Forensic mycology is the use of mycology in criminal investigations. [1] Mycology is used in estimating times of death or events by using known growth rates of fungi, in providing trace evidence, and in locating corpses. [1] It also includes tracking mold growth in buildings, the use of fungi in biological warfare, and the use of psychotropic and toxic fungus varieties as illicit drugs or causes of death. [1] [2]
The constant growth rate of fungi is used to determine post-mortem interval and help investigators pinpoint time of death. Traditionally, medical examiners will rely on body cooling, level of decomposition, and/or insect succession. [3] Fungi have been noted to be present on dead bodies but, until recently, were thought be little more than another organism aiding in decomposition. [3] There is no limit to which species of fungi or which parts of the body can be used in this process, as long as conditions at the scene can be experimentally recreated. [3]
H. van de Voorde and P. J. Van Dijck of the Catholic University of Leuven had the first noted use of recreating fungal growth to determine post-mortem interval in 1980. [4] In this, a woman, living alone, was found dead in a temperature-controlled house with stab wounds in her chest and fungal growth on her face and lower abdomen. [4] The body had already cooled to 12 °C, the ambient temperature, and showed no signs of insect colonization which made accurate post-mortem interval determination difficult. [4] van de Voorde and Van Dijck recorded the size of the fungal growth on the eye and obtained a sample. [4] This sample was incubated in similar conditions to the corpse and the time needed to grow the colony to the size on the body was used to determine port-mortem interval and, subsequently, the time of death, which was confirmed by the confession of the murderer. [3] [4] In addition to size, distinct phases of fungal growth can be used to aid in post-mortem determination. [4] Chronologically, these include the formation of substrate mycelium, aerial mycelium development, sporulation, and post-sporulation color changes. [4]
Multiple environmental factors, such as humidity and temperature, can affect the growth of these organisms, which should be taken into consideration when attempting to repeat conditions for comparative growth. [2]
The disposal of bodies, often in remote wooded areas, is often used to hide evidence critical to the investigational process. [3] [5] These shallow graves have high nutrient levels obtained from the decomposition of the body, making the surrounding soil high in nitrogen and other compounds attractive to fungal growth. [5] These environments are ideal for postputrefaction and ammonia fungi to colonize and thus these mushrooms are a common indicator of a clandestine burial. [5]
Ammonia fungi are common to environments with a high level of nitrogenous compounds. [5] Studies have found that ammonia, the byproduct of the decomposition of these compounds, is vital for the fruiting of these types of fungi. [5] When fungi are in close proximity to a burial, they are termed postputrefaction fungi. [5] While there is considerable overlap between these two classifications, there are some species that do not fall into both categories. For example, Rhopalomyces strangulatus is found on or around carcasses but does not rely on ammonia for fruiting, while Coprinus echinosporus needs nitrogenous compounds but is found in environments with no remains. [5] [6] Fungi in these categories have only been reported in woodland ecosystems, notably in both mammalian and avian remains as well as in some wasps nests. [5]
The geotropic nature of fungi also makes them an ideal indicator of gravesite disturbance. The stipe, commonly referred to as the 'stalk', always grows vertically while the pileus, or 'cap', grows horizontally. [3] After being disturbed, these mushrooms will reorientate and can subsequently be used by investigators to determine movement of a crime scene. [3]
Fungal spores and pollen are often used as mycological trace evidence. [2] The transfer of these microscopic particles occurs upon contact between objects or persons, in conjunction with Locard's Exchange Principle. This falls into the subdiscipline of forensic palynology.
