Meeting Abstract
P3.55 Thursday, Jan. 6 Flipping Through Penguin Flippers: An Ecomorphological Approach JORDAN, Laura K.*; CHIARADIA, André C.; SIMPSON, Ken N.G.; ROPERT-COUDERT, Yan; Florida Atlantic University; Phillip Island Nature Park; Victorian Ornithological Research Group; Institut Pluridisciplinaire Hubert Curien laurakjordan@gmail.com
Wing, flipper, and fin shapes have strong influences on flight and swimming efficiency. Understanding this influence may help reveal conditions in which animals have evolved. Penguins (Spheniscidae) have replaced large aerial wings with short powerful flippers, however, little is known about variation in flipper shape among species. This family demonstrates a variety of ecological differences spanning from Antarctica to the equator and species differ in migratory patterns, diving behavior and foraging strategies. This work represents the first study to describe and compare the aspect ratio of penguin flippers from all extant penguin species. We also compare methods of determining flipper area and include analysis of both preserved and live penguin flippers. Flipper aspect ratio is similar for most species (4.0 to 4.5); however, we found higher aspect ratios than previously documented in four penguins species ranging up to 5.7. Both evolutionary and ecological factors may be related to penguin flipper shape and higher aspect ratio may enhance diving capabilities. Image analysis is a more precise yet more time consuming method of calculating flipper area. Using flipper length and width hand measurements to calculate area results in an underestimate of aspect ratio. We provide a correction factor to improve accuracy of calculations from hand measurements, which may be taken more easily in the field. Finally, we find that with dry skin preservation, flippers become narrower and slightly shorter than the flippers of live penguins. The aspect ratios compared here across all penguin species are based on uncorrected length and width measurements of dry preserved specimens, therefore aspect ratios are expected to be even higher in live animals, as seen in the four live species included in this study.
