If I could share only one photo with you from my recent expedition across Paraná, Brazil, it would be this one:

Male Orses cynisca feeding at saliva-soaked tissue paper. Iguaçu National Park, Paraná, Brazil. 31-I-2016. Photo by Andrew D. Warren.

There is so much science in this one photo!

First, this photo is of a skipper butterfly (family Hesperiidae), the group I have spent much of the past 20+ years researching (see my publications).  There are over 4000 species of skippers worldwide, although the greatest diversity of skipper species, by far, is in the New World tropics.

Second, this skipper, Orses cynisca, belongs to a group of skippers whose phylogenetic placement remains unclear- this genus and its relatives (Perichares, Lycas, Alera, etc.) may be more closely related to various Old World skippers than they are to any New World groups.

Third, this skipper has an extraordinarily long proboscis (straw-like ‘tongue’), indicating that it normally feeds at deep-tubed flowers.  Skippers such as this aren’t thought to be good pollinators; rather, they are nectar thieves (explained here)!

Fourth, this skipper is feeding at saliva-soaked tissue paper.  Attracting skippers (and other butterflies) this way is called the “Ahrenholz technique”. The tissue paper mimics bird poop, and the saliva is full of sodium and other nutrients that the butterflies seem to really like! The Ahrenholz technique works best around swarms of army ants (Eciton burchelli and Labidus praedator), which are followed by ‘ant birds’ that generate plenty of real bird poop (= skipper food), as they feast on the many insects fleeing from advancing army ant swarms. The main paper describing this phenomenon is here.

Fifth, the red eyes of this skipper are typical of species that are crepuscular. Crepuscular skippers tend to fly mainly at dawn and dusk, and on cloudy days with low light levels. When little or no biological information is known about a skipper, red eyes usually indicate that it is crepuscular.

Finally, the skipper’s posture and combination of colors resulted in a really beautiful photo- one of those rare pics that I knew would be awesome as soon as the shutter clicked.