Fungal spores are similar to pollen spores as they can be traced back to a certain location, giving them probative value as trace evidence. They also have the distinct ability to grow in places where plants cannot, such as stone, leather, plastic, brick, and tiles, increasing the chances of finding microscopic fungal spores. [7]
Humans have a documented history of ingesting fungi, namely mushrooms, whether they be edible, psychoactive, or poisonous. [3]
The onset and severity of symptoms after consumption of inedible species depends on the species, the person's tolerance, and the amount consumed. [3] Symptoms can range from mild discomfort, to major gastric disorders and sometimes death. [3] Symptoms may also initially seem similar to those produced by other medical conditions (e.g. cerebral infarction). [2] Due to most fungi being consumed and processed though the digestive system, it is common to have cases of poisoning where no intact specimens remain and/or where digestion has already begun. [2] [3] If this is the case, examination of fungal remnants such as partially digested organisms or microscopic spores may be preformed in the stomach and intestinal contents. [3] Further examination into the lower gut may be necessary in instances where the poisoning was slow acting and contents have already been digested. [2]
Certain species of fungi also contain psychoactive qualities when ingested, these are know colloquially as 'magic mushrooms". [2] These qualities come from substances derived from the fungi such as psilocybin, psilocin, and amanitin. [3] The concentrations of psychoactive chemicals in these fungi vary, even within species, due to ecological and biological factors. [3] As of the 1971 UN Convention, the possession and use of these substances and the fungi which they are derived from is strictly controlled, with psilocybin and psilocin being banned completely. [3]
The use of fungi in bioterrorism dates back to 600 B.C., when the Assyrians used the rye ergot fungus ( claviceps purpurea ) to contaminate enemy wells. [8] Currently, the fungi that have the greatest risk to the public are a specific set of molds that create a range of different mycotoxins, depending on the species. [9] These toxins are most often present on food products, such as nuts, dried fruit, and grains. They can also occur in soil, decaying vegetation, and animal feed. [9] Effects range from short-term severe illness to chronic conditions, with some resulting in death. [9]
The greatest limitation to using these as a biological weapon is the difficulty of dispersal and human to human transmission. [10] As of April 2022, The CDC currently does not currently list any fungal agents in their A or B categories for biological agents, which are reserved for pathogens presently at highest risk to society. [10]
The WHO classifies multiple species as Risk Level 3 Pathogens, which have a high risk to those affected but do not easily transmit between people. [11] [12]
These species include:
Mold growth commonly occurs in damp, humid environments and is often found in buildings. [2] These growths can affect those who are immunocompromised or have allergies to these organisms and should be investigated when a fungus-related death has occurred. [2] Evidence of these growths can also be used in civil lawsuits or water damage insurance claims. [2] Some common species found in buildings are Aspergillus glaucus, Aspergillus niger, Cladosporium cladosporioides, Cladosporium herbarum, and Stachybotrys chartarum, among others. [2]
A mushroom or toadstool is the fleshy, spore-bearing fruiting body of a fungus, typically produced above ground, on soil, or on its food source. Toadstool generally denotes one poisonous to humans.
Mycology is the branch of biology concerned with the study of fungi, including their genetic and biochemical properties, their taxonomy and their use to humans, including as a source for tinder, traditional medicine, food, and entheogens, as well as their dangers, such as toxicity or infection.
Ascomycota is a phylum of the kingdom Fungi that, together with the Basidiomycota, forms the subkingdom Dikarya. Its members are commonly known as the sac fungi or ascomycetes. It is the largest phylum of Fungi, with over 64,000 species. The defining feature of this fungal group is the "ascus", a microscopic sexual structure in which nonmotile spores, called ascospores, are formed. However, some species of the Ascomycota are asexual, meaning that they do not have a sexual cycle and thus do not form asci or ascospores. Familiar examples of sac fungi include morels, truffles, brewers' and bakers' yeast, dead man's fingers, and cup fungi. The fungal symbionts in the majority of lichens such as Cladonia belong to the Ascomycota.
A mold or mould is one of the structures that certain fungi can form. The dust-like, colored appearance of molds is due to the formation of spores containing fungal secondary metabolites. The spores are the dispersal units of the fungi. Not all fungi form molds. Some fungi form mushrooms; others grow as single cells and are called microfungi.
