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This chapter discusses the fungal diseases (or mycoses) of humans. Topics covered include benign infections of the skin, hair, and nails caused by fungi called dermatophytes; Madurella mycetomatis, the fungus that causes mycetoma of the foot; a yeast called Cryptococcus neoformans that causes meningitis in about 10% of AIDS patients; melanized fungi; and one group of zygomycete fungi, the Mucorales, which cause a family of infections, termed the mucormycoses.

This chapter describes the global pandemic of Dutch elm disease caused by the fungus, Ophiostoma ulmi. Dutch elm disease was the worst epidemic of urban trees in history. Besides the fascinating biology of the interaction between elm trees and this fungus, the chapter also tells compelling stories about the women scientists, led by Johanna Westerdijk, who first identified the cause of the epidemic.

This chapter describes the history and continuing impact of the rust fungus, Hemileia vastatrix, on coffee crops. In the 19th century, this pathogen wiped-out coffee crops in Ceylon (Sri Lanka) and transformed the country into a tea-producing island. The scientist Harry Marshall Ward played a key role in the story of coffee rust, and was posted to Ceylon in 1880 to identify the cause of the epidemic. Coffee rust remains an exceedingly important agricultural problem in the developing world. A diversity of stories about the biology and sociology of this fungal disease of international importance is presented.

This chapter examines the interactions between trees and fungus-growing-leaf-cutter ants, arguing that we can learn much from natural communities as long as we don't mistakenly assume perfection. It shows that natural selection can improve the fitness of each participant in multispecies interactions, regardless of the impact on the community as a whole. The chapter begins with an evolutionary perspective on chemicals as either signals, cues, or manipulation. This is followed by a discussion of the fungus-growing ants, with particular emphasis on their natural strategies for pest control, and the use of biotechnology for biological control of pests. The chapter concludes by stressing the importance of natural ecosystems in providing essential context for understanding the sophisticated adaptations of wild species, before applying them to agriculture.

Compared to the overwhelming evidence of active seasonal adaptation in plants and animals, little is known about seasonality and photoperiodism in fungi. To approach this topic in any organism, several questions have to be answered: (1) Is there evidence for seasonality?; (2) Is there evidence for photobiology — a prerequisite for detecting changing lengths of day and night?; and, (3) Is there evidence for a circadian system that could be used as internal reference to make sense of the changes in day or night length? This chapter summarizes what is known about the questions enumerated above. It describes the first results of investigating seasonality and photoperiodism in Neurospora crassa, a classic model organism in circadian research. As in other organisms, the Neurospora photoperiodic responses rely on a functional circadian clock that involves determination of night length.

This chapter considers other fungi that grow in buildings. Meruliporia incrassata has become a frequent problem in California, where its massive rootlike organs, called rhizomorphs, snake into homes and destroy their timber frames. Serpula lacrymans causes dry rot in Europe and has plagued buildings and wooden ships for hundreds of years. Samuel Pepys was exasperated by the effects of dry rot on the Royal Navy in the 17th century, and Thomas Faraday sought a “cure” for this fungus in the 19th century. Dry rot appeared in the writings of Charles Dickens and Edgar Allen Poe, and is also mentioned in Leviticus. A microbial menace, called the artillery fungus, that uses a miniature cannon to shoot its black spore-filled balls onto new food sources is described. This extraordinary feat of biomechanics causes this fungus to spatter itself onto automobiles, serving as yet another fungal stimulus for lawsuits.

This chapter discusses phallic mushrooms. Phallic mushrooms belong to a large group of fungi that includes the more familiar organisms that generate brackets on trees and buttons and portabella caps. These organisms are members of a group of fungi called the Basidiomycota, a name that refers to a special kind of spore or microscopic seed called the basidiospore. Thirty thousand species of basidiomycete have been described by scientists, and seventy or so are phallic mushrooms and related fungi that manufacture smelly cages.

This chapter discusses the invasive growth of the fungus and its voracious appetite. Fungi grow by extending the tips of their hyphae and by branching to initiate new hyphae. As the organism expands, it forms a maze of filaments whose pattern bears some resemblance to a series of river deltas. This is the colony or mycelium, the feeding phase of the fungus. Most often, hyphal growth is invasive, so mycelia develop inside the food source (or substrate) utilized by the fungus.

