Like other leafy liverworts, Hooker’s flapwort grows as a network of underground axes, or stem-like structures, that put out small, photosynthesizing shoots above the soil. Looking at these subterranean stems using an electron microscope, Duckett noticed a symbiotic fungus that he described as an “odd fungus that looked like nothing anyone had seen before.”
Duckett was curious about the fungus, so he teamed up with Martin Bidartondo, a molecular ecologist working at Kew Gardens. Initially Bidartondo was at a loss, reporting back that he couldn’t identify the fungus’s DNA. Eventually, using new techniques, he found that the mystery symbiont belonged to the Mucoromycotina, or “mucs,” an ancient lineage of fungi previously known only as free-living decomposers.
It's wild to me that most multicellular organisms are symbiotic with other kingdoms of life. Like, not only do mammals have gut microbiomes, we also have cerebrospinal fluid microbiomes! And how roots need fungi to break down the soil for them.
It's as if each creature is a mountain of its own, with its own flora and fauna ^-^