Morel mushrooms evolve from a single-celled yeast during each ice age cycle. Ice ages have been cycling at exactly 100 thousand year intervals for several cycles. It could be a water clock in the Pacific Ocean that sets the exact timing, or it could be a hot spot in the Earth's center, perhaps the earth's core, that rotates at that frequency. The cycles are not a result of the Earth's tilt and rotation (called the Milankovich Cycles) as physicists claim, because they are too complex and muddled to produce a uniform result, and they go back more than a few ice age cycles.

The yeast that the morel evolved from is probably the filamentous yeast, Schizosaccharomyces japonicus, because both have eight spores in a row in the ascus. Such micromorphology cannot change in the short amount of time that the morel has been evolving. There could be an undiscovered yeast with eight spores in a row, because yeasts are difficult to find in the wild.

The yeast grew at the base of a tree for about 50 thousand years extending into the soil and feeding upon Pseudomonas fluorescens and similar bacteria which thrive in cold, spring soil. This process could only occur at the face of the ice cliff, which causes the morel to re-evolve during each ice age cycle.When the ice cliff of an ice age gets developed, it creates very extreme and unusual conditions. The coldness draws moisture out of the air, just as a dehumidifier does. So in front of the ice cliff is hot, dry air. As cold air drops down the face of the ice cliff, it forms cold, wet fog which flows over the surface of the ground, with hot dry air above it. This combination is required for the morel to evolve.

Yeasts do not tolerate drying, because they evolved in sugary solutions, and very demanding physiology is required for tolerating drying. As yeasts evolved from molds during the biological transition 65 million years ago, they gave up the demanding physiology which molds acquired for tolerating drying. So morels do not tolerate drying, as they still have the physiology which they acquired from their yeast ancestor.

Therefore, the yeast could only evolve at the base of trees where the air was continuously cold, wet fog. Yet the trees required sunlight for photosynthesis. So the cold, wet fog sweeping off the ice cliff was the only possible way to create suitable conditions near the ground for yeast growth and photosynthesis where the leaves are.

The yeast filaments extending from the tree trunk into the soil continued to do what yeasts do in excreting acid to kill bacteria and feed on them. Yeast cells can tolerate more acid than bacteria can being eukaryotic, while bacteria have a more primitive physiology being prokaryotic. I have found that P. fluorescens autolyzes around pH 5.0, while yeasts tolerate much more acidic conditions.

Evidence that the yeast grew on a surface at the base of trees is found under laboratory conditions where the morel reverts to differentiated surface growth on agar media creating a dramatic anomaly. I show numerous photos of the anomaly. Reverting to that type of growth under laboratory conditions indicates that the morel ancestor spent more time growing at the base of tress than as a free growing mushroom.

So an ice age cycle can be divided into three sections for morel evolution. About 30 thousand years can be attributed to formation of a large ice sheet, about 50 thousand years can be attributed to a yeast growing at the base of trees, and about 20 thousand years can be attributed to the morel evolving as a free growing mushroom in the soil.

The morel cannot survive more than one ice age cycle because of its extremely poor characteristics in forming ascospores. Evidence of the morel evolving in two previous ice age cycles is in two cup fungi, Disciotis venosa and Discina leucoxantha. The cup shape increases survivability for ascomycetes but not well enough for long term survival. These two cup fungi were said to have identifying features on the spore surface similar to the spore surface of morels (Nancy Smith Weber, A Morel Hunter’s Companion, 1988).

The cup shape improves survivability for fleshy ascomycetes, but the cup shape is still a losing battle for ascospores. There are some cup-shaped molds that have been around for a long time, but they have highly stable niches that do not create extreme demands for tolerating variations in environmental conditions.

The main problem with ascospores is they are trapped inside cells and do not disseminate easily. The morel requires two or three days for spores to form after morels emerge from the ground. The morels must stay well humidified while spores are forming to complete the process and produce viable spores. Then the tissue must dry to create shrinkage which forces the spores to be propelled out. That set of conditions is not easily met. So morels do not get spores out in a reliable way. Even after spores are propelled out, they do not easily get picked up by wind.

Morels disseminate so poorly that their characteristics are noticeably different about every 100 miles of ground space. If spores were more widely dispersed, the gene pool would be homogenized over a wide area. But variations in morel appearance are only extreme where conditions are extreme such as the central plains of the U.S. Coastal morels grow under milder and more uniform conditions, so variations are not so extreme.

