Talk:Meroune Lorelei/@comment-172.56.3.146-20150103203307/@comment-26824352-20150802004955

Presence of gills does not immediately make them non-mammalian, but is pretty damning evidence against it.

However, lamiae and lizard folk aren't totally mammals, either. If you're describing mammals by presence of breasts, all liminals fit that bill, but they're all probably closer to pseudomammals. As for breeding with humans, it would seem to be some strange variant on parthenogenesis, though with a few marked differences.

In the case of the centaurs, it would seem that the only real issue is the size of the equipment, as the genetic viability is already proven. And as far as that goes there are people in the real world who screw horses, so it isn't impossible. I would imagine it'd be rather uncomfortable if you weren't particularly into that sort of thing, though.