by Anne A. Mad­den — Many plants do not want to be eaten. They avoid this fate by pro­duc­ing deadly tox­ins and car­cino­genic poi­sons, such as those as­so­ci­ated with the aptly named poi­son ivy, poi­son sumac, and deadly night­shade. De­spite such de­fenses, al­most half of all an­i­mal species...