Leavened bread
S. cerevisiae releases CO2 that lifts gluten. Wild sourdough adds lactic bacteria beside the yeast.
A kitchen already runs fungal factories: risen dough, soy sauce koji, blue cheese. The same kingdom includes athlete's foot and the oak-killing sudden oak death-adjacent stories in forests.
Chasing zero mould in a living house fights physics. Control moisture; target high-risk rooms; leave forest soils unsterilised on purpose.
Everyday uses
Koji and soy
Aspergillus oryzae builds koji for soy sauce, miso and some rice wines — East Asian domestication of a mould.
Compost networks
Saprotrophic fungi unlock lignin and cellulose. A sterile heap stays a pile of sticks.
Indoor damp
Black-stained bathrooms are often Cladosporium or similar. Fix leaks before buying a stronger scent.
Mushroom markets
Button, shiitake and oyster mushrooms are farmed fruiting bodies. Wild picking needs local expertise this page cannot supply.
Antibiotics origin story
The penicillin lineage began as a mould contaminant. Modern supply is industrial fermentation, not a windowsill protocol.
Respect water, wood and time — that is where unwanted indoor growth actually happens.
Keep exploring
More in Tree of microbes
Bacteria
Single-celled prokaryotes with cell walls ? the oldest widespread life form, and both partners and pathogens.
Familiarity 95Viruses
Packets of DNA or RNA that are not cells — they replicate only inside living hosts.
Familiarity 96Archaea
A prokaryotic domain that is not bacteria — methanogens, extremophiles and no known human pathogens.
Familiarity 35Bacteriophages
Viruses that infect bacteria — Earth's most abundant biological entities, and a concept-level idea in medicine.
Familiarity 42Protozoa
Motile unicellular eukaryotes — a teaching grade that includes pond ciliates and a minority of serious parasites.
Familiarity 58