, Volume 133, Issue 2, pp 111–126 | Cite as

Variation in setal micromechanics and performance of two gecko species

  • Travis J. Hagey
  • Jonathan B. Puthoff
  • Madisen Holbrook
  • Luke J. Harmon
  • Kellar Autumn
Original Paper


Biomechanical models of the gecko adhesive system typically focus on setal mechanics from a single gecko species, Gekko gecko. In this study, we compared the predictions from three mathematical models with experimental observations considering an additional gecko species Phelsuma grandis, to quantify interspecific variation in setal micromechanics. We also considered the accuracy of our three focal models: the frictional adhesion model, work of detachment model, and the effective modulus model. Lastly, we report a novel approach to quantify the angle of toe detachment using the Weibull distribution. Our results suggested the coupling of frictional and adhesive forces in isolated setal arrays, first observed in G. gecko is also present in P. grandis although P. grandis displayed a higher toe detachment angle, suggesting they produce more adhesion relative to friction than G. gecko. We also found the angle of toe detachment accurately predicts a species’ maximum performance limit when fit to a Weibull distribution. When considering the energy stored during setal attachment, we observed less work to remove P. grandis arrays when compared with G. gecko, suggesting P. grandis arrays may store less energy during attachment, a conclusion supported by our model estimates of stored elastic energy. Our predictions of the effective elastic modulus model suggested P. grandis arrays to have a lower modulus, E eff, but our experimental assays did not show differences in moduli between the species. The considered mathematical models successfully estimated most of our experimentally measured performance values, validating our three focal models as template models of gecko adhesion (see Full and Koditschek in J Exp Biol 202(23):3325–3332, 1999), and suggesting common setal mechanics for our focal species and possibly for all fibular adhesives. Future anchored models, built upon the above templates, may more accurately predict performance by incorporating additional parameters, such as variation in setal length and diameter. Variation in adhesive performance may affect gecko locomotion and as a result, future ecological observations will help to determine how species with different performance capabilities use their habitat.


Frictional adhesion Work of detachment Effective elastic modulus Weibull distribution Toe detachment angle Template model 



We thank four previous anonymous reviewers, Craig McGowan, Mitch Day, Chloe Stenkamp-Strahm, the Harmon, Rosenblum, and Autumn labs for helpful advice and comments, Matt Wilkinson for assistance with laboratory equipment, Katie Pond and Christine Van Tubbe for help with animal care, Meghan Wagner and Andrew Schnell for assistance in the laboratory, and the University of Idaho IACUC for approval of the project (Protocol #2010-40). Aaron Bauer and Todd Jackman also provided assistance and support. We thank the University of Idaho and the National Science Foundation (DEB-0844523, IOS-0847953 and NBM-0900723) for funding.


