DOI: 10.5061/dryad.63xsj3v9v
title: Data from: Biomechanical drivers of the evolution of butterflies and moths with a coilable proboscis

description: The ability of butterflies and moths to drink nectar through a proboscis
 up to 3 times longer than their body has remained a puzzle. Although
 current biomechanical models suggest that the proboscis is used as a
 straw, the forces required to pull liquids through these long straws would
 require adaptations that have not yet been described, such as
 disproportionately large muscles that create strong pressure
 differentials. Our analyses revealed a common feature that allows
 butterflies and moths to drink through an elongated proboscis: the
 presence of bubble trains in the conduits of the feeding system. We
 combined X-ray phase-contrast imaging, optical video microscopy,
 micro-computed tomography, phylogenetic models of evolution, and fluid
 mechanics models of bubble train formation to understand the biomechanics
 of butterfly and moth feeding. Our models of evolution suggest that the
 bubble train mechanism appeared in the early evolution of butterflies and
 moths with a proboscis long enough to coil. We propose that the bubble
 train mechanism is a key feature in the diversification of butterflies and
 moths with a coilable proboscis.
description: The data collected to characterize the sucking pump and
 associated muscles were taken from micro-tomography scans in the software
 Slicer 3D. 
description: # Biomechanical drivers of the evolution of butterflies and moths with a
 coilable proboscis
 [https://doi.org/10.5061/dryad.63xsj3v9v](https://doi.org/10.5061/dryad.63xsj3v9v) ## Description of the data and file structure ##### Data: The main data retrieved for this paper comes from micro-tomography scans of hawkmoths. In these scans, we measured relevant sucking pump characteristics aiming to describe the biomechanical drivers of drinking nectar in hawkmoths. You will note in the dataset that the species from lines 2-23 have information on all columns: these were the species we scanned ourselves. Species in lines 24-34 were taken from Reinwald et al. (2022, full reference below), and species in lines 35-40 were taken from Bauder et al. (2013, full reference below).  For more details on why we chose these variables and how we measured them, please refer to the paper.  The phylogeny used came from Kawahara & Barber (2015, full reference below). References: * Bauder, J. A. S.; Handschuh, S.; Metscher, B. D.; Krenn, H. W., Functional morphology of the feeding apparatus and evolution of proboscis length in metalmark butterflies (Lepidoptera: Riodinidae). Biological Journal of the Linnean Society 2013, 110 (2), 291-304.\ * Reinwald, C.; Bauder, J. A. S.; Karolyi, F.; Neulinger, M.; Jaros, S.; Metscher, B.; Krenn, H. W., Evolutionary functional morphology of the proboscis and feeding apparatus of hawk moths (Sphingidae: Lepidoptera). Journal of Morphology 2022, 283 (11), 1390-1410. \ * Kawahara, A. Y.; Barber, J. R., Tempo and mode of antibat ultrasound production and sonar jamming in the diverse hawkmoth radiation. Proceedings of the National Academy of Sciences of the United States of America 2015, 112 (20), 6407-6412. ##### Acknowledgments: This work was supported by National Science Foundation grant IOS 2042937. Use of the Advanced Photon Source, an Office of Science User Facility operated for the U.S. Department of Energy (DOE) Office of Science by Argonne National Laboratory, was supported by the U.S. DOE under Contract no. DE-AC02-06CH11357; we thank Dr. Wah Keat Lee and Dr. Taras Andrukh for helping with protocol development and X-ray imaging. The work of P.H.A. was partially supported by NIFA/USDA under project number SC-1700596 and is Technical Contribution No. 7290 of the Clemson University Experiment Station. We thank Jayma Moore and North Dakota State University Electron Microscopy Core Lab in Fargo, ND, USA, for micro-computed tomography of hawkmoths. We thank Julia Bauder and Harald Krenn for providing the extended set of data from15. We also thank James & Dawn Langiewicz for allowing us to use their beautiful photo in Figure 1. ### Files and variables #### File: Sucking\_pump-data.csv **Description:**  ##### Variables METADATA OF Sucking_pump-data.csv In the columns we have the variables, in rows we have the species. * COLUMN A: species – the scientific name of the species measured.  * COLUMN B: proboscis.length – length of the proboscis of the species. Measured on the CT-scans or taken from the papers in which the data were retrieved from. Unit: mm. * COLUMN C: proboscis.diam – diameter of the proboscis. Measured as the distance between the lateral sides of the proboscis. Measured on the slices, rather than the 3D volume. Species with missing values denote the species we did not have the data for and were discarded in the analysis. Unit: mm.  * COLUMN D: muscle.volume - volume of the dilator muscles associated to the sucking pump. Measured on the CT-scans. Unit: mm^3. * COLUMN E: inside.pump.volume - volume of the buccal chamber. Measured on the CT-scans. Missing values denote the species for which we did not have the scans and the original paper did not measure the variable. Unit: mm^3. * COLUMN F: food.canal.volume – volume of the food canal running inside the proboscis. Species that have zero (0) as a value mean that the galeae (the units that come together to form the proboscis) are not united and the species putatively does not feed. Measured on the CT-scans. Unit: mm^3. * COLUMN G: pump.volume – volume of the compressor muscle associated with the sucking pump. Measured on the CT-scans. Unit: mm^3. * COLUMN H: body.length – wingspan of the species. Taken from the average size of the species collected on the field (we did not measure the scanned individuals because of our preservation procedures). Missing values denote the species for which we did not have the scans and the original paper did not measure the variable. Unit: mm. * COLUMN I: sp.in.tree - name of the species in the file containing the phylogenetic tree. This is used solely to prune the tree more easily. NA denotes the butterfly species which are not present in the hawkmoth phylogenetic tree. * COLUMN J: subfamily - the subfamily the species belongs to. ## Code/software Micro-tomography scans were analyzed using Slicer 3D. All raw data was analyzed using R software with the packages shown in the paper.