The physical world is teeming with life. There are millions of different life forms on our planet and who knows how many more on other planets. And what about the life forms that are not considered living like rocks, rivers, etc. Maybe we should think of planets, moons, and stars as life forms also. But what about the spiritual worlds? Are they as full of life as the physical world? Absolutely! Since no physical thing can exist without a spirit, every life form in the physical world has a corresponding spirit. In addition, there are living things that exist only in spirit form; no physical body at all. So the number of life form in the spiritual worlds exceeds the number in the physical world. But what about the diversity of life forms? 
    Are there as many different life forms in the spiritual worlds as there are in the physical? That question is harder to answer. When we try to think of what life forms live in the spirit worlds, all we can usually come up with is angels and demons. Within angels and demons though, there is more than one type. I know some world scriptures categorize angels, but I don't know of any that categorize the demons, yet we know there is more than one type. But is there anything other than angels and demons? Probably. We may not know what they are, but it is likely that many different life forms do exist in the spiritual worlds, although probably not as many as physical forms. I say that because we know from St. Francis, who apparently could see the spirits of various living things, that the spirits of animals and plants were so much like human spirits, at least in his eyes, that he started calling animals and plants his brothers and sisters.