This was 60 million years older than any known fungal fossil. At least 180,000 species that have been identified, but this is probably just the thawed surface of the tip of the iceberg. There may be as many as four million species of fungi that are unknown. Then again, researchers are not always certain what a fungal species is, that is, where to draw the line between different morphological forms or biochemical types. Really, there is more than a little discussion about what constitutes a fungal individual.
Many fungi are easy to culture, and have biochemical similarities to animals.
The first genome sequenced from a eukaryote was that of Saccharomyces cerevisiae , a yeast in the Ascomycota . All the ge nes known from this fungus are now available on a commercially available genomic array or ' gene chip' allowing researchers to determine exactly which proteins are produced as fungi go through their life cycles, or as they encounter various environmental factors. Fungi are very different from either plants or animals. They live in extreme environments from sandstone layers in Antarctica to the driest desserts. They often live in intimate association with algae, plants, or animals, which leads to interesting questions about coevolution .