Puddling in butterflies: current knowledge and new directions.

This article reviews the behavior of puddling in butterflies and moths, where individuals aggregate on mineral-rich substrates to supplement micronutrients—primarily sodium and nitrogen—lacking in their typical adult diets. It synthesizes current knowledge on the nutritional benefits of puddling, its social dynamics, sensory cues used for site detection, and variation across species, sexes, and regions, highlighting a strong male bias in puddling behavior linked to reproductive advantages such as nutrient transfer via spermatophores. The review also discusses differences between temperate and tropical species in nutrient preferences and puddling patterns, as well as the less-studied puddling behavior in moths, which may rely more on olfactory cues due to nocturnal activity. Key gaps identified include the mechanisms of puddle detection, ecological and evolutionary drivers of taxonomic variation, and the influence of environmental factors, suggesting directions for future research.