Anyone who doesn't believe this needs to look up "rattlesnake bite" on google images. (Warning: graphic, of course) That said, it's usually possible to avoid

Anyone who doesn't believe this needs to look up "rattlesnake bite" on google images. (Warning: graphic, of course) That said, it's usually possible to avoid getting bitten if you know what to look for and what to do. They're generally willing to just slither in the other direction unless they're being threatened, but that doesn't really help if you, for example, accidentally step on one on the trail.