Cm. Penz et Hw. Krenn, Behavioral adaptations to pollen-feeding in Heliconius butterflies (Nymphalidae, Heliconiinae): An experiment using Lantana flowers, J INSECT B, 13(6), 2000, pp. 865-880
Butterflies in the genera Heliconius and Laparus obtain fitness-related ben
efits from using amino acids derived from pollen. These butterflies have mo
rphological features of the proboscis that facilitate pollen-feeding. Here
we investigate behavioral characteristics potentially involved in pollen-ga
thering. Analysis of four behavioral characters showed that pollen-feeding
species manipulate Lantana flowers faster and more thoroughly compared to n
on-pollen-feeding relatives. Although this suggests that pollen-feeding spe
cies are potentially more efficient in harvesting pollen, every butterfly t
ested successfully removed pollen from Lantana and non-pollen-feeding butte
rflies generally extracted larger amounts of pollen than Heliconius and Lap
arus. Morphological characteristics of the proboscis and the production of
abundant fluid exudate help keep pollen attached in the proboscis for long
periods of time-possibly key to Heliconius' and Laparus' ability to obtain
amino acids from pollen. Our results, in concert with those of previous mor
phological analysis, indicate that behavioral and structural attributes ass
ociated with pollen-feeding in Heliconius and Laparus are subtle modificati
ons of widespread butterfly characteristics and raise the question why othe
r butterflies do not use pollen in their diet.