

The same goes for everything that lives then. There is no such thing as a mammal, they are just a form of prototheria! A lot of them just evolved into what we consider marsupials or eutheria. But a koala is just as much a mammal as a lemur!
Now this is a much smaller branch ofc, but you could slap it onto anything more vague. Reptiles, fish, crabs… and worse… fungi. Not to mention the archea.
Depends. I had 4 at 90°. Only one hurt a little. They caused pockets, which are hard to clean (impossible by yourself) and can accelerate bone loss. I removed 3 of them. 2 by a jaw surgeon. They were creating a space bewteen molars deeper inside the bone, while also creating an opening at the top. Nasty.
Chronic inflamation of the gums don’t hurt either. Best way to tell is by a mouth hygiënist. If your gums bleed easily while flossing, it’s a good idea to keep flossing. Takes about 1-2 weeks before the gums calm down and the swelling dissipates. I use those tiny round brushes to get in between. If you start using those, m start with the thinnest wire. The metal should absolutely not scrape against the teeth, only the brush.
Taken years to form that habit…