  1. Alibardi L, Toni M, Dalla Valle L (2007) Expression of beta-keratin mRNAs and proline uptake in epidermal cells of growing scales and pad lamellae of gecko lizards. J Anat 211(1):104–116PubMedCentralPubMedCrossRefGoogle Scholar
  2. Autumn K, Liang YA, Hsieh ST, Zesch W, Chan WP, Kenny TW, Fearing R, Full RJ (2000) Adhesive force of a single gecko foot-hair. Nature 405(6787):681–685PubMedCrossRefGoogle Scholar
  3. Autumn K, Sitti M, Liang YA, Peattie AM, Hansen WR, Sponberg S, Kenny TW, Fearing R, Isrealachvili JN, Full RJ (2002) Evidence for van der Waals adhesion in gecko setae. Proc Natl Acad Sci USA 99(19):12252–12256PubMedCentralPubMedCrossRefGoogle Scholar
  4. Autumn K, Dittmore A, Santos D, Spenko M, Cutkosky M (2006a) Frictional adhesion: a new angle on gecko attachment. J Exp Biol 209(18):3569–3579PubMedCrossRefGoogle Scholar
  5. Autumn K, Majidi C, Groff RE, Dittmore A, Fearing R (2006b) Effective elastic modulus of isolated gecko setal arrays. J Exp Biol 209(18):3558–3568PubMedCrossRefGoogle Scholar
  6. Bauer AM (1998) Morphology of the adhesive tail tips of carphodactyline geckos (Reptilia: Diplodactylidae). J Morphol 235(1):41–58CrossRefGoogle Scholar
  7. Chen B, Wu PD, Gao H (2008) Hierarchical modelling of attachment and detachment mechanisms of gecko toe adhesion. Proc R Soc A 464(2094):1639–1652CrossRefGoogle Scholar
  8. Chen B, Wu P, Gao H (2009) Pre-tension generates strongly reversible adhesion of a spatula pad on substrate. J R Soc Interface 6(35):529–537PubMedCentralPubMedCrossRefGoogle Scholar
  9. Elstrott J, Irschick DJ (2004) Evolutionary correlations among morphology, habitat use and clinging performance in Caribbean Anolis lizards. Biol J Linn Soc 83(3):389–398CrossRefGoogle Scholar
  10. Federle W (2006) Why are so many adhesive pads hairy? J Exp Biol 209(14):2611–2621PubMedCrossRefGoogle Scholar
  11. Full RJ, Koditschek DE (1999) Templates and anchors: neuromechanical hypotheses of legged locomotion on land. J Exp Biol 202(23):3325–3332PubMedGoogle Scholar
  12. Gamble T, Greenbaum E, Jackman TR, Russell AP, Bauer AM (2012) Repeated origin and loss of adhesive toepads in geckos. PLoS ONE 7(6):e39429. doi: 10.1371/journal.pone.0039429
  13. Glaw F, Vences M (2007) A field guide to the amphibians and reptiles of Madagascar. 3rd edn. Köln, Vences & Glaw, Köln, GermanyGoogle Scholar
  14. Glossip D, Losos JB (1997) Ecological correlates of number of subdigital lamellae in anoles. Herpetologica 53(2):192–199Google Scholar
  15. Gravish N, Wilikinson M, Autumn K (2008) Frictional and elastic energy in gecko adhesive detachment. J R Soc Interface 5(20):339–348PubMedCentralPubMedCrossRefGoogle Scholar
  16. Hagey TJ (2013) Mechanics, diversity, and ecology of Gecko adhesion. University of Idaho, MoscowGoogle Scholar
  17. Hansen WR, Autumn K (2005) Evidence for self-cleaning in gecko setae. Proc Natl Acad Sci USA 102(2):385–389PubMedCentralPubMedCrossRefGoogle Scholar
  18. Hecht MK (1952) Natural selection in the lizard genus Aristelliger. Evolution 6(1):112–124CrossRefGoogle Scholar
  19. Huber G, Gorb SN, Hosoda N, Spolenak R, Arzt E (2007) Influence of surface roughness on gecko adhesion. Acta Biomater 3(4):607–610PubMedCrossRefGoogle Scholar
  20. Irschick DJ, Austin CC, Petren K, Fisher RN, Losos JB, Ellers O (1996) A comparative analysis of clinging ability among pad-bearing lizards. Biol J Linn Soc 59(1):21–35CrossRefGoogle Scholar
  21. Irschick DJ, Herrel A, Vanhooydonck B (2006) Whole-organism studies of adhesion in pad-bearing lizards: creative evolutionary solutions to functional problems. J Comp Physiol A 192(11):1169–1177CrossRefGoogle Scholar
  22. Johnson MK, Russell AP (2009) Configuration of the setal fields of Rhoptropus (Gekkota: Gekkonidae): functional, evolutionary, ecological and phylogenetic implications of observed pattern. J Anat 214(6):937–955PubMedCentralPubMedCrossRefGoogle Scholar
  23. Losos JB (2009) Lizards in an evolutionary tree: the ecology of adaptive radiation in anoles. University of California Press, BerkeleyGoogle Scholar
