Are there any species of parasitic bacteria? Or, when you go down that small/to their level, does the classification as a "parasite" start to break down and not really be applicable?
reddit.comu/MaggieLinzer — 14 hours ago
(In other words,) I know what causes animals to evolve, and why they can stop evolving significantly after millions of years, but what causes some animal species to not evolve FOR millions of years?