Details

Autor(en) / Beteiligte

• Peisker, Henrik
• Michels, Jan
• Gorb, Stanislav N.

Titel

Evidence for a material gradient in the adhesive tarsal setae of the ladybird beetle Coccinella septempunctata

Ist Teil von

• Nature communications, 2013-04, Vol.4 (1), p.1661-1661, Article 1661

Ort / Verlag

London: Nature Publishing Group UK

Erscheinungsjahr

2013

Quelle

Electronic Journals Library

Beschreibungen/Notizen

• For an insect to be able to efficiently attach to surfaces, the adhesive pads on the distal parts of its legs must establish large contact areas. In case of hairy adhesive pads this requires flexibility of the contact-forming bristles, called adhesive tarsal setae. However, too flexible setae would have a low mechanical stability resulting in a decreased attachment ability of the pads. Here we show that the adhesive tarsal setae of the ladybird beetle Coccinella septempunctata feature pronounced gradients in the material composition and properties along their length. The Young’s modulus ranges from 1.2 MPa at the tips, where we found the incorporation of high proportions of the elastic protein resilin, to 6.8 GPa at the bases of the setae. These gradients likely represent an evolutionary optimization, which increases the performance of the adhesive system by enabling effective adaptation to rough surfaces while simultaneously preventing lateral collapse of the setae. Many insects cling to surfaces by means of specific bristles on the tips of their legs. Peisker et al. show that in the beetle Coccinella septempunctata the composition and stiffness of these bristles vary dramatically along their length, likely allowing for a better grip to uneven surfaces.