This chapter discusses fungus that infects insects. The Cordyceps fungus, for instance, is capable of piercing the chitinous exoskeleton of insects. Although Cordyceps poses no threat to humans, its relative Claviceps is a source of great misery to us. Claviceps is the ergot fungus, a pathogen of rye whose toxins cause blood vessels to constrict so powerfully that hands and feet become gangrenous, causing patients to shed their nails and, eventually, their hands or feet. Saccharomyces cerevisiae, Ascobolus immerses, and lichens are also described.

This chapter discusses the biology of a cross-section of aquatic fungi. In fast-flowing creeks, foams froth around half-submerged branches or at the bottom of waterfalls. Cakes of foam trap and concentrate the same kinds of marvelous spores all over the world: some are star-shaped with thin limbs connected to a central hub, others are crescent-shaped or sigmoid (an elongated S twisted into an extended helix), and a few combine these features and look like animals created by balloon sculptors. These are the conidia of Ingoldian hyphomycetes, named for their discoverer, Cecil Terence Ingold. As a young professor in Leicester in 1938, Ingold found them in foam that collected in “a little, alder-lined, babbling brook” close to his home. After months of research, he concluded that the spores were formed by a hitherto unknown group of aquatic fungi that were instrumental in leaf decomposition.

This chapter explores the mechanisms that enable fungi to communicate with one another during reproduction, and related signaling processes that allow hyphae to cooperate when they form fruiting bodies. Topics discussed include reproduction by oomycete water molds, water molds that are self-fertile hermaphrodites, zygomycete sex, and sexual behavior in mushroom-forming fungi.

This chapter discusses poisonous mushrooms. These include the Amanita virosa, which produces amatoxins, miniproteins or peptides that are absorbed from the intestine and lay waste to the liver; the death cap, Amanita phalloides, which is responsible for most fatal poisonings throughout Europe; and the autumn skullcap, Galerina autumnalis, a common woodrotting fungus that buries its mycelium in fallen logs.

This chapter discusses the plant diseases caused by fungi. Fungi cause more plant diseases than all other enemies combined. Since the beginning of agriculture, livelihoods and lives have been lost to rusts, smuts, bunts, mildews, potato blight, and rice blast. Of particular significance in this discussion is a pestilence called coffee rust that ravages an indispensable coffee crop in South America. Fungi also spoil food after it has been harvested, rotting fruits and vegetables during storage, transport, and in the recesses of refrigerators.

Forests are more than just groups of trees, they are home to many organisms. In a forest one can see the scrape marks of deer and bear, the thick growth of mistletoes and shelf fungi, and the damage of bark beetles and sapsuckers. The trees themselves are the focus of our interest, whether they are deciduous or evergreen, how large they are, and when they leaf out and senesce. This chapter begins with different kinds of forests and then considers signs left by other residents of the forest.

One of the greatest challenges facing applied ecologists is to elucidate causes of unwanted developments in natural and production ecosystems, and to translate this knowledge into management decisions without causing unintended side-effects. Such a strategy requires interventions based on solid understanding of the underlying mechanisms, as well as proper predictions of future direct and indirect effects of the interventions. Good applied ecological research quite often may reveal our shortage of knowledge, which in turn will fuel fundamental research initiatives. Community ecology plays a key role in many aspects of applied ecology because the abundance of species strongly depends on competitive and predatory interactions among species that are part of food webs. Food web interactions are major drivers of ecosystem processes, and they are key to the delivery of ecosystem goods and services.

There are more than 16,000 species of mushrooms. These include species with familiar umbrella-shaped fruit bodies, brackets with gills, spines, and tubes, and others that bear spores on flattened crusts, plus puffballs, earth stars, bird's nest fungi, phallic mushrooms, false truffles, and jelly fungi. Classical taxonomic studies relied upon mushroom shape, spore color, and other visible features of these fungi. This work has been overhauled in light of molecular phylogenetic research, demonstrating that similarities in appearance are a poor reflection of evolutionary relationships. Mushroom colonies determine soil fertility; they rot wood and decompose leaf litter; they clothe and feed the roots of forest trees; they are destructive parasites of plants; they form symbioses with orchids, ants, termites, and other animals, and a few form lichens. In rare cases, mushroom spores take root in an unfortunate person's nose or throat and rot them like a fallen tree.