This seems like a rabbit whole, at some point there's no objective ethics, you pick your line. Are you going to include bacteria, yeast, common viruses, dust mites, there's plenty to choose from.
I think one thing that seems relevant to humans, is we seem to be bothered only once we can relate to the other being in a more explicit way. This is true even between our peers. Maybe as we understand more and more of other creatures so will our empathy.
I think one thing that seems relevant to humans, is we seem to be bothered only once we can relate to the other being in a more explicit way. This is true even between our peers. Maybe as we understand more and more of other creatures so will our empathy.