Introduction to Botany 135: Magical Mushrooms and Mystical Molds
Grades
Let us first go over something that is of concern to everybody, how the course will be graded (The information below has also been reproduced at the end of your syllabus):
There will be two exams (25% each X 2 =
50%), mostly multiple choices, with a few short answers that are based mostly on
my lectures and readings from the course web page. The final exam will not be
cumulative, and will cover the lecture material starting from material following
the second exam. The
value of the final exam will be the same (25%) as one of the semester exams. A
term paper (25%) will be done on some topic of your choosing having to do with
some aspect of fungi. The topic does not necessarily have to be a topic that we
will be covering this semester. You can select any topic that you feel will be
of interest. However, before starting your paper please check with me ascertain
the appropriateness of the topic. Please try to decide on a topic and discuss
it with me as soon as possible. The paper should be between 8-12 pages and have
a detailed bibliography.
Extra Credit: The field trips listed above are optional. Each field trip
that you go on will be worth 2% of an exam (=2 points). Read a short story or
novel in which fungi play an integral part to the plot and write a critical
review. Credit will be dependent upon whether it is a short story or a novel.
Introduction
Before we begin, I want to tell you a little story about how I got into mycology. Consider this an icebreaker and a way of learning about the person who will be teaching this course and it may even amuse you.
I have fond memories of growing up in San Francisco, during the 1950's. One of the favorite things that my friends and I use to to do when I was a kid (from age 7-10) was going to downtown, Market Street, and walking around looking at the the many movie theaters there to see which one we wanted to go to. We would leave in the morning and find a feature that we wanted to see around 11:00. They were triple features in those days, and with the 25 cents that each of our parents gave us, we would stay to see each movie about two or three times. So it was usually dark by the time we left. We always had a great time and for 25 cents, our parents were rid of us for that entire day (even in those days, you couldn't get a baby sitter for that price). Our favorites were sci-fi and horror movies. Some of favorites were, and still are: The Day the Earth Stood Still and Forbidden Planet.
However, we also saw our share of what most people would have labeled as really terrible movies, but we liked them all. These included I Married a Monster From Outer Space and Queen of Outer Space.
Although none of these movies were based on real science, I think this was probably how I first became interested in science. However, it would be a few years later before I began taking any science courses, in school. My interest in science cooled considerably after taking my first science class, when I was in the 8th grade, where I felt that science was not all that fun and I did not seem to have an aptitude for it. It would not be until my junior year in high school that I would rekindle my interest in science, and it was at that time that I decided to go to college. My junior year was also when the original Star Trek first came out, which also fueled my interest in science. After graduating from high school, I started my undergraduate career, in Fall 1967, at San Francisco State College. As an undergraduate in college, I became interested in a number of sciences, astronomy, chemistry, physics, etc., but could not visualize having a career in those areas. I then tried some of the life sciences. I thought about marine biology, entomology, zoology. It would not be until during my sophomore year that I would decide on majoring in botany, but at that time I still did not entertain the idea of becoming a mycologist or in even taking mycology. So, what happened? Since I did become a mycologist, something obviously changed my mind.
A course that I planned to take during Fall 1969 was not offered. So, I went to see a graduate student that I knew and asked his advise on what course I could take during the fall. Without hesitation he recommended a course called "Biology of the Higher Fungi" and described the class with many superlatives such as "very interesting", "best class I ever took", etc. However, I was unconvinced. Other than what little I learned from my General Botany course, the only vision I had about fungi was of the growth that I saw on my food after it had somehow been contaminated. Nevertheless, I did enroll in the course because I needed the units and two of my friends were taking the course, one of them being female, whom I was very fond. Not the best reasons for taking a course. Once in the course, my interest in fungi came about through my mentor, Dr. Harry D. Thiers. It was from the enthusiasm that he was able to generate in his class that got many of his students interested in fungi.
I told you this story for two reasons. 1. Given a choice as to whether you would want to take a course on fungus or not, even with the recommendation from someone that you may respect, it seems likely that you would still have reservation about taking such a course. I think that this tendency probably has to do with the lack of knowledge about fungi and their place in the world. This leads to a fear of fungi and in this country, people as a whole, are mycophobic and tend to see fungi as disease causing organisms, wood rotters, organisms that are responsible for spoiling our food, etc. Another words, we generally do not look favorably upon fungi. In this course we will be studying these negative aspects of fungi, but we will also examine their positive impact and there are many of those. I will attempt to demonstrate this in a multidisciplinary fashion. Another words, we will look at how fungi have shaped history, science, politics, religions, cultures, etc.
