What are Fungi?

FUNGI ARE EVERYWHERE but they are easy to miss. They are inside you and around you. They sustain you and all that you depend on. As you read these words, fungi are changing the way that life happens, as they have done for more than a billion years. They are eating rock, making soil, digesting pollutants, nourishing and killing plants, surviving in space, inducing visions, producing food, making medicines, manipulating animal behavior, and influencing the composition of the Earth’s atmosphere. Fungi provide a key to understanding the planet on which we live, and the ways that we think, feel, and behave. Yet they live their lives largely hidden from view, and over ninety percent of their species remain undocumented. The more we learn about fungi, the less makes sense without them.

Several fungi produce dangerous substances called toxins, which if eaten via contaminated food – can be fatal to man and other animals. This is particularly a problem in developing countries where crop contamination can result in severe famine – or if eaten gives rise to various forms of cancer including liver cancer. Contamination of corn with one toxin called aflatoxin, produced by the fungus Aspergillus flavus, costs farmers in the U.S. alone – $100 million annually.

In humans fungi cause relatively minor skin infections such as ringworm and athlete’s foot, but several types of fungi – whose spores are carried around in the air we breathe – also cause several deadly diseases which can be hard to treat. These types of fungi are not generally visible to the naked eye – but it is their airborne spores which can cause illness. Fungi that can cause life-threatening infections in people include Aspergillus fumigatus, and other Aspergillus species, Candida albicans and Cryptococcus neoformans.