Fungi are among the most widespread Eukaryotes on the planet, and yet are often overlooked, despite their incredible diversity. They're more closely related to humans than to plants, many species can just as easily be single cells of yeast growing in bread as thread-like hyphae creeping through the earth, and some individuals can extend for miles, invisible to us. But one especially interesting aspect of fungi is their relationship to other types of life. As heterotrophs, all species of fungi get their food from other organisms, but their strategies vary wildly. They can be necrotrophs, killing other organisms for food, or saprotrophs, feeding on fallen logs and rotten detritus, or biotrophs, parasitically feeding off of other life. But as diverse as their strategies are the organisms they interact with.
Eukaryotes consist of 5 widely-accepted kingdoms: Protozoa, Chromista, Plants, Animals, and Fungi. The relationships between fungi and other eukaryotes can be symbiotic, predatory, competitive, or something else, but I want to focus on mutualism, where the fungi and symbiont both improve the other's survival and reproductive success. Here, I will only go over plants and animals, as those groups are the most well-studied and best understood. But be aware that the connections detailed below are only a small slice of the complex connections between fungi and their symbionts. There is a vast amount of connections that I haven't come across, as well as those that remain undiscovered.
All pixel art was created by me. The other images are taken from Wikimedia Commons, and sourced accordingly.
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