Psilocybe cubensis is a species of psilocybin mushroom of moderate potency whose principal active compounds are psilocybin and psilocin. Commonly called shrooms, magic mushrooms, golden halos, cubes, or gold caps, it belongs to the fungus family Hymenogastraceae and was previously known as Stropharia cubensis. It is the best-known psilocybin mushroom due to its wide distribution and ease of cultivation. This mushroom being optimal for home cultivation specifically, as was suggested in the 1970s, is primarily what led to cubensis being the psilocybin mushroom species most common on the black market as a street drug.
Decomposition or rot is the process by which dead organic substances are broken down into simpler organic or inorganic matter such as carbon dioxide, water, simple sugars and mineral salts. The process is a part of the nutrient cycle and is essential for recycling the finite matter that occupies physical space in the biosphere. Bodies of living organisms begin to decompose shortly after death. Animals, such as worms, also help decompose the organic materials. Organisms that do this are known as decomposers or detritivores. Although no two organisms decompose in the same way, they all undergo the same sequential stages of decomposition. The science which studies decomposition is generally referred to as taphonomy from the Greek word taphos, meaning tomb. Decomposition can also be a gradual process for organisms that have extended periods of dormancy.
Polypores are a group of fungi that form large fruiting bodies with pores or tubes on the underside. They are a morphological group of basidiomycetes-like gilled mushrooms and hydnoid fungi, and not all polypores are closely related to each other. Polypores are also called bracket fungi or shelf fungi, and they characteristically produce woody, shelf- or bracket-shaped or occasionally circular fruiting bodies that are called conks.
Psilocybe semilanceata, commonly known as the liberty cap, is a species of fungus which produces the psychoactive compounds psilocybin, psilocin and baeocystin. It is both one of the most widely distributed psilocybin mushrooms in nature, and one of the most potent. The mushrooms have a distinctive conical to bell-shaped cap, up to 2.5 cm (1 in) in diameter, with a small nipple-like protrusion on the top. They are yellow to brown, covered with radial grooves when moist, and fade to a lighter color as they mature. Their stipes tend to be slender and long, and the same color or slightly lighter than the cap. The gill attachment to the stipe is adnexed, and they are initially cream-colored before tinting purple to black as the spores mature. The spores are dark purplish-brown in mass, ellipsoid in shape, and measure 10.5–15 by 6.5–8.5 micrometres.
Psilocybe cyanescens is a species of potent psychedelic mushroom. The main compounds responsible for its psychedelic effects are psilocybin and psilocin. It belongs to the family Hymenogastraceae. A formal description of the species was published by Elsie Wakefield in 1946 in the Transactions of the British Mycological Society, based on a specimen she had recently collected at Kew Gardens. She had begun collecting the species as early as 1910. The mushroom is not generally regarded as being physically dangerous to adults. Since all the psychoactive compounds in P. cyanescens are water-soluble, the fruiting bodies can be rendered non-psychoactive through parboiling, allowing their culinary use. However, since most people find them overly bitter and they are too small to have great nutritive value, this is not frequently done.
Hericium erinaceus is an edible mushroom belonging to the tooth fungus group. Native to North America, Europe, and Asia, it can be identified by its long spines, occurrence on hardwoods, and tendency to grow a single clump of dangling spines. The fruit bodies can be harvested for culinary use.
Forensic entomological decomposition is how insects decompose and what that means for timing and information in criminal investigations. Medicolegal entomology is a branch of forensic entomology that applies the study of insects to criminal investigations, and is commonly used in death investigations for estimating the post-mortem interval (PMI). One method of obtaining this estimate uses the time and pattern of arthropod colonization. This method will provide an estimation of the period of insect activity, which may or may not correlate exactly with the time of death. While insect successional data may not provide as accurate an estimate during the early stages of decomposition as developmental data, it is applicable for later decompositional stages and can be accurate for periods up to a few years.
A fungus is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from the other eukaryotic kingdoms, which, by one traditional classification, includes Plantae, Animalia, Protozoa, and Chromista.
