The nightshade family are all toxic to most animals and people. That family includes potatoes, tomatoes, peppers, eggplants, tomatillos, and, I believe, thorn apple (datura—usually seem as a large weed with very large, white, trumpet-shaped flowers). Affects range mild to lethal, though the fruits of tomato, pepper, eggplant, and tomatillo plants are not toxic. Potatoes are toxic if they are exposed to the sun during growth and develop green coloring. I once read (here maybe) of someone who pulled a bunch of tomato horn worms off of his tomato vines and fed them to his chickens, who devoured them, but were all dead the next day. So I’m not sure that eating bugs and caterpillars that have been eating nightshades is safe.