Supplementary Material: "Critical Crack Length as an Evolutionary Constant in Odonata Wing Venation: Lessons from Fossils"

This dataset contains quantitative measurements of wing cell geometry in fossil Odonata, used to investigate the evolutionary stability of cellular structures in insect wings. A total of 69 fossil wings from 22 extinct taxa, spanning the Jurassic to the Miocene, were analyzed using the automated segmentation tool WingSegment. Cell-length distributions were extracted and compared with published data from extant dragonflies and damselflies. The results show that fossil wings exhibit a dominant cell-size range of 0.5-1.5 mm, consistent with extant species, despite differences in age, environment, and wing size. This supports the hypothesis that wing cell size is constrained by a mechanically critical length scale related to damage tolerance. The dataset provides evidence that this structural principle has remained stable over evolutionary time and may inform the design of bio-inspired lightweight materials.