Rhodotus is a genus in the fungus family Physalacriaceae. There are two species in the genus with the best known, Rhodotus palmatus, called the netted rhodotus, the rosy veincap, or the wrinkled peach. This uncommon species has a circumboreal distribution, and has been collected in eastern North America, northern Africa, Europe, and Asia; declining populations in Europe have led to its appearance in over half of the European fungal Red Lists of threatened species. Typically found growing on the stumps and logs of rotting hardwoods, mature specimens may usually be identified by the pinkish color and the distinctive ridged and veined surface of their rubbery caps; variations in the color and quantity of light received during development lead to variations in the size, shape, and cap color of fruit bodies.
Panellus stipticus, commonly known as the bitter oyster, the astringent panus, the luminescent panellus, or the stiptic fungus, is a species of fungus in the family Mycenaceae, and the type species of the genus Panellus. A common and widely distributed species, it is found in Asia, Australia, Europe, and North America, where it grows in groups or dense overlapping clusters on the logs, stumps, and trunks of deciduous trees, especially beech, oak, and birch. During the development of the fruit bodies, the mushrooms start out as tiny white knobs, which, over a period of one to three months, develop into fan- or kidney-shaped caps that measure up to 3 cm (1.2 in) broad. The caps are orange-yellow to brownish, and attached to the decaying wood by short stubby stalks that are connected off-center or on the side of the caps. The fungus was given its current scientific name in 1879, but has been known by many names since French mycologist Jean Bulliard first described it as Agaricus stypticus in 1783. Molecular phylogenetic analysis revealed P. stipticus to have a close genetic relationship with members of the genus Mycena.
Microbiology of decomposition is the study of all microorganisms involved in decomposition, the chemical and physical processes during which organic matter is broken down and reduced to its original elements.
The Nidulariaceae are a family of fungi in the order Agaricales. Commonly known as the bird's nest fungi, their fruiting bodies resemble tiny egg-filled birds' nests. As they are saprobic, feeding on decomposing organic matter, they are often seen growing on decaying wood and in soils enriched with wood chips or bark mulch; they have a widespread distribution in most ecological regions. The five genera within the family, namely, Crucibulum, Cyathus, Mycocalia, Nidula, and Nidularia, are distinguished from each other by differences in morphology and peridiole structure; more recently, phylogenetic analysis and comparison of DNA sequences is guiding new decisions in the taxonomic organization of this family.
Fungi – "Fungi" is plural for "fungus". A fungus is any member of the group of eukaryotic organisms that includes unicellular microorganisms such as yeasts and molds, as well as multicellular fungi that produce familiar fruiting forms known as mushrooms. Biologists classify these organisms as a kingdom, Fungi, the second highest taxonomic rank of living organism beneath the Eukaryota domain; other kingdoms include plants, animals, protists, and bacteria. One difference that places fungi in a different kingdom is that their cell walls contain chitin, unlike the cell walls of plants, bacteria and some protists. Similar to animals, fungi are heterotrophs, that is, they acquire their food by absorbing dissolved molecules, typically by secreting digestive enzymes into their environment. Growth is their means of mobility, except for spores, which may travel through air or water. Fungi function as the principal decomposers in ecological systems.
Stropharia caerulea, commonly known as the blue roundhead, is an inedible species of agaric fungus in the family Strophariaceae. It is a common species found in Europe and North America, where it grows as a saprophyte in meadows, roadsides, hedgerows, gardens, and woodchip mulch. S. caerulea was officially described to science in 1979, although it was known to be a distinct species for about two centuries before that. The taxon Stropharia cyanea, as defined by Risto Tuomikoski in 1953, and used by several later authors, is a synonym of S. caerulea.
Human interactions with fungi include both beneficial uses, whether practical or symbolic, and harmful interactions such as when fungi damage crops, timber, food, or are pathogenic to animals.
Fungi are a common theme or working material in art. They appear in many different artworks around the world, starting as early as around 8000 BCE. Fungi appear in nearly all artforms, including literature, paintings, and graphic arts; and more recently, contemporary art, music, photography, comic books, sculptures, video games, dance, cuisine, architecture, fashion, and design. There are a few exhibitions dedicated to fungi, and even an entire museum.