Fig. 4: Schematic representation of AFM experiment and adhesion force of footprints.

A The footprint of cyprid left on the NH₂-coated surface was first imaged by AFM, and then the nano-mechanical properties were studied. The typical force curves of footprints from cyprids treated with Ado (B) and control (C). The gray curves represent the approach and the pink lines are the retraction curves. The maximum force magnitude during withdrawal with respect to the zero-force baseline is defined as the adhesion force. D Violin plot showing a significant increase in the adhesion force of footprints after Ado treatment (n = 57), compared to the control group (n = 52) (p < 0.001 by independent samples t test). The lines in the box represent the medians; box limits indicate the 25th and 75th percentiles; whiskers extend 1.5 times the interquartile range from the 25th and 75th percentiles; polygons represent density estimates of data and extend to extreme values.