RESUMO
Flower cues serve as information that improves foraging by flower visitors. These cues may act in a synergic, redundant or complementary way. We examined how the integration of visual cues affects foraging in the southern monarch butterfly, and whether these combined cues can be learned. Artificial flowers having two flower cues, colouration pattern (uniform or radial) and dimension (2D or 3D), were employed in laboratory experiments. We assumed that uniform flowers are less informative than radial ones, and that bi-dimensionality is less informative than tri-dimensionality. These cues resulted in four floral types (uniform 2D, radial 2D, uniform 3D and radial 3D). Two- and multiple choice tests were run to investigate whether butterflies show more attraction to more informative flowers than less informative ones. Flower cues acted in a complementary way, as more informative flowers were preferred by southern monarchs than less informative ones. In a multiple-choice scenario, uniform 2D flowers received less visits than radial flowers of both dimensions. In a second experiment, butterflies were conditioned to the four flower types. No conditioning occurred, as radial flowers were visited consistently more than uniform flowers. Our results show that southern monarchs take integrated flower information into account for foraging decisions, and that learning does not occur when highly informative flowers are present.