Its host, Zamia pumila is laced with the toxic secondary plant chemical cycasin with greatest concentrations in the new foliage favored by atala larvae. As it feeds the larva stores the cycasin in its tissues. The cycasin is retained throughout the pupal and adult stages rendering all three stages distasteful and toxic to predators. In adult atalas, the cycasin is distributed equally between the body and wings. The appearance and biology of the atala are typical of many chemically defended insects.
Most aposematic insects advertise the fact that they are dangerous with bright contrasting colors.
Also, they often are found in aggregations. It is likely that the bright red-orange scales that are placed around the atala eggs and possibly the eggs themselves contain cycasin. By aggregating, the bright red-orange and yellow larvae enhance their warning coloration. A predator tasting one of them will most likely leave the others alone. Even the slow flight of adults and their reluctance to fly when disturbed are characteristic of many aposematic insects.