J4 ›› 2016, Vol. 13 ›› Issue (3): 373-387.doi: 10.1016/S1672-6529(16)60310-4
Slippery Surface of Nepenthes alata Pitcher: The Role of Lunate Cell and Wax Crystal in Restricting Attachment Ability of Ant Camponotus japonicus Mayr
Lixin Wang1, Shiyun Dong2 Qiang Zhou3
- 1. College of Mechanical Engineering, Hebei University of Science and Technology, Shijiazhuang 050018, China
2. National Key Laboratory for Remanufacturing, Academy of Armord Forces Engineering, Beijing 100072, China
3. Department of Mechatronic Engineering, China Agricultural University, Beijing 100083, China
Slippery Surface of Nepenthes alata Pitcher: The Role of Lunate Cell and Wax Crystal in Restricting Attachment Ability of Ant Camponotus japonicus Mayr
Lixin Wang1, Shiyun Dong2 Qiang Zhou3
- 1. College of Mechanical Engineering, Hebei University of Science and Technology, Shijiazhuang 050018, China
2. National Key Laboratory for Remanufacturing, Academy of Armord Forces Engineering, Beijing 100072, China
3. Department of Mechatronic Engineering, China Agricultural University, Beijing 100083, China
摘要：
This study attempts to investigate how the slippery surface of Nepenthes alata pitchers restricts the attachment ability of ant Camponotus japonicus Mayr, via climbing behavior observation and friction force measurement. Ants exhibited ineffective climbing behaviors and rather small friction forces when attached to upward-oriented slippery surfaces, but opposite phenomena were shown when on inverted surfaces. Friction forces of intact, claw tip-removed and pad-destroyed ants were measured on intact and de-waxed slippery surfaces, exploring the roles of wax crystals and lunate cells in restricting ant’s attachment. On downward-directed slippery surfaces, greater forces were exhibited by intact and pad-destroyed ants; on the two slippery sur-faces, pad-destroyed ants presented slightly smaller forces and clawless ants generated considerably smaller forces. Somewhat different force was provided by clawless ants on upward and downward oriented slippery surfaces, and slightly higher force was shown when ants climbed on wax-removed surface. Results indicate that the lunate cells contribute greatly to decrease the friction force, whereas the wax crystals perform a supplementary role. Mechanical analysis suggests that the directionally growing lunate cells possess a sloped structure that effectively prevents the claw’s mechanical interlock, reducing the ant’s attachment ability considerably. Our conclusion supports a further interpretation of slippery surface’s anti-attachment mecha-nism, also provides theoretical reference to develop biomimetic slippery plate to trap agricultural insect.