My background is in mycology, the branch of botany that studies fungi. As with all scientists, today, I have a specific group of fungi in which I am interested and carry out research in this group of fungi. My area of expertise is in the taxonomy and systematic of basidiomycetes, e.g., mushrooms and puffballs, which does not tell you a lot since you are probably not familiar with most of what I just said and probably cannot describe a fungus or tell me what a fungus is. In the past, I have attempted to tell nonscientists what a fungus is and have often been unsuccessful. So, this time around I will do things slightly different. We will begin by trying to appreciate fungi and talk about the things that they can do. Many fungal activities impact our lives.
How Do Fungi Impact Our Lives?( A Summary of Most of the Topics Covered This Semester)
Fungi impact our lives everyday and have played a role in numerous, important, historical events. They have impact on the world around us as recyclers, pathogens and symbionts. I will summarize some examples and tell you about specific fungi and what they do, but will not say anything about the mechanism of how the fungi are able to carry out these activities. For example, you all know about some fungi being able to rot wood, but you do not know how they are able to do this. We will cover the "how" part, next week.
Fungi have played an important role throughout history, in every culture of the world. In the introduction of Mushroom, Molds and Miracles, Kavaler (1965) describes the role of fungi in the fall of the Roman Empire. The Roman Empire became a significant, world power by approximately 264 B.C. and would eventually rule the regions bordering the Mediterranean Sea, which included England, parts of Europe, the Middle East and Africa. Their vast empire would rule for 500 years before numerous invasions by barbarian tribes led to the eventual fall of Rome. If you are a student of history, you know that history is determined by a series of interconnected events and not by any single event. In the case of the Roman Empire, one of several events responsible for its decline came about following a period of abnormally heavy rainfall in the Mediterranean. The rain was initially a blessing that led to an increased yield in their wheat crop. However, with the excess in rainfall there also came the proliferation of various types of pathogenic fungi, such as "rusts", "smuts" "ergot", etc., which laid waste to the wheat fields. The Romans observed on their crops the orange, black or white powdery masses of spores, which were responsible for starting and further perpetuating the diseases, the rotted roots beneath the soil, the fallen plants due to the weakening of the stems and darkened leaves from various diseases. Even the very kernel of the grains were destroyed and replaced by a hard, black, boat-shaped structures called ergots. These diseases destroyed most of their crops. After many years of continued crop failures, hunger spread, leading to unrest among the Roman people. This unrest, caused by fungi, was one factor that led to the eventual fall of the Roman Empire. Other events contributed to the decline of Rome, but are not relevant to this course, but if you wish to read a summary of the decline of Rome, click here.
It is ironic that although fungi played such an important role in the decline of the Roman Empire, the actual causes of the crop failure were unknown to the Roman. It was not until the 19th. Century that fungi as well as other micoorganisms would even be recognized as the cause of diseases. As with many unexplained phenomenon, in many cultures, the Romans attributed their crop failures to the wrath of their gods. There are many other instances of fungi playing significant roles in recent historical events, such as the potato famine, in Ireland, during the mid 1850's and some that are very ancient that have been recorded in the Bible.
Fungi, however, should not only be looked upon as negative organisms because they contribute tremendously to our well being. In 1928, Alexander Fleming, a British bacteriologist, upon examining his bacterial cultures that he had recently started noticed that one of his cultures had become contaminated with a fungus. It was a common fungus that had started from spores that had blown into his culture and somehow succeeded in killing the bacteria. This inadvertent contamination led to one of the most significant discoveries of the 20th. Century. Those of you who have had a course in biology probably know that this led Fleming to his discovery of the "wonder drug" that we know as penicillin, and with it, a new era in the treatment of infectious bacterial diseases began. This discovery eventually led to the finding of numerous other antibiotics. Here then is an example of a fungus that has very beneficial, and relatively few people in the world have not benefited from the discovery of penicillin.
The type of fungi with which most people are familiar are the mushrooms. However, how many people actually know that mushrooms are fungi? Although our society, as a whole, is mycophobic, every state in this country has at least one society, club, group, etc. of members who are mushroom lovers who are dedicated to the collecting, identifying, eating (mycophagy) and even photographing wild mushrooms, i.e. non-cultivated mushrooms. Hawai‘i is probably one of the few places in this country that does not have such a mushroom hunters club. What kind of people belong to these clubs? I am a little embarrassed to say that my first impression about such people was, to put it politely, "a breed apart". Although those were probably not the precise words I thought of when I attended my first meeting of the San Francisco Mycological Society while I was still an undergraduate. However, as with meeting with any new group of people, once I got over what I thought was a very odd group of people, I found that they were from all walks of life and were just like "every day" people. You do not have to necessarily love mushrooms to eat them. It is not uncommon for restaurants to offer mushroom appetizers and entrees that contain usually cultivated mushrooms on their menus, and this is not restricted to western restaurants. You can find such items on the menu in Chinese, Japanese, Russian and many other ethnic restaurants where the eating of mushrooms is considered a delight. Species of local, favorite mushrooms can be found in most parts of the world. Even in Hawai‘i, where there is not a strong mushroom following, the pepieao-akua (often just pepieao), is a local favorite. Thus, many species of mushrooms are identified with specific cultures. There is also an economic side to this. Because of the demands for some mushrooms, mushroom cultivation is a multi-million dollar enterprise.
