Hyenas have the strongest pound-for-pound jaws of any animal, you know what that means? It will crush your skull when it tries to and successfully kills you.
Think you're safe in the water? Ha, you stupid fool. The orca is the most dangerous animal in the world. I'm not sure if the Titanic ran into an iceberg; I'm pretty sure that an orca ran into it, and crushed the thing. Those people didn't die in the water, they died in an orca's stomach.
An ostrich kick can tear you from your pelvis to your sternum.
Even the animals that I could easily kill in combat will still find a way to kill me.
Sure a frog can't kill me, unless I eat it.
Maybe I could eat a random exotic Japanese fish, but that fish is poisonous and it will probably kill me.
In fact, pretty much any animal that I thought was not dangerous has some sort of venom in it that will kill me.
There are things in the water that will swim in your urethra and you'll have to have surgery to get it out.
At least small bugs like grasshoppers aren't dangerous, right? Wrong again. They will eat every crop around by having swarms in the billions and the fact that they can eat their body weight in a single day.
You can't crush a flea with your fingers.
At least with big animals, people will respect you for going out like a man. It's the small ones that scare the shit out of me. Go swimming in a river, and a worm will crawl into your eye. When it gets done making you blind, it will probably crawl back to your brain and kill you. Flies seem pretty harmless, except they can attack you in such a swarm to suffocate you. Well, at least ants aren't scary as you can just step on them. Oh yeah, one time a lady had surgery and while she was recovering from the anesthesia, ants ate out her eyeball and killed her.
So yeah, I highly recommend reading the book, because it's awesome, but I am now terrified of every living creature out there. So that's healthy.
P.S. Here's a guy on fire, because people on fire are far more interesting than people not on fire.