That concept (populations which can share genes) is for species which have sexual reproduction. For populations which require special conditions, you can talk a

That concept (populations which can share genes) is for species which have sexual reproduction. For populations which require special conditions, you can talk about subspecies. But not for the rest of lifeforms. Bacteria reproduce by cloning themselves and they can share genes laterally (between adults). And viruses are really more similar to computer viruses with intended replication errors than a lifeform.