The cup shape is a partial but ineffective improvement in getting ascospores out of the tissue. The cup shape allows slow drying close to the ground and fast drying around the rim. So someplace between the extremes the tissue dries at the right rate most of the time for getting spores out. But the process is still so problematic that no more than two ice age cycles have produced cup-shaped variants of the morel.

It is not exactly the morel that evolves into a cup fungus. It is a close relative called Helvela crispa. This variant is what the morel line evolved into for dryer conditions later in the spring. H. crispa is half way between the morel and a cup fungus. It's cap looks like a potato chip hanging over the stalk. It has faster and slower drying areas without the cup shape. So it would be the variant that evolves into the cup shape as the ice age cycle progresses.

The physiology of morels is also not conducive to long-term survival. Physiology does not evolve easily, as it is dependent upon the micro-structure of the cells, which cannot change easily. A large part of cell metabolism is controlled by proteins attached to membranes for moving metabolites precisely from one reaction site to another. Any rearrangement is quite disruptive, which means evolution is countered by the need for precise order within the cells.

Macromorphology doesn't have that problem, because all it has to do is count so many cells in each direction. So macromorphology evolves quite easily and rapidly, while micromorphology and physiology evolve much more slowly.

So a yeast could change morphologically into a mushroom while the physiology and micromorphology remains the same as that of the yeast.

A detrimental result is that the morel still maintains autolysis, as approximately all bacteria and yeasts do, while the process is quite disadvantageous for the morel. Autolysis means the cells break open with age and recycle nutrients. With bacteria and yeasts, autolysis occurs in about two or three days under laboratory conditions. But such conditions are quite unnatural, so the life cycle could be longer under natural conditions.

Autolysis is valuable for bacteria and yeasts in making ideal nutrients available. As the cells break down, they reduce macromolecules to subunits. Proteins are reduced to amino acids and genetic material is reduced to nucleosides, which includes a removal of the phosphate. Three enzymes are used to reduce genetic material to nucleosides.

The phosphate of nucleic acids is too problematic for metabolism to be left attached for nutritional purposes. The phosphate attachment is very strong and high in energy, which makes the backbone of the DNA structure strong. This is why energy is carried with three phosphates attached to each other in ATP (adenosine triphosphate). Each addition of phosphate to phosphate has less energy in its bonds; so the third phosphate has the right amount of energy for general metabolism.

Humans do not use genetic material as a nutrient, because a three enzyme system would be too demanding for such a small mass of nutrients, and the monomers would be located in the wrong place. Going through the blood would require a carrier, and going through the cytoplasm of cells to get to the nucleus would be disruptive. So E. coli evolved symbiotically in the large intestine to break down the genetic material; and E. coli would be the second oldest bacterium next to P. fluorescens, though Streptomycetes would have evolved in the soil at about the same time originating with molds rather than the Gram-negative bacterial line that P. fluorescens created.

About 541 million yeasts ago, a planet exploded between Mars and Jupiter causing a layer of clay about a foot deep to cover the Earth. Before then, shale and its ocean sediments created the closest thing to soil, which was inhospitable to terrestrial life. Also, highly critical minerals were added to the Earth's surface, which appears to be the primary factor resulting in the "Cambrian Explosion" of biological diversity that occurred at that time. Animal life was just beginning, so E. coli would have been evolving in the animal digestive system. The clay also allowed filamentous fungi to evolve into Streptomycetes (prokaryotic cells in the soil referred to as bacteria) at that time.

E. coli breaking down genetic material in the large intestine produces carbon dioxide gas. Biologists don't know that, so they are trying to create a type of beans which are not gassy using trial-and-error. They don't know that they would have to remove the genetic material from the food to succeed.

Residual autolysis is detrimental to the morel, but evolving away that type of physiology would take more time than the morel has had. Autolysis occurs about 4-5 days after morels emerge. It starts with one side of the mushroom deliquescing, and Gram-negative bacteria grow on the deteriorating cell material. If people eat old morels, the Gram-negative bacteria make them sick, as there is endotoxin in the cell walls of Gram-negative bacteria.