Although mushrooms may be appealing, they cannot play a major role in our diet since they are 99% water. However, fungi can still play a very significant role in the production of some of our important food products and beverages. When you're making bread, you put into the oven a pretty dense, heavy lump of dough, but after baking the dough, a fluffy loaf of bread comes out. The juice that is pressed from grapes is transformed into wine, sheep's' milk cheese is made into tart Roquefort cheese, a foul smelling rye mash becomes whisky, and malted grain is made into beer. The above products would not be possible without the activities of fungi.
The most controversial of fungal products are the psychoactive drugs. The most famous being LSD-25 and psilocybin. In today's society, these drugs are taken for recreational purposes. However, psilocybin, which is often ingested by consuming mushrooms from the genus Psilocybe, was/is also used by Native American Indian in some of their religious ceremonies and is regarded as being sacred. The more familiar of the two drugs is probably LSD-25. The intended purpose of this drug was for the treatment of certain forms of mental disorders. This was also true for psilocybin. However, because of their abuse as recreational drugs and the harm that has come about through this type of usage, possession of these drugs is no longer legal.
Although many species of fungi are responsible for producing some of our foods, some are also responsible for taking the food from our mouths. Any food that we can consume can also be consumed by various fungi. The annual quantities of food destroyed by fungi is very high. For example, when you're shipping fresh fruit by railroad cars, let us say that there are 25 carloads, the equivalent of 1 carloads will arrive rotten and must be disposed of. There are a number of fungi that derive their nutrition from stored food material. Undoubtedly, there are many of you who have this perception of all fungi. Also, you may believe that fungi can only contaminate food that is left out in warm, moist environments. However, fungi can survive and thrive in even the most harsh environments. Thus, even refrigerated food is not safe from fungal contamination nor is food safe in extremely dry environment. Dried grains are commonly stored in large silos where it is too dry to be contaminated by most fungi, but a handful of species can still grow in this type of environment.
Stored food is not the only commercial product that can be infected with fungi. Wood and wood products are commonly rotted by fungi, and numerous other commercial products can also be ruined by fungi. However, you may not attribute damage that occur in many commercial products to fungi. For example, how many of you have ever noticed that a few years after a house has been painted that paint may begin to blister, turn a different color and eventually peel off the surface? You automatically assume that this was all caused by rain, wind and sunlight or even neglect, which may be be the case, but another possible and even probable reason is that a fungus is eating away at your paint. Even material made from glass and rubber is not safe and can be damaged by fungi. Fungi may even etch the lens of your camera, telescope, eye-glasses, etc, and the rubber in your electrical insulation can become damaged.
From our first story you know that some fungi can cause various diseases on plants. Although fewer in number, fungi can also cause diseases in animals. At one time or another, some of you may have contracted fungal infections such as athlete's foot and ringworms. Although not pleasant, nobody dies from these types of infections. However, some fungal diseases such as Valley Fever and Histoplasmosis may be fatal. Regardless of the type of fungal diseases that you have contracted, they are usually difficult to treat.
So you can see that in the immediate world around us it would appear that the harm done by fungi would seem to be about in balanced with the good, but there is one thing that I only just mentioned, above, that makes fungi essential to all life on this planet. What function might they have that would make them so important? Each living organism, from the simplest one celled life-forms to multicellular, complex organisms such as ourselves, grow, reproduce and eventually die. We are then returned to the earth through the process of decomposition, by fungi and bacteria. In obtaining food from dead organisms, they literally reverse the life process. Another words, when an organism is growing it takes in food and uses that food to build complex compounds, i.e., proteins, carbohydrates, fats, etc. from the simpler chemicals, which results in the growth of an organism. The act of decomposition by fungi and bacterial reverses this process and breaks them down again, into various simple compounds composed of carbon, nitrogen, sulfur, phosphorous, etc., which are returned to the soil to maintain its fertility. These compounds can then be utilized by plants for their own growth processes. Animals then consume plants, which are then consume by other animals, until each in their turn become food for the fungi and bacteria again. Thus, without fungi, as well as bacteria, this "recycling of nutrients" in the soil would not be possible, and life on this planet could not exist. For this reason fungi and bacteria must have been one of the first organisms, although probably not the first, to exist on this planet. When the first Voyager mission was launched to Mars, in the 1970's, one of its objectives was to determine if life exists on Mars. Most of these tests involved taking soil samples. The reason for this is simple, if life did evolve on Mars, fungi (as well as bacteria) must also have evolved, because in order for life to continue, some sort of recycling organisms must exist. A camera was also launched with the probe on the off chance that there might be large animals walking around Mars, but none were seen. Thus, the existence of "little green men" on Mars, at least for now, is only something that exists in the imagination of science fiction writers.
