One of the groups (DPANN) is I believe invariably symbiotic, which made it hard to find through traditional methods. It may shed light on how eukaryotes got sta

One of the groups (DPANN) is I believe invariably symbiotic, which made it hard to find through traditional methods. It may shed light on how eukaryotes got started. A kind of fascinating problem in microbiology is that prokaryotes didn't take high school science and don't realize you can't acquire traits, you can only inherit them. So they trade genetic material with each other like Pokemon cards in a process called "horizontal gene transfer". This makes it considerably harder to figure out what 'species' even means.