Arizona Governor Jan Brewer might have titled her book “Scorpions for Breakfast,” but the grasshopper mouse really does eat them. Scorpions of the genus Centruroides are particularly deadly. The venom of the Arizona bark scorpion (Centruroides sculturatus, formerly known as Centruroides exilicauda) contains toxins that can kill a young child or a vulnerable adult.
The venom of the bark scorpion acts on what are called ion channels. Ion channels are involved in the conduction of nerve impulses in the body. These channels normally open or close, in response to a signal in the nervous system. Bark scorpion toxin blocks these channels, and as a result they get “stuck” in the on position. This causes pain and a variety of other unpleasant neurological effects including neuromotor hyperactivity (tossing and turning), eye muscle and visual abnormalities, breathing problems and sometimes heart problems.
The grasshopper mouse has evolved alongside the bark scorpion, developing an immunity to the bark scorpion venom. As a result, the grasshopper mouse can eat scorpions with little or no adverse effect.
For more on the grasshopper mouse, go to: http://www.usatoday.com/story/news/nation/2013/10/24/mouse-scorpion-arizon/3172901/
For more on the Arizona bark scorpion, go to: http://www.desertmuseum.org/kids/oz/long-fact-sheets/Bark%20Scorp.php
