Lord of the Wings: A Computational Toolbox for the Automated Processing and Geometric Analysis of Odonate Wings

Abstract

Insect wings have interested a surprisingly broad range of disciplines. Engineers explore the mechanical properties of insect wings for applications in microrobotics and aeronautics, and biologists tend to focus on the development, evolutionary history, and scaling relationships amongst insect wings. In order to collect detailed quantitative measurements of wings, these researchers have primarily used manual methods. In this paper, we develop tools to automate the extraction and analysis of the shape and arrangements of the structural components of insect wings. Specifically, our tools compute statistics for the shape and size of the transparent "cells" that are formed by the rigid cuticular struts called "veins." We calculate a range of characteristics, including edge number, size, and curvature for the wing cells of more than 10 wings from various species of dragonflies and damselflies. Our results provide insight into the mechanics of the wing and allow us to hypothesize rules that govern wing formation. Furthermore, our research also suggests that increased wing length tends to scale with increased number of cells and decreased average wing cell size, such that more of the wing's surface area is dominated by smaller cells. Developmental principles have been studied in detail for Drosophila melanogaster wings, and it is unknown whether these principles apply to other insects with more complex wing structures. Our observations enable us to hypothesize that there are geometrically distinct regions in the wing that are laid down in sequence. We have used these findings to make mathematically precise, testable predictions about how the patterns in dragonfly and damselfly wings develop.