DOI: 10.5061/dryad.905qfttpz
title: Data from: Strong attachment as an adaptation of flightless weevils on windy oceanic islands

description: Enhanced attachment ability is common in plants on islands to avoid
 potential fatal passive dispersal. However, whether island insects also
 have increased attachment ability remains unclear. Here we measured the
 attachment of a flightless weevil, Pachyrhynchus sarcitis kotoensis, from
 tropical islands, and compared it with documented arthropods from the
 mainland. We examined the morphology and material gradient of its
 attachment devices to identify the specific adaptive modifications for
 attachment. We find that the weevil has much stronger attachment force and
 higher safety factor than previously studied arthropods, regardless of
 body size and substrate roughness. This probably results from the specific
 flexible bases of the adhesive setae on the third footpad of the legs.
 This softer material on the setal base has not been reported hitherto and
 we suggest that it acts as a flexible hinge to form intimate contact to
 substrate more effectively. By contrast, no morphological difference in
 tarsomeres and setae between the weevil and other beetles is observed. Our
 results show the remarkably strong attachment of an island insect and
 highlights the potential adaptive benefits of strong attachment in windy
 island environment. The unique soft bases of the adhesive hairs may
 inspire the development of strong biomimetic adhesives.
description: # Data from: Strong attachment as an adaptation of flightless weevil on
 windy oceanic island The dataset belongs to Lu-Yi Wang1,2*, Chung-Ping
 Lin3*, Stanislav N. Gorb2*, Hamed Rajabi1,4* 1 School of Biosciences,
 Faculty of Science, The University of Melbourne, Melbourne, Australia 2
 Functional Morphology and Biomechanics, Institute of Zoology, Kiel
 University, Kiel, Germany 3 Department of Life Science, National Taiwan
 Normal University, Taipei, Taiwan 4 Division of Mechanical Engineering and
 Design, School of Engineering, London South Bank University, London, UK
 *Corresponding author: Lu-Yi Wang
 ([luyiwangtw@gmail.com](mailto:luyiwangtw@gmail.com),
 [luyiw@student.unimelb.edu.au](mailto:luyiw@student.unimelb.edu.au)),
 Chung-Ping Lin ([treehopper@ntnu.edu.tw](mailto:treehopper@ntnu.edu.tw)),
 Stanislav N. Gorb
 ([sgorb@zoologie.uni-kiel.de](mailto:sgorb@zoologie.uni-kiel.de)), Hamed
 Rajabi ([rajabijh@lsbu.ac.uk](mailto:rajabijh@lsbu.ac.uk)) This dataset
 includes 5 different components as listed below 1. centrifugal exp.csv 2.
 teneral.csv 3. weevil attachment.csv 4. compare with other arthropods.csv
 5. Weevil adhesion.Rmd ### centrifugal exp.csv The data from the
 centrigual experiment on the mature weevils. * type: The weevil is mature
 (hard) or newly enclosed (soft) * surface: Surface roughness the trial was
 performed on (entry: glass/s0.3/s3/s12; the value refers to the sand paper
 size, not the grain size. For grain size, see the paper.) * sex: Gender of
 the weevil (male/female/uncertain) * medium force: Medium force of the
 weevil from the five trials (unit: millinewton) * medium sf: Medium safety
 factor of the weevil from the five trials; Safety factor is calculated as
 medium force divided by the body weight of the weevil. (no unit) * id: The
 ID of the weevil * claw.condition: Whether the weevil's claws were
 intact or surgically removed (with claw/clawless) ### teneral.csv The data
 from the centrigual experiment on the teneral weevils * type: The weevil
 is mature (hard) or newly enclosed (soft) * surface: Surface roughness the
 trial was performed on (glass/s0.3/s3/s12) * sex: Gender of the weevil
 (male/female/uncertain) * medium force: Medium force of the weevil from
 the five trials (unit: millinewton) * medium sf: Medium safety factor of
 the weevil from the five trials; Safety factor is calculated as medium
 force divided by the body weight of the weevil. (no unit) * id: The ID of
 the weevil * claw.condition: Whether the weevil's claws were intact
 or surgically removed (with claw/clawless) ### weevil attachment.csv The
 data of the mature intact (with claws) weevil. This is the data format
 used to compare with other arthropods species surface force safety factor
 method. * order: The order of the weevil * species: species name *
 surface: Surface roughness the trial was performed on (entry:
 glass/s0.3/s3/s12; the value refers to the sand paper size, not the grain
 size. For grain size, see the paper.) * fore: Medium force of the weevil
 from the five trials (unit: millinewton) * safety factor: Medium safety
 factor of the weevil from the five trials; Safety factor is calculated as
 medium force divided by the body weight of the weevil. (no unit) * method:
 The methods used for measuring the attachment force (in this file, all are
 measured using centralfugal setup) ### compare with other arthropods.csv
 The attachment data of arthropods from literature for comparison with the
 mature weevils * order: The order of the arthropods * species: species
 name * surface: Surface roughness the trial was performed on * fore:
 Medium force of the arthropods from the literature (unit: millinewton) *
 safety factor: Safety factor of the arthropods from the literature. As it
 is calculated as force/weight, it is unit free. (no unit) * method: The
 methods used for measuring the attachment force (centralfugal
 setup/pull-off/traction force tester) ### Weevil adhesion.Rmd (uploaded to
 Zenodo) The Rmarkdown file for the statistical analyses and plotting in
 the manuscript.