Butterfly, oh butterfly, how stinketh is thy palate?

. Butterflies are not the flower-loving insects that most everyone thinks. Most butterflies do not feed on flowers but on a variety of generally stinky substances containing high loads of bacteria and other microbes. Butterflies’ preferences for these substances can be broken down by taxonomy and gender. Males of most butterflies gather at wet spots on roads and stream beds to get salts and are especially drawn to fetid urine, while females are only occasionally observed engaging in this behavior. Rotten fruits on the forest floor are favorite gathering spots for butterflies, especially female nymphalids. Humans baiting butterflies find fermenting bananas and pineapple to be good substitutes for the natural forest fruits. Animal carcasses that are down to bones and fur and old fecal material are also extremely attractive to nymphalids, mostly males. Fermented fish or shrimp substitute quite well for carcasses and feces in traps. Most families of butterflies except Papilionidae and Pieridae can be collected with traps baited with fermented fruit and animal matter but there is disagreement about whether some of them are actually attracted to the bait or to the visual stimulus of the trap. Among those butterflies that feed at flowers, many are not there just for pollen and nectar but for various toxic materials in the nectar that they sequester and utilize for protection from predators. Little is understood about how these baits work including gender effects and attraction of Papilionidae and Pieridae to urine but not to rotten fruit or animal matter. Strong effects of elevation and geography also are not well understood.