  24. Maderson PFA (1964) Keratinized epidermal derivatives as an aid to climbing in gekkonid lizards. Nature 203(4946):780–781CrossRefGoogle Scholar
  25. McCool JI (2012) Using the Weibull distribution: reliability, modeling and inference, vol 950. Wiley, LondonCrossRefGoogle Scholar
  26. Peattie AM (2007) The function and evolution of Gekkotan adhesive feet. Doctor of Philosophy, University of California, BerkeleyGoogle Scholar
  27. Peattie AM (2009) Functional demands of dynamic biological adhesion: an integrative approach. J Comp Physiol B 179(3):231–239PubMedCrossRefGoogle Scholar
  28. Persson BNJ (2003) On the mechanism of adhesion in biological systems. J Chem Phys 118(16):7614–7621CrossRefGoogle Scholar
  29. Pesika NS, Gravish N, Wilkinson M, Zhao B, Zeng H, Tian Y, Israelachvili J, Autumn K (2009) The crowding model as a tool to understand and fabricate gecko-inspired dry adhesives. J Adh 85(8):512–525CrossRefGoogle Scholar
  30. Pugno NM, Lepore E (2008a) Observation of optimal gecko’s adhesion on nanorough surfaces. BioSystems 94(3):218–222PubMedCrossRefGoogle Scholar
  31. Pugno NM, Lepore E (2008b) Living Tokay geckos display adhesion times following Weibull statistics. J Adh 84(11):949–962CrossRefGoogle Scholar
  32. Puthoff JB, Prowse MS, Wilkinson M, Autumn K (2010) Changes in materials properties explain the effects of humidity on gecko adhesion. J Exp Biol 213(Pt 21):3699–3704PubMedCrossRefGoogle Scholar
  33. Pyron RA, Burbrink FT, Wiens JJ (2013) A phylogeny and revised classification of Squamata, including 4161 species of lizards and snakes. BMC Evol Biol 13(1):93PubMedCentralPubMedCrossRefGoogle Scholar
  34. Rosler H, Bauer AM, Heinicke MP, Greenbaum E, Jackman T, Nguyen TQ, Ziegler T (2011) Phylogeny, taxonomy, and zoogeography of the genus Gekko Laurenti, 1768 with the revalidation of G. reevesii Gray, 1831 (Sauria: Gekkonidae). Zootaxa 2989:1–50Google Scholar
  35. Ruibal R, Ernst V (1965) The structure of the digital setae of lizards. J Morphol 117(3):271–293PubMedCrossRefGoogle Scholar
  36. Russell AP (1977) Genera Rhoptropus and Phelsuma (Reptilia Gekkonidae) in Southern-Africa—case of convergence and a reconsideration of biogeography of Phelsuma. Zool Afr 12(2):393–408Google Scholar
  37. Russell AP (1979) Parallelism and integrated design in the foot structure of gekkonine and diplodactyline geckos. Copeia 1979(1):1–21CrossRefGoogle Scholar
  38. Russell AP (2002) Integrative functional morphology of the gekkotan adhesive system (Reptilia: Gekkota). Integr Comp Biol 42(6):1154–1163PubMedCrossRefGoogle Scholar
  39. Russell AP, Higham TE (2009) A new angle on clinging in geckos: incline, not substrate, triggers the deployment of the adhesive system. Proc R Soc B 276(1673):3705–3709PubMedCentralPubMedCrossRefGoogle Scholar
  40. Russell AP, Johnson MK (2007) Real-world challenges to, and capabilities of, the gekkotan adhesive system: contrasting the rough and the smooth. Can J Zoolog 85(12):1228–1238CrossRefGoogle Scholar
  41. Spezzano LC Jr, Jayne BC (2004) The effects of surface diameter and incline on the hindlimb kinematics of an arboreal lizard (Anolis sagrei). J Exp Biol 207(Pt 12):2115–2131PubMedCrossRefGoogle Scholar
  42. Tian Y, Pesika N, Zeng H, Rosenberg K, Zhao B, McGuiggan P, Autmn K, Israelachvili J (2006) Adhesion and friction in gecko toe attachment and detachment. Proc Natl Acad Sci USA 103(51):19320–19325PubMedCentralPubMedCrossRefGoogle Scholar
  43. Williams EE, Peterson JA (1982) Convergent and alternative designs in the digital adhesive pads of Scincid lizards. Science 215(4539):1509–1511PubMedCrossRefGoogle Scholar
  44. Yamaguchi T, Gravish N, Autumn K, Creton C (2009) Microscopic modeling of the dynamics of frictional adhesion in the gecko attachment system. J Phys Chem B 113(12):3622–3628PubMedCrossRefGoogle Scholar
  45. Yang ZL, Xie M (2003) Efficient estimation of the Weibull shape parameter based on a modified profile likelihood. J Stat Comput Simul 73(2):115–123CrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  1. 1.Department of Biological SciencesUniversity of IdahoMoscowUSA
  2. 2.Biology DepartmentLewis & Clark CollegePortlandUSA

Personalised recommendations