Finally, let's look at the number of fungi relative to other organisms. There are, presently, approximately 1.5 million species of organisms that biologists have identified and thousands of species are added each year. It is estimated that the total biota on this planet is between 5-30 million species (Campbell, et al. 1996). Of this total, approximately 100,000 species are estimated to be fungi, a relatively small percentage of the total biota. However, many of these species are so wide-spread and the dominant organisms in many habitats that they must be considered one of the most successful organisms, in the world. Clyde Christensen, a former plant pathologist from the University of Minnesota stated in his book "The Molds and Man" that fungi may not inherit the Earth, but they do control a great deal of it. That's not quite true! They have, in fact, inherited the Earth on at least one occasion, and possibly more. An indication as to how successful fungi can become was found in the fossil records by Visscher et al (1996). It has long been known that about 250 million years ago, during what is known as the Permian Period, the largest mass extinction ever recorded occurred. The cause of this catastrophe is not known, but it has been estimated that approximately 90 percent of marine animals became extinct during this period. The emphasis was placed on extinction of marine animals because the oceans tend to be a more stable and uniform environment than the terrestrial. Thus, if most of the marine organisms became extinct during this period, extinction of the terrestrial life must have been even greater. Paleobiologists, biologists that study fossils, previously believed that only plants had gotten through this crisis with relatively few losses. However, examination by Visscher et al (1996) of plant fossils, from this period, indicated that plants suffered along with the rest of the world's biota. Plants from this period were found to have been fossilized with massive amounts of fungi. Normally, there is little evidence of fungi in the fossil records and seldom are they associated with plants, but because so many plants died off at this time, a great proliferation of fungi and bacteria occurred due to the sudden increase in dead organic material, much of which was fossilized. For this brief period in time, fungi and bacteria were the dominant life forms on Earth! A summary of this article, by Richard Monastersky, can be found in the March 1996 issue of Science News.
We will discuss the topics that I just summarized in more details throughout the semester. Many of these topics represent different disciplines within mycology. These include:
Plant Pathology: The discipline that studies plants and their diseases. Organisms involved in diseases of plants include bacteria, viruses and insects, as well.
Deterioration Mycology: The discipline that studies the harmful effects that fungi cause on commercial products.
Medical Mycology: The discipline that studies the diseases of animals, including man.
Aesthetic Mycology: The study of fungi for intellectual interest and curiosity.
Mycological Terms
mycophobic: Having a fear or aversion of fungi.
recyclers: Referring to the ability of some fungi (and bacteria) to extract and reuse dead organic material
pathogens: An agent that causes disease, especially a living microorganism such as a bacterium or fungus.
symbionts: A close organisms, between two organisms that is mutally benefitial to both organisms.
rusts: in plant pathology, name for a fungus of the order Uredinales and for the plant diseases such fungi cause. Rusts form reddish patches of spores on their hosts.
smuts: Plant diseases, especially of cereal grasses, caused by parasitic fungi of the order Ustilaginales that form black, powdery masses of spores on the affected parts.
ergot: Disease of rye and other cereals caused by a fungus (Claviceps purpurea), which appears among the grains of rye as dark purple structures. The ergots, which resemble rye seeds, contain certain active substances (alkaloids) that are poisonous.
spores: A small, usually one to several-celled reproductive body produced by certain bacteria, fungi, algae, and nonflowering plants that is capable of growing into a new organism.
penicillin: A group of broad-spectrum antibiotic drugs obtained from molds of the genus Penicillinum or produced synthetically, most active against gram-positive bacteria and used in the treatment of various infections and diseases.
mushroom: The various fleshy fungi characteristically having an umbrella-shaped cap borne on a stalk. Term usually refer to the edible species such as Agaricus bisporus, the common supermarket mushroom.
mycophagy: Consumption of fungi, usually referring to mushrooms.
Literature Cited and Further Readings
Kavaler, L. 1965. Mushrooms, Molds, and Miracles: The Strange Realm of Fungi. John Day Co., New York, NY. 318p.
Visscher, H., H. Brinkhuis, D.L. Dilcher, W.C. Elsik, Y. Eshet, C.V. Looy, M.R. Rampino, and A. Traverse. 1996. The terminal Paleozoic fungal event: Evidence of terrestrial ecosystem destabilization and collapse. Proc. Natl. Acad. Sci. USA, 93:2155-2158.
