When we think of nature, we like to think of cute things like blooming flowers or a chipmunk stuffing nuts in its cheek, but actually, nature is more like the boar god from Princess Mononoke: Festering with wormy slimy things.
Whenever I see drawings of, say, the bronchi in the lungs, I always get a creepy feeling, because it looks more like plant roots than something that should be inside of a human.
Cute and beautiful things make up a tiny portion of nature, and even they aren't cute inside.