Like lizards, the more than 2,500 species of snakes owe much of their success to their highly mobile jaws that can be used to seize and swallow large prey.  In spite of the fact  that rarely do they pose any real threat to people in developed countries, snakes are often unjustly persecuted and deserve to be protected not only for the beneficial role they play in the control of rodent populations but also for the contribution they make to the Earth's biodiversity.  It is against the law in many countries (including most of the United States) to kill nonvenomous species and sometimes even venomous ones like the timber rattlesnake shown above, which is protected in Wisconsin!