There is an innate form of deliquescence used by Shaggy Manes (Coprinus comatus) for getting spores to the ground in the same location every year. Shortly after gills form and put a few spores into the air, C. comatus liquefies causing the remaining spores to drop to the ground. The reason why this happens is because C. comatus prefers a highly particular set of conditions, which apparently means rich nutrients; and when it finds the right spot, it wants to keep growing there. But the mycelium will not survive through winter freezing, so it puts spores on the ground each year for surviving winter freezing.

The main form of nutrition for Gram-negative bacteria while they were evolving was to attack other cells and feed on them. Using cell material as nutrients created a high-nitrogen nutrition. Gram-positive bacteria evolved with modern biology beginning 65 million years ago, as Streptomycetes competed with molds in the new sugary solutions that modern plants produced. So Gram-positives prefer carbohydrate nutrients, where Gram-negatives prefer high-nitrogen nutrients.

Therefore, some plants and mushrooms promote the growth of Gram-positive bacteria on their surface to protect against Gram-negative bacteria. To do this, they would excrete carbohydrates which favor Gram-positive bacteria. Examples include mushrooms that produce a viscous cap when wet such as Agaricus and plants such as green beans. If green beans are allowed to age under humid conditions, they acquire a coating which is sort of buttery. It's ok to eat, because it would be Gram-positive bacteria promoted for protecting against Gram-negative bacteria. I haven't identified the bacteria, but they would probably be Bacillus cereus or Bacillus subtilis. One of those probably evolved on mushroom caps, and the other on green plants.

The difficulty in getting ascospores out resulted in yeasts, and therefore morels, producing a large amount of phenotypic variation as a substitute for genotypic variation. Higher organism use sexuality to produce rapid genotypic variation, and where rapidly changing environmental conditions are important, phenotypic variation is used. It is usually seasonal variation that requires phenotypic variation, such as Elm trees forming some blossoms early in the spring and some a month or more later, so an early frost doesn't damage the later ones. Humans use two types of muscle cells, fast and slow, for phenotypic variation. Each person has a different combination of fast and slow muscle cells. This variation is randomized through the population rather than following Mendelian lines of descent from parents to offspring. Randomization is the test of phenotypic variation.

Yeasts are difficult to identify through biochemical tests, because phenotypic variation is so high that consistent results are not found. Yeasts will produce different ratios of acetic acid and ethyl alcohol based on phenotypic variation, which is one of the reasons why wine quality varies from year to year. Controlling the phenotypes should allow greater control over wine quality, but enologists don't seem to understand that sort of complexity. So they try to control quality through chemistry instead of genetics.

Morels produce so much phenotypic variation that there would not statistically be any two morels the same, except that the spores are produced in identical pairs, which means there are always two potential outgrowths that are the same.

About ninety percent of the phenotypes of morels do not produce functional spores. In fact, some morels are quite weird looking due to the randomness of characteristics in the phenotypes. It's certainly inefficient to produce nonfunctional morels, but morels haven't had enough evolutionary time to refine the process. So they scramble the possibilities in a random manner each time a pair of spores are formed. There would be several dozen options scrambled each time.

When enzymes of the morel TCA cycle are separated, about 3-5 allotypes are found for each enzyme. Morel scientists do not know why, so they try to use the differences for taxonomic purposes, but fail, because phenotypes do not show genetic differences. Scientists have noticed allotype differences and multiple alleles on chromosomes for a long time but could never understand why they exist. The multiple allotypes and alleles create phenotypic differences. Only the horticulturists have a concept of phenotypic differences altering their products, so they use cuttings instead of seeds when they want to get uniform phenotypes. Communication between scientists is so limited that the significance of phenotypic differences does not spread from horticulturists to other scientists.

The need for control over phenotypic variations is shown by the oldest mushroom, the puffball (the oldest, mainline version of the puffball) which took form 300 million years ago. It forms four phenotypes, and they come up in succession from the same mycelium. Once every ten years. The mycelium grows underground continuously, surviving through freezing winters and thriving on the hardest ground. The mycelium likes to grow on hard car trails, because the reduced vegetation allows spores to get airborne easier.
 

 
Both the puffball and Agarics send spores high into the atmosphere for dissemination, and the spores do not germinate otherwise. The vacuum environment would be the test used. The result is widely scattered appearances, so disease and insects do not develop against them. The mycelium of puffballs staying under the ground also prevents disease and insects from developing.

The fact that Agarics and puffballs (of the original types) do not appear in groups with more than one mycelial mass, means the spores do not germinate unless they have traveled high in the atmosphere.

Extreme Evolution

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