Most wildlife is somewhat afraid of humans so long as they are not taught otherwise. They know you are big and don't know if you are going to eat them so they stay away. Mountain lions are the only possible exception. So long as you don't get close and don't give them reason to get close they will generally leave you alone.

The above is why it is critical to keep food either hung in a tree or in bear proof containers. So long as bears don't see humans and think "I've found food near them" they will stay away - but once they realize humans mean food there is trouble. Wild areas rarely have problems - causal campers don't realize how important proper bear protection is and over time bears have figured it out.

The black widow and a few other spiders and insects are exceptions - they will target you. (though mostly spiders leave you alone)