Fungus
Evolution
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Diverged 1.5 billion years ago
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Gymnosperms - 300 mya
First land plants – 500 mya
400 mya current phyla emerged
After the Permian-Triassic extinction 251.4
mya, fungus ruled the world....
Fossil record is scant because fungus are
so mysterious.... And they don’t
biomineralize.
Est. 1.5 to 5 million species – only 5% have
been formally classified!
Zygomycota
Ascomycota
Basidiomycota
Ecological
Importance
Decomposition
Symbiosis with plants
(mycorrhizae)
Economic Importance
Fermentation
Food
Economic Importance:
Antibiotics
Characteristcs of
fungi
• Feed by absorption
• Most are multicellular
• Thread-like filaments called hyphae
• Hyphae organized into mycelium
• Asexual and sexual reproduction
• Chitin cell walls
Heterokaryotic
stage
Fusion of cytoplasm
Fusion of nuclei
Diploid stage
Haploid stage
Ballistospores
30,000 species (at least) have the capability to shoot spores
Pilobolus can fire spores at 20,000 Gs. This is only slightly
faster than a bullet. Nothing else in biology comes close.
Zygomycota
Zygote fungi
Rhizopus stolonifer
Pilobolus crystallinus
Ascomycota: Sac fungi
Peziza
Morels
Ergot
Penicillium
Morelss
Ergot alkaloids
Responsible for
Salem witch trials?
Ergotamine is a
precursor to LSD
Basidiomycota: Club
fungi
Pileus
Stipe
Gills
basidium
Fungi imperfecti (once called Deuteromycota)
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Imperfect or asexual fungi
Reproduce only vegetatively (asexually)
Many human diseases are imperfect fungi
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Athlete’s foot, ringworm, candida “yeast” infections
A fungi from this group (penicillium) is used to make
Roquefort and blue cheeses
Lichen
a symbiotic relationship between fungi and
algae or cyanobacteria (commonly Nostoc)
Fungi Similarities
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All are composed of eukaryotic cells (nucleus + organelles)
All are heterotrophic (derive energy from other organisms)
Absorptive nutrition (they don’t chew. they absorb.)
All have cell walls made of chitin.