions to this, including yeast cells as seen in Figure 1.
Cell walls are also another property of fungi, typically made of chitin or glucans, but again due to the large number of species there are many exceptions. Fungi are also eukaryotic meaning the cells have one or more nuclei. The life cycle of fungi can be simple, or complex, with most having complex life cycles involving different hosts or substrates, reproductive conditions, and spore activation conditions. Fungi are known to reproduce sexually via nuclear fusion and meiosis, parasexually, and asexually. Fungi are often capable of producing spores in high numbers, which act to spread the fungi to new areas for colonization, and as reservoirs of the population during unfavorable conditions. Some spores are even motile, containing flagella used to propel them. Many also produce sporocarps (commonly referred to as mushrooms) to spread spores. They are present in nearly every habitat across the globe, and play an important ecological role as saprotrophs, mutualistic symbionts, parasites, and hyperparasites. According to D. Moore, G.D Robson, and A.P.J Trinci (2020) using molecular phylogenetics their “has been estimated to be 11.7-13.2 million [species]. ...up to over 90% of the collected specimens may constitute undescribed species”(p.6). This indicates there are likely many exceptions to previously outlined properties, and mycologists still have millions of species to discover and describe.

The Ecological Importance of Fungi
Fungi play a key role in our global ecosystem. Being one of the first and only organisms to break down lignin, they play an important role in recycling nutrients in forests. “Clearly fungal decomposition of dead organic matter be it wood, or other plant litter, animal dung, or cadavers and bones, is an essential ecosystem function because it maintains soil nutrient availability…”(D. Moore, G.D Robson, A.P.J Trinci, 2020, p.341). D. Moore, G.D Robson, A.P.J Trinci (2020) also state that fungi aggregate soil particles, improving drainage, as well as serving as prey and predators for many soil organisms. Fungi that specialize in hunting nematodes have many adaptations for this predator function as seen in Figure 2. Mushrooms and truffles are also consumed by many organisms, and fungi can have major impacts on how much water is retained, and can be stored in soil. The number of ecosystem services fungi provide are immeasurable. Almost all species of plants are in some way dependent on them for growth. They regulate population sizes of many organisms, and can both be beneficial and harmful to mankind's agriculture. Fungal bioremediation is also capable of decomposing organic wastes produced by agriculture and industry thus they provide a vital service in protecting inland, and marine ecosystems.
The Intersection of Culture and Religion with Fungi
Psychoactive plants have long been a part of ancient religious and cultural practices. But the importance of mushrooms has largely been pushed outside of the public consciousness due to various stigmas and dogmas. According to Stamets (1996) “The sacramental use of mushrooms goes back at least seven thousand years, and probably extends to Paleolithic times” (p.11). The indigenous Mesoamerican people have long used psilocybin mushrooms in shamanic rites. Some mushroom cults even survive to this day in parts of South America. According to Stamets (1996) Mayan temple ruins contain mushroom motifs and mushroom stones which underscore the important cultural role mushrooms played. Aztec emperor Moctezuma was said to have held an annual feast called the Feast of Revelations in which participants would eat green mushrooms with honey, dance, and once the effects of the psychedelic mushrooms set in they would sit there nodding. Once worn off they would discuss amongst themselves what they had seen in their visions. In modern times psilocybin mushrooms can be found throughout the world. Typically in cow pastures, and in ornamental wood chip beds. The nature of fungi, and the production of spores enables them to travel long distances, and for long periods of time, and still produce viable hyphae once a suitable substrate is found. In modern times there is an increasing acceptance of the use of psychedelic mushrooms, with Colorado and Oregon legalizing, or decriminalizing possession. Proponents of the psilocybin mushrooms state that consuming them can provide profound spiritual, and introspective thought that is beneficial for the consumer. In addition to the Psilocybes, the Amanita mushrooms are a large important genus with some having hallucinogenic effects. A. muscaria contains ibotenic acid and muscimol. According to Webster and Weber (2007) “Certain ethnic groups (e.g in Siberia) have taken advantage of the hallucinogenic properties of A. muscaria to experience euphoria. Its use has extended to semi-religious practices in which shamans have induced themselves into trances in which they claim to have powers of revelation” (p.541). Albeit these practices have largely been discontinued in the modern day, with A. muscaria now largely being taken as a recreational drug.
The Economic and Medicinal Importance of Fungi
Fungi play an invaluable role in the production of food, medicine, and science. From brewers yeast and baking yeast, to antibiotics and anti fungicides, fungi provide much more than a condiment on top of a pizza. According to Stamets (2000) “In the past a parasitic fungus was viewed as biologically evil. This view is rapidly changing as science progresses. Montana State University Researchers have discovered a new parasitic fungus attacking the yew tree. This new species is called Taxomyces andreanae and it is medically significant for one notable feature: it produces minute quantities of the potent anti carcinogen Taxol, a proven treatment for breast cancer” (p.10). Mycologists are currently engaged in the work of bioprospecting to find new novel compounds for medicinal purposes. One of the most famous, and perhaps most accidental, yet important discoveries involving fungi was the discovery of penicillin. A powerful antibiotic that has saved the lives of countless individuals with bacterial infections. In terms of economic importance roughly 100 species of mushroom are cultivated for consumption. The description of which would require a textbook in its own right. Most of which involve cultivating spores on an agar plate, which are then transferred to a bag of grain, or other material before being transferred to a bulk substrate for the growth of the mushroom from mycelium. Many species are also incapable of being cultured with current techniques such as some species of truffles which require wild harvest, and fetch hundreds if not thousands of dollars per kilogram.
Fungi and the Future
Our society is dependent on fungi. Our ecosystem could not function without them, and our agriculture and industry would wither without their assistance. It has become increasingly apparent that more consideration must be taken to preserve fungi and provide habitats for them to thrive. Current logging and agricultural practices can have devastating impacts on fungal biodiversity. And when that biodiversity is lost, and unrealized benefits from yet discovered fungi disappear with them. That is not to say every species of fungi is benevolent or harmless. With global warming many fungi in the tropics will likely spread further from the equator potentially wreaking havoc on agriculture, and native fungal species, plants, and animals in temperate areas. Many species of fungi are also pathogenic, and can pose a serious risk to human health, and are increasingly becoming resistant to common fungicides. Which underscores the importance of the continued study of fungi into the future.

References
Moore, D., Robson, G. D., & Trinci, A. P. J. (2020). 21st Century Guidebook to Fungi (2nd ed.). Cambridge University Press. David Moore served as Reader in Genetics in the Faculty of Life Sciences. He was President of the British Mycological Society and served as Executive Editor of the journal of Fungal Biology. Geoffrey D. Robinson was a Senior Lecturer at the University of Manchester. Anthony P. J. Trinci is Emeritus Professor in the Faculty of Biology, Medicine and Health, at the University of Manchester. The text book is comprehensive and covers broad aspects of fungal classification, biology, ecology, and fungal interactions with humanity.
Stamets, P. (1996). Psilocybin mushrooms of the World: An Identification Guide. Ten Speed Press. Paul Stamets is a world renowned amateur mycologist who has studied the cultivation of mushrooms, the identification of psilocybin mushrooms, and societies interactions with fungi. This identification book covers the identification of psilocybin mushrooms, their uses, and what people have thought of them throughout history.
Stamets, P. (2000). Growing Gourmet and Medicinal Mushrooms shokuyō oyobi Yakuyō Kinoko no saibai (3rd ed.). Ten Speed Press. This guidebook was written by Paul Stamets, a world renowned amateur mycologist. It covers the cultivation of a wide variety of mushrooms and the methods required to do so. The book also touches on society's interaction with mushrooms, and some medicinal properties associated with them.
Webster, J., & Weber, R. (2007). Introduction to Fungi (3rd ed.). Cambridge University Press. John Webster is a professor of Biosciences at the University of Exeter. Roland Weber was a lecturer of Biotechnology at the University of Kaiserlautern. The textbook is a comprehensive exploration of Fungi and associated organisms. It covers biology, biochemistry, ecology, and the genetics of a wide range of classifications of fungi.

Julkaistu kesäkuu 1, 2023 08:05 AP. käyttäjältä bornstupid bornstupid | 1 havainto | 0 kommenttia | Jätä kommentti

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