The relationship is not symbiotic, but parasitic, and can range from severe to unnoticeable. Think about it : (hypothetically) you could have lice or ringworm, and yes your body might try to combat this but not very hard because it doesn't really affect you over all. Your body also contains bacteria like Eshcerichia Coli which your body needs but can also be fatal. You could also some parasites or even worms in your body - they eat some of your food, maybe drink some of your blood, but they don't affect your body enough to kill you. You could also have a tapeworm - a much, much more severe parasite, that could kill you.
Just as snakes could have pin worms, and in the wild these won't affect a snake too much negatively, or a snake could have a tapeworm and die from it.
It's all relative and dependant on external factors such as food supply, climate, and stress.
Last edited by Zoe; 06-30-03 at 10:36 AM..