One reason for this discrepancy is that few data on fungi are available from the tropics. This clearly differentiates the Eumycota from true plants which have cell walls strengthened with cellulose. Fungi contribute more biomass to soil than any other organisms. They help to bind soil particles. Many are saprophytes, obtaining nutrition from dead plant and animal remains and so playing a vital role in decomposition and recycling nutrients.
Fungi are of immense importance in the pharmaceutical industry.
Virtually all antibiotics, notably penicillin, are derived from fungi. Also, yeasts are the basis of the baking, brewing and wine-making industries. Relatively few of the larger fungi are poisonous, although those that are can be highly toxic. Some moulds growing on foodstuffs produce toxins that can cause tumours and other long-term medical problems. Widespread in the Northern Hemisphere, Fly Agaric may have been taken as